COMPARATIVE SURVIVAL STUDY (CSS) of PIT
Transcription
COMPARATIVE SURVIVAL STUDY (CSS) of PIT
COMPARATIVE SURVIVAL STUDY (CSS) of PIT-tagged Spring/Summer Chinook and Summer Steelhead 2010 Annual Report BPA Contract #19960200 Prepared by Comparative Survival Study Oversight Committee and Fish Passage Center: Jack Tuomikoski, Jerry McCann, and Thomas Berggren, Fish Passage Center Howard Schaller, Paul Wilson, and Steve Haeseker, U.S. Fish and Wildlife Service Jeff Fryer, Columbia River Intertribal Fish Commission Charlie Petrosky, Idaho Department of Fish and Game Eric Tinus and Tim Dalton, Oregon Department of Fish and Wildlife Robin Ehlke, Washington Department of Fish and Wildlife Project Leader: Michele DeHart, Fish Passage Center 1 DRAFT 08/31/2010 2 Table of Contents Chapter 1 Introduction ............................................................ 6 Development of the Comparative Survival Study Data generated in the Comparative Survival Study Overview of Bootstrapping Estimation Approach CSS PIT tagging operations Coordination and pre-assignments during 2010 Snake River hatchery Sockeye Historic in-river conditions and transportation 10 12 15 15 16 19 20 Chapter 2 Annual metrics of juvenile survival, arrival time, and migration rate .................................................................. 22 Methods PIT-tagged fish and the annual estimates Results Annual summaries of out-migration timing, migration rates, and reach survivals Annual out-migration timing (Snake River basin groups) Annual out-migration timing (Snake River and Columbia River basin groups) Annual out-migration timing (Snake River hatchery sockeye) Annual fish migration rate (Snake River basin groups) Annual fish migration rate (Snake River and Columbia River basin Groups) Annual fish migration rate (Snake River hatchery sockeye) Annual survival (Snake River basin groups) Annual survival (Snake River and Columbia River basin groups) Annual survival (Snake River and hatchery sockeye) Discussion 22 22 23 23 23 28 34 35 36 39 40 47 49 50 Chapter 3 Effects of the in-river environment on juvenile travel time, instantaneous mortality rates and survival...... 51 Methods Study area and definitions Multiple regression modeling Fish travel time Survival Instantaneous mortality rates Environmental variables Variable selection and model building Survival modeling approach Results Discussion 51 51 52 52 53 53 54 55 56 56 65 Chapter 4 Annual SAR by Study Category, TIR, and D for Snake River Hatchery and Wild Spring/Summer Chinook Salmon and Steelhead: Patterns and Significance.............. 66 Methods 67 3 Estimation of smolt numbers in study categories Pre-2006 migration years Migration years 2006 and later Estimation of SARs and Ratios of SARs for Study Categories Estimation of D Results Estimates of SAR by Study Category Wild and hatchery Chinook Wild and hatchery Steelhead Estimates of TIR and D Wild and hatchery Chinook Wild and hatchery steelhead Discussion 67 67 70 72 74 76 76 76 81 84 84 90 93 Chapter 5 Adult passage success rates between dams, D, and the expression of delayed effects. ................................... 95 Introduction Methods Adult passage success by migration year Modeling success rates vs. smolt outmigration experience and return year conditions Observations of straying and straying rates Results Adult passage success by migration year Partitioning D Modeling success rates vs. smolt outmigration experience and return year conditions Observations of straying and straying rates Discussion Supporting tables 95 96 96 97 99 99 99 100 104 104 109 111 Chapter 6 Patterns in Annual Overall SARs .................... 117 Methods 119 Estimation of 90% confidence intervals for annual SARs applicable to all mark populations 119 Snake River basin populations originating above Lower Granite Dam 120 Estimation of overall annual SARs for pre-2006 smolt migration years 120 Estimation of overall annual SARs in smolt migration year beginning 2006 121 Middle and Upper Columbia River basin populations 121 Estimation of overall annual SARs in all smolt migration years 121 Results 122 Snake River Overall SARs 122 Mid Columbia River Overall SARs 126 Upper Columbia River Overall SARs 129 Comparison of PIT-tag and Run Reconstruction SARs 129 First Year Ocean Survival Rate (S.o1) 133 Discussion 133 Supporting Tables 136 4 Chapter 7 Effects of Bypass Systems on Juvenile Travel Times and SARs .................................................................... 147 Introduction Effects of bypass systems on juvenile fish travel time Methods Results Discussion Effects of bypass systems on post-Bonneville Dam survival Methods Results Discussion Meta- Analysis comparing SARs of C1 and C0 wild Chinook and steelhead Methods Results Discussion 147 148 148 149 150 153 153 155 160 160 161 162 165 References.............................................................................. 167 Appendix A Source of PIT-tagged Fish ............................. 175 PIT-tagged Wild Chinook Aggregate – Composition by Drainage PIT-tagged Rapid River Hatchery Spring Chinook – Salmon River Drainage PIT-tagged Dworshak Hatchery Spring Chinook – Clearwater River Drainage PIT-tagged McCall Hatchery Summer Chinook – Salmon River Drainage PIT-tagged Imnaha Hatchery Summer Chinook – Imnaha River Drainage PIT-tagged Catherine Creek AP Spring Chinook – Grande Ronde River Drainage PIT-tagged Hatchery Chinook Additions to CSS PIT-tagged Wild Steelhead Aggregate – Composition by Drainage PIT-tagged Hatchery Steelhead Aggregate – Composition by Drainage PIT-tagged Hatchery Steelhead by Drainage and Run-type for 2008 PIT-tagged Hatchery Steelhead by Drainage and Run-type for 2009 175 175 176 176 177 177 177 178 178 179 179 Appendix B Dam-specific Transportation SARs .............. 180 Appendix C Estimate proportion of smolts experiencing TX, C0, and C1 passage routes..................................................... 184 Methods Results 184 185 5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Chapter 1 Introduction The Comparative Survival Study (CSS; BPA Project 199602000) began in 1996 with the objective of establishing a long term dataset of the survival rate of annual generations of salmon from their outmigration as smolts to their return to freshwater as adults to spawn (smolt-to-adult return rate; SAR). The study was implemented with the express need to address the question of whether collecting juvenile fish at dams, transporting them downstream of Bonneville Dam (BON) and then releasing them was compensating for the effect of the Federal Columbia River Power System (FCRPS) on the survival of Snake Basin spring/summer Chinook salmon which migrate through the hydrosystem. The CSS is a long term study within the Northwest Power and Conservation Council’s Columbia Basin Fish and Wildlife Program (NPCC FWP) and is funded by Bonneville Power Administration (BPA). Study design and analyses are conducted through a CSS Oversight Committee with representation from Columbia River Inter-Tribal Fish Commission (CRITFC), Idaho Department of Fish and Game (IDFG), Oregon Department of Fish and Wildlife (ODFW), U.S. Fish and Wildlife Service (USFWS), and Washington Department of Fish and Wildlife (WDFW). The Fish Passage Center (FPC) coordinates the PIT-tagging efforts, data management and preparation, and CSSOC work. All draft and final written work products are subject to regional technical and public review and are available electronically on FPC and BPA websites: FPC: http://www.fpc.org/documents/CSS.html and BPA: http://www.efw.bpa.gov/searchpublications/index.aspx?projid The completion of this annual report for the CSS signifies the 14th outmigration year of hatchery spring/summer Chinook salmon marked with Passive Integrated Transponder (PIT) tags as part of the CSS. Its’ also the 11th complete brood year return as adults of those PIT-tagged fish, covering adult returns from 1997-2008 hatchery Chinook juvenile migrations. In addition, the CSS has provided PIT-tags to on-going tagging operations for wild Chinook since 2002 (report covering adult returns from 1994-2008 wild Chinook juvenile migrations). The CSS tagged wild steelhead on the lower Clearwater River and utilized wild and hatchery steelhead from other tagging operations in evaluations of transportation, covering adult returns from 19972006 wild and hatchery steelhead migrations. The primary purpose of this report is to update the time series of smolt-to-adult survival rate data and related parameters with additional years of data since the completion of the CSS 10-yr retrospective analysis report (Schaller et al 2007). The 10-yr report provided a synthesis of the results from this ongoing study, the analytical approaches employed, and the evolving improvements incorporated into the study as reported in CSS annual progress reports. This current report specifically addresses the constructive comments of the most recent regional technical review conducted by the Independent Scientific Advisory Board and Independent Scientific Review Panel (ISAB and ISRP 2007) and the comments on the CSS study found in (ISAB 2010). This report completes the 3-salt returns from migration year 2006 for wild and hatchery Chinook and steelhead (all returns are to Lower Granite Dam). For wild and hatchery Chinook, this report also provides 3-salt returns from migration year 2007 and 2-salt returns from migration year 2008 through a cutoff date of 28 May 2010. For wild and hatchery 6 1 2 3 4 5 6 7 8 9 10 11 12 13 steelhead, it provides completed 2-salt returns for wild and hatchery steelhead that outmigrated in 2007 (any 3-salt returns of PIT-tagged steelhead are few, but will occur after July 1, 2010). All of the Chinook salmon evaluated in the CSS study exhibit a stream-type life history. All study fish used in this report were uniquely identifiable based on a PIT-tag implanted in the body cavity during (or before) the smolt life stage and retained through their return as adults. These tagged fish can then be detected as juveniles and adults at several locations of the Snake and Columbia rivers. Reductions in the number of individuals detected as the tagged fish grow older provide estimates of survival. This allows comparisons of survival over different life stages between fish with different experiences in the hydrosystem (e.g. transportation vs. in-river migrants and migration through various numbers of dams) as illustrated in Figure 1.1. The location of all tagging sites is identified in Figures 1.2 and 1.3. Freshwater Hatchery Smolts/ spawner Harvest Management Wild 14 15 16 17 18 19 Eggs S/S Lower Granite Little Goose Lower Monumental SAR & TIR Ice Harbor McNary John Day Direct survival through dams The Dalles Bonneville R/S Mainstem Direct survival of transported fish Estuary D Spawning / Rearing Habitat Actions Ocean Hydrosystem Actions Estuary Habitat Actions Figure 1.1. Salmonid life cycle in the Snake River and lower Columbia River basins (Source: Marmorek et al. 2004). . The adults metrics found in this report will be updated in September of 2010 while the draft is being reviewed and the report will be updated with these metrics in its final version. 7 1 2 3 Figure 1.2. CSS PIT tag release locations and PIT-tag detection sites in the Columbia River Basin. 8 1 2 Figure 1.3. CSS PIT-tag release watersheds and PIT-tag detection sites in the Columbia River Basin. 9 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Throughout this report we organized groups of stocks primarily according to DPS/ESU boundaries (e.g., Snake River, Mid Columbia River, Upper Columbia River). However, we add the caveat that we have presented Snake River stocks only above Lower Granite Dam; also, Carson National Fish Hatchery is actually located within the Lower Columbia Chinook ESU but we present it here as a Mid Columbia group. This was for simplification as this was the only Lower Columbia group presented, but also because its lineage is from upriver stocks and its location is upstream of Bonneville Dam. Development of the Comparative Survival Study Beginning in 1981, collection of fish at lower Snake River dams and transportation to below Bonneville dam was institutionalized as an operational program by the U.S. Army Corps of Engineers (USACE). The intention was to mitigate for mortality impacts associated with the FCRPS, and thus to increase survival of spring/summer Chinook salmon. However, abundance of Snake River spring/summer Chinook salmon continued to decline. Fisheries that had been conducted at moderate levels in the Columbia River main stem during the 1950s and 1960s were all but closed by the mid 1970s. In 1992, the Snake River spring/summer Chinook salmon Evolutionarily Significant Unit (ESU) was listed under the federal Endangered Species Act (ESA). Spawning ground survey results in the mid-1990s indicated virtually complete brood year failure for some wild populations. For hatchery fish, low abundance was a concern as the Lower Snake River Compensation Plan (LSRCP) hatcheries began to collect program brood stock and produce juveniles. The motivation for the CSS began with the region’s fishery managers expressing concern that the benefits of transportation were less than anticipated (Olney et al. 1992, Mundy et al. 1994, and Ward et al. 1997). Experiments conducted by the National Marine Fisheries Service (NMFS) prior to the mid-1990s sought to assess whether transportation increased survival beyond that of smolts that migrated in-river through the dams and impoundments. Regional opinions concerning the efficacy of transportation ranged from transportation being the best option to mitigate for the impacts of the FCRPS, to the survival of transported fish was insufficient to overcome those FCRPS impacts. Although the survival of fish transported around the FCRPS could be demonstrated to be generally higher than the survival of juveniles that migrated in the river, evidence on whether transportation contributed to significant increases in adult abundance of wild populations was unavailable. If the overall survival rate (egg to spawner) was insufficient for populations to at least persist, the issue would be moot (Mundy et al. 1994). The objectives of the CSS design translate these issues about the efficacy of transportation into key response variables. The CSS uses the following two aspects for evaluating the efficacy of transportation: 1) empirical SARs compared to those needed for survival and recovery of the ESU; and 2) SAR comparisons between transport and inriver migration routes. In this broader context, the primary objective is to answer: “Are the direct and delayed impacts of the configuration and operation of the FCRPS sufficiently low to ensure that cumulative life-cycle survival is high enough to recover threatened and endangered populations?” Therefore we measure SARs against the 10 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 regional management goal to maintain SARs between 2-6%, where 2% is a minimum requirement and an average of 4% is maintained over multiple generations (NPCC 2009). The secondary objective is to answer: “is the survival of transported fish (SAR) higher than the survival (SAR) of fish migrating in-river?” Combining these objectives, effectiveness of transportation is assessed by whether 1) the survival (SAR) of fish collected at Snake River dams and diverted into barges is higher than the SAR of fish that migrate through reservoirs and pass these dams via the spillways and turbines; and 2) the SAR meets the regional objective (2-6%) for the ESU. The design and implementation of the CSS improved upon shortcomings of the methods that had previously been used to estimate and compare survival rates for transported fish and non-transported (in-river migrating) fish. These shortcomings resulted from the collection and handling protocols, the marking and recovery technology, the study objectives, the definition and use of a control population, and the inconsistency and duration of survival studies (Olney et al. 1992, Mundy et al. 1994, and Ward et al.1997). Transported and in-river fish groups were handled differently in the first juvenile fish studies. Whereas transported fish were captured at dams, tagged, and placed in trucks or barges, some in-river control groups of fish were transported back upstream for release. Thus, unlike the unmarked outmigration run-at-large, these marked in-river fish were therefore subjected to the same hydrosystem impacts multiple times whether they were subsequently collected and transported or remained in-river. The early mark-recapture studies used coded-wire tags (CWT) and freeze brands to mark juveniles collected at the dams. Therefore, Snake River basin origin of individual fish could not be identified, and CWT information could be obtained only from sacrificed fish. Evidence suggested that the process of guiding and collecting fish for either transport or bypass contributed to juvenile fish mortality and was cumulative when fish were bypassed multiple times. If such mortality differentially impacted the study fish, and was not representative of the in-river migrant run-at-large, measures of the efficacy of transportation would be biased. All CSS study fish are uniquely identified with a PIT-tag, and the use of this technology has provided substantial improvements in the evaluation of the efficacy of transportation. To ensure that all CSS study fish, whether transported or migrating inriver, experience the same effects from handling (thus improving the utility of an in-river control group relative to transportation), fish are tagged at hatcheries and wild fish are tagged at subbasin and main stem outmigrant traps upstream of the FCRPS (Figures 1.2 and 1.3). PIT-tagged juveniles are released near their marking station, allowing the numbers of fish and distribution across subbasins of origin to be predetermined. Recapture information can be collected without sacrificing each fish, and lower impacts due to trapping and handling occur where automated detection stations exist. The Columbia and Snake River mainstem PIT-tag detectors at the dams now allow passage dates and locations to be recorded for both juvenile and adult PIT-tagged fish and provide the ability to link that information to the characteristics of each fish at time and location of release (Figures 1.2 and 1.3). Given sufficient numbers of fish among release groups and appropriate distribution across subbasins, ESUs, hatchery vs. wild, and outmigration season, survival rates of subgroups of fish with unique life history experience, or aggregate groups with common life history experiences, can be estimated at discrete or combined life-stages throughout their life cycle. The CSS PIT-tagging 11 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 design and application allows the use of the Cormack-Jolly-Seber (CJS; see Chapter 2) method with multiple mark-recapture information to estimate survival of the total number of fish estimated to approach the upper most dam (Lower Granite Dam), thus representing the conditions that the majority of fish migrating through the hydrosystem experience. Data generated in the Comparative Survival Study The Comparative Survival Rate Study (CSS) is a management-oriented, large scale monitoring study of spring/summer Chinook and steelhead. The CSS was designed to address several of the basin-wide monitoring needs and to provide demographic and other data for Snake River and Columbia River wild and hatchery salmon and steelhead populations. One product of the CSS is annual estimates of SARs for Snake River hatchery and wild spring/summer Chinook and steelhead. Estimation of the overall, aggregate SARs of fish that are transported and those that migrate entirely in-river is key to evaluation of avoidance of jeopardy (i.e., put at risk of extinction) as well as progress towards recovery goals. Monitoring survival rates over the entire life-cycle can help identify where survival bottlenecks are occurring, which is critical input for informed management decisions (Good et al. 2007). The CSS is also examines environmental factors associated with life-cycle survival rates and evaluates the hypothesized mechanisms for variations in those rates. Generally we estimated the survival of various life stages through known release and detected return numbers of PIT-tagged fish. The PIT-tags in juvenile fish are read as the fish pass through the coils of detectors installed in the collection/bypass channels at six Snake and Columbia River dams, including LGR (Lower Granite), LGS (Little Goose), LMN (Lower Monumental), MCN (McNary), JDA (John Day), and BON (Bonneville) (Figures 1.2 and 1.3). Upon arrival at LGR, LGS and LMN, smolts can travel through three different routes of passage: over the spillway via typical spillway or removable spillway weir (RSW), or into the powerhouse and subsequently through the turbines, or diversion with screens and pipes into the collection and bypass facility. Those smolts that pass over the spillway or through the turbines are not detected, but the bypass facility does detect and record the fish identification number and the time and date detected. During transportation operations, smolts without PIT-tags that enter the collection facility are generally put in trucks or barges and transported to below BON. Prior to 2006, groups of PIT tagged fish were assigned an “action code" that determined their route in the bypass facility (e.g. in-river or transport). Starting in 2006, researchers submitted groups of PIT tagged fish that would then follow the same route as un-tagged fish or, if not submitted, would follow the default return to river route. In addition, PITtag detections are obtained from a special trawling operation (TWX) by NMFS in the lower Columbia River in the vicinity of Jones Beach. Returning adults with PIT-tags are detected in the fish ladders at LGR with nearly 100% probability. PIT-tag detection capability for returning adults has been added at BON, MCN, and IHR in recent years allowing for additional analyses. A specific goal of the CSS has been to develop long-term indices of SAR ratios between transported and in-river fish. A common comparison, termed “Transport: Inriver” ratio, or TIR, is the SAR of transported fish divided by the SAR of in-river fish, 12 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 with SAR being estimated for smolts passing LGR and returning as adults back to the adult detector at LGR (GRA). Additionally, SARs from LGR to the adult detector at Bonneville (BOA) are provided. Estimates of TIR address the question of whether transportation provides an overall benefit to smolt-to-adult survival, compared to leaving smolts to migrate in-river, under the hydrosystem as currently configured. The overall value of transportation in avoiding jeopardy and promoting recovery depends on the extent to which it circumvents direct mortality (i.e., to smolts within the hydrosystem) and indirect, or “delayed”, mortality (i.e., to smolts after passing BON) caused as a result of passage through the hydrosystem. However, because TIR compares SARs starting from collector projects, it does not by itself provide a direct estimate of any delayed mortality specific to transported fish. Related to TIR is “D”, the ratio between SARs of transported fish and in-river fish from downstream of Bonneville Dam (BON) as smolts back to LGR as adults (BON-toGRA SARs). Estimates of D isolates mortality occurring during juvenile salmon passage between Lower Granite and Bonneville dams from mortality occurring afterwards (during time in the ocean and upon returning upriver as adults to Lower Granite Dam for transported smolts). When D is equal to one it indicates that there is no difference in the survival rate of transported or in-river fish after hydrosystem passage. When D is less than one (D < 1), it indicates that transported smolts die at a higher rate after passing BON compared to in-river smolts (which have migrated through the hydrosystem). If D is greater than one (D > 1), it indicates transported fish have higher survival after passing BON compared to in-river fish. D has been used extensively in modeling the effects of the hydrosystem on Snake River Chinook salmon (Kareiva et al. 2000; Peters and Marmorek 2001; Wilson 2003; Zabel et al. 2008). Estimation and comparison of annual SARs for hatchery and wild groups of smolts with different hydrosystem experiences between common start and end points are made for three categories of fish passage: 1. tagged fish that are detected at Snake River collector dams (LGR, LGS or LMN) and transported; 2. tagged fish collected at Snake River dams and returned to the river (C1), or 3. tagged fish never collected or transported at the Snake River dams (C0). The year 2006 marked an important change in fish transportation operations within the FCRPS. Transportation operations from 1997-2005 began ~ April 1st and encompassed most of the emigrating groups of CSS marked fish. In 2006, the transportation operational protocol was altered at the three Snake River collector dams. The start of transportation was delayed at LGR until April 20 in 2006 and until May 1 from 2007 through 2009. The start of transportation at LGS and LMN was delayed further to account for smolt travel time between projects, ranging from 4 to 12 days later than LGR depending on year. This change in operations affects the CSS study because the transportation protocol now allows a portion of the population to migrate entirely inriver through the hydrosystem before transportation begins. This 2006 management change coincided with the CSS change in methods that pre-assigns fish to bypass or transport routes, rather than forming transport and in-river cohorts at Snake River collector projects as was done through 2005. The new CSS approach facilitated evaluation of the 2006 change in transportation strategy. Prior to 2006, the electronics at the dams were used to route fish during the out-migration either 13 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 to raceways or back-to-river. The new method pre-assigns the tagged fish to two different study groups prior to their emigration through the hydrosystem. This is accomplished through FPC coordination with various marking agencies. By knowing what PIT tags are used for marking, FPC assigns individual PIT tags to two groups, and passes this information on to the separation-by-code facilities at each dam. One group (denoted as Group T in this report) reflects the untagged population, and these tagged fish are routed in Monitor-Mode in order to go the same direction as the untagged smolts at each of the collector dams where transportation occurs. The other group (denoted as Group R in this report) follows the default return-to-river routing at each collector dam throughout the season. For example, on entering the bypass facilities at the transportation sites two things can happen. If transportation is taking place, Group T fish are transported and Group R fish are bypassed. If transportation is not taking place, both groups are bypassed. Smolts in the two study groups created would experience different passage routes through the hydrosystem whenever transportation was occurring. In the future, these two groups will provide the opportunity to compare estimated SARs between transport and non-transportation management scenarios. The transport category of fish passage, category 1 above, is termed T0 (i.e. a first time detected and transported smolt from a collector dam) in years prior to the transportation delay and TX (i.e. a transported smolt from a collector dam with or without an upstream detection) in years with a delay. These SARs and the ratios derived from them in this report are estimated for the entire migration year. For years prior to 2006, the SARs developed for each of these study categories are weighted by the proportion of the run-at-large (untagged and tagged fish) represented by these categories to provide overall annual SARs. A more direct estimation of overall annual SARs is possible beginning in 2006 with the pre-assignment of PIT-tagged study fish prior to release into a monitor-mode group (Group T) which passed through the collector dams in the same manner as untagged smolts. Because no transported smolts and only a small number of in-river smolts are enumerated at BON, the BON-to-GRA SAR is estimated from the LGR-to-GRA SAR, adjusted by annual in-river survival rate estimates (through the hydrosystem) and assumed average direct transport survival rate from empirical studies. Combining Groups T and R provides a composite group (Group CRT) comparable to what has been used in the CSS in all migration years through 2005. For the analyses work in this report, we use Group CRT to estimate CJS reach survival rates and detection probabilities. These CJS reach survival rate and collection probability parameter estimates are then used to generate key parameters for both the component groups T and R. The estimation of TIRs and D will have TX replace T0 smolts in migration years after 2005, while C0 smolts are estimated the same in all years. The estimated smolt numbers and adult return data for Group T provides a direct estimation of the annual overall SARs beginning with the 2006 migrants. To evaluate different aspects of the effectiveness of transportation relative to in-river migration, annual SAR ratios between T0 (or TX) and C0 fish are compared, first from passage at LGR as smolts to their return as adults to LGR (TIR). This represents the direct effects of transportation versus in-river migration on survival in the freshwater migration corridor as well as the indirect effects (i.e. delayed effects) in the estuary, ocean, and during the adult escapement to LGR. The second comparison is with D which 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 represents only the delayed differential survival effects in the estuary, ocean, and during the adult upstream migration between transported and in-river juvenile outmigrants. Overview of Bootstrapping Estimation Approach Over the years, we have developed a computer program to estimate the following quantities with confidence intervals: survival from hatchery release to LGR; reach survival estimates between each of the dams equipped with PIT-tag detectors; survival from smolt arrival at LGR dam until return to LGR as adults (LGR-to-GRA SAR); survival from smolt outbound arrival at BON to LGR as adults (BON-to-GRA SAR); and the ratio of these SARs for smolts with different hydrosystem passage experience (TIR and D). Assessment of the variance of estimates of survival rates and ratios is necessary to describe the precision of these estimates for statistical inference and to help monitor actions to mitigate effects of the hydrosystem. For a number of the quantities described above, theoretical estimates of variance are tractable. However, variance components of other quantities are often unknown or are extremely complicated and thus impracticable to estimate using theoretical variances. Therefore, we developed a nonparametric bootstrapping approach (Efron and Tibshirani 1993), where first the point estimates are calculated from the population, then the data is re-sampled with replacement to create 1000 simulated populations. These 1000 iterations are used to produce a distribution of values that describe the mean and variance associated with the point estimate. From the set of 1000 iterations, non-parametric 80%, 90%, and 95% confidence intervals were computed for each parameter of interest. The 90% confidence intervals were chosen for reporting in the recent CSS annual reports in an attempt to better balance the making of Type I (failure to reject a false null hypothesis) and Type II (failure to accept a true alternative hypothesis) errors in comparisons among study groups of fish for the various parameters of interest. CSS PIT tagging operations Wild and hatchery smolts are marked with glass-encapsulated, passively induced transponders that are 11-12 mm in length and have a unique code to identify individual fish. These PIT-tags are normally implanted into the fish’s body cavity using a hand-held syringe, and they are generally retained and function throughout the life of the fish. Snake River basin wild and hatchery Chinook and steelhead used in the CSS analyses were obtained from all available marking efforts above LGR. Wild Chinook from each tributary (plus fish tagged at the Snake River trap near Lewiston) were represented in the PIT-tag aggregates for migration years 1994 to 2009. The sample sizes for each group with tags provided by the CSS from 1994-2009 are presented in Appendix A. Additionally, during 2010 tagging operations began in cooperation with the Washington Department of Fish and Wildlife on wild Chinook and steelhead in the Upper Columbia basin and are ongoing at the time of this report. Snake River hatchery yearling spring and summer Chinook were PIT-tagged for the CSS at specific hatcheries within the four drainages above LGR including the Clearwater, Salmon, Imnaha, and Grande Ronde Rivers. Hatcheries that accounted for a major portion of Chinook production in their respective drainages were selected. Since 15 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 study inception in 1997, the CSS has PIT-tagged juvenile Chinook at Rapid River, Dworshak, McCall and Lookingglass hatcheries. Two Chinook stocks are tagged for the CSS at Lookingglass Hatchery: an Imnaha River stock released into the Imnaha River and a Catherine Creek stock released in the Grand Ronde River drainage. This latter stock became available to the CSS in 2001 after the Lookingglass Hatchery complex changed its operation to rearing only Grande Ronde River basin endemic stocks. Beginning in 2009, the CSS is also contributing PIT tags to additional LSCRP hatcheries including spring Chinook from Clearwater Hatchery in the Clearwater River basin and summer Chinook from Pahsimeroi Hatchery and spring Chinook from Sawtooth Hatchery in the Salmon River basin. Wild steelhead smolts from each tributary (plus fish tagged at the Snake River trap near Lewiston) were represented in the PIT-tag aggregates for migration years 1997 to 2009. Hatchery steelhead from each tributary, plus PIT-tag releases in the mainstem Snake River at the Lewiston trap and below Hells Canon Dam, were represented in the PIT-tag aggregates for migration years 1997 to 2007 with more extensive PIT tagging of hatchery steelhead beginning in 2008. This increased again in 2009 with the addition of the Niagara Spring Hatchery production. In coming years with the greater coverage of hatchery steelhead above LGR, separation of metrics into A and B runs and by basin should be possible. Based on past estimates of SARs, sufficient numbers of smolts were tagged to ensure enough returning adults to compute statistically rigorous SAR estimates. Required samples sizes for SAR estimates are discussed in Appendix B of the CSS 2008 annual report. All attempts were made to ensure that the PIT-tagged fish are representative of their untagged cohorts. The origins of the wild Chinook, wild steelhead, and hatchery steelhead in the PIT-tag aggregates appear to be well spread across the drainages above LGR (Appendix A). At trapping sites, sampling and tagging occur over the entire migration season. At the hatcheries, fish were obtained across a wide set of ponds and raceways to most accurately represent production. Pre-release tag loss and mortality of PIT-tagged fish were monitored, and the tagging files were transferred to the regional PTAGIS database in Portland, OR. The study requires that prior to preassigning groups, PIT-tagged fish are not necessarily routed or diverted at collector projects in the proportions that non-tagged fish are; consequently adjustments are made (described in Chapter 4) in estimation to more closely represent the experience of run-ofthe-river (non-tagged) fish. Coordination and pre-assignments during 2010 Marked fish utilized in the CSS may be from groups PIT tagged specifically for this program or may be from marked groups planned for other research studies. Wherever possible the CSS makes use of mark groups from other research and coordinates with other marking programs to meet CSS requirements in order to reduce costs and handling of fish. To that end, the CSS has a history of collaboration and is currently cooperating with several other agencies in the marking and pre-assignment of smolts. All of the smolts marked and pre-assigned during the 2010 migration year are outlined in Tables 1.1-1.3 (these releases will be analyzed in future reports). 16 1 2 3 4 5 6 7 8 The CSS will continue coordination efforts to affect cost savings and avoid redundancy as recommended by the ISAB/ISRP reviews (2007 and 2009). Collaboration on Snake River basin hatchery fish in recent years includes those with the marking programs of the Lower Snake River Compensation Plan. Specifically this includes Idaho Fish and Game, Oregon Department of Fish and Wildlife, and Washington Department of Fish and Wildlife (Table 1.1). Additionally, the CSS has collaborated with Idaho Power Company (IPC) and the U.S. Fish and Wildlife Service (USFWS). Table 1.1. Snake River hatchery groups marked during 2010 that have all or part of their PIT tags provided by the CSS. Many groups have tags cooperatively provided the CSS and other entities. The hatchery, species, tag funding sources and tag totals are shown for each. Through cooperative efforts pre-assignments are carried out by either the CSS or the other associated agencies. 9 PIT Tag Funding Source Hatchery Rapid River McCall's Clearwater Pahsimeroi Sawtooth Magic Valley Hagerman Niagara Springs Clearwater Lookingglass (Imnaha AP) Lookingglass (Catherine AP) Species Chinook Chinook Chinook Chinook Chinook Steelhead Steelhead Steelhead Steelhead 20,000 51,000 15,000 24,600 19,000 16,800 ODFW / WDFW / CSS IPC LSRCP USFWS LSRCP Total PIT tags 32,000 20,000 52,000 32,000 52,000 21,800 72,800 6,400 15,000 21,400 6,400 21,400 10,400 35,000 8,100 27,100 22,300 6,000 28,300 7,000 23,800 Chinook 21,000 21,000 Chinook 21,000 21,000 Irrigon (Grande Ronde, Steelhead Imnaha) Dworshak Chinook Dworshak Steelhead Lyon's Ferry Steelhead (Cottonwood AP) Grand Total IDFG / LSRCP 14,000 31,400 52,000 9,000 14,000 19,900 2,000 146,400 265,400 41,000 31,400 52,000 9,000 6,000 19,900 6,000 2,000 452,800 Agencies are Idaho Fish and Game (IDFG), Idaho Power Company (IPC), Oregon Department of Fish and Wildlife (ODFW), U.S. Fish and Wildlife Service (USFWS), Washington Department of Fish and Wildlife (WDFW), and Lower Snake River Compensation Plan (LSRCP) 10 11 12 13 14 15 Coordination and cooperation has been part of the marking efforts on wild fish throughout the history of the CSS. The CSS has coordinated with the Smolt Monitoring Project (SMP) over several years of both studies. During the 2010 marking, a new study group has been added to the CSS through collaboration with Washington Department of Fish a Wildlife; wild steelhead and Chinook marked in the upper Columbia are now 17 1 2 3 included in the study (Table 1.2). Metrics and analyses on these groups will be presented in future CSS reports. Table 1.2. Wild fish marked in 2010 that have all or part of their PIT tags provided by the CSS. Many groups have tags cooperatively provided the CSS and other studies. The location of marking, species, tag funding sources and tag totals are shown for each. Through cooperative efforts preassignments are carried out by the CSS on these groups except for the Chiwawa Trap and Lower Wenatchee Trap (i.e. Upper Columbia Basin). PIT Tag Funding Source Location Wild Species SMP CSS IDFG ODFW Total PIT tags Clearwater/Salmon tributaries Ch./St. 24,000 40,000 64,000 Snake & Salmon Traps Ch./St. 23,400 7,000 30,400 Clearwater Trap Ch./St. 5,200 5,200 Grande Ronde Trap Ch. 9,000 1,400 10,400 Grande Ronde tributaries Ch. 2,200 2,500 4,700 Chiwawa Trap, Lower Wenatchee Trap Ch./St. 30,000 30,000 32,400 69,800 40,000 2,500 Grand Total 144,700 Agencies are Smolt Monitoring Program (SMP), Idaho Fish and Game (IDFG), and Oregon Department of Fish and Wildlife (ODFW) 4 5 6 7 8 9 10 11 12 Fish to be utilized in the CSS from groups planned for other research studies during 2010 are shown in table 1.3. Two of the Snake River groups are pre-assigned by the CSS through coordination with the marking agency – the CTUIR marking in Grande Ronde basin and the SBT marking in the Salmon River basin. In the future, the CSS will continue to review on-going and planned programs in the Middle and Upper Columbia River regions, to establish stock specific or aggregate groups of marks in those regions to support CSS analysis and develop demographic survival data for those stocks. 18 1 Table 1.3. Groups marked in 2010 that do not include PIT tags provided by the CSS but are included in the study. The CSS does random pre-assignments for some groups. The location of marking/hatchery, species, primary marking agency and tag totals are shown for each. PIT Tag Marking Agency Location/Hatchery Wild Groups Lookingglass Creek (Grande Ronde basin) East Fork Salmon, West Fork Yankee Rivers (Salmon basin) Imnaha Trap (Imnaha basin) John Day River Trout Creek (Deschutes basin) Hatchery Groups Snake River Carson Cle Elum Leavenworth Warm Springs Species CTUIR SBT NPT ODFW COE USFWS YINN SMP Ch./St. 3,500* Ch./St. 1,300* Ch./St. 15,000** Ch./St. ~9,300 St. ~1,300 63,600● Sockeye Chinook Chinook Chinook Chinook Grand Total 15,000 40,000 15,000 15,000 3,500 1,300 15,000 ~10,600 63,600 30,000 40,000 15,000 * The CSS pre-assigns these groups through cooperative efforts with the primary marking agency ** Pre-assigned by NPT ● Pre-assigned by COE Agencies are: Confederated Tribes of the Umatilla Indian Reservation (CTUIR), Shoshone-Bannock Tribes (SBT), Nez Perce Tribe (NPT), Oregon Department of Fish and Wildlife (ODFW), Corps of Engineers (COE), U.S. Fish and Wildlife Service (USFWS), Yakima Indian Nation (YINN), and Smolt Monitoring Program (SMP) 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Snake River hatchery Sockeye Included in this year’s report is presentation of the juvenile metrics for the Snake River hatchery sockeye marked during 2009 at Sawtooth and Oxbow hatcheries (Chapter 3). The 2009 out-migration was the first year with a large enough sample size that would likely meet the requirements of the analytical frameworks applied in the CSS (for sample size discussion see Appendix B of the 2008 CSS report). This was in response to a request by the Shoshone-Bannock tribe to include sockeye in the CSS (Appendix D, CSS 2009 Annual Report) and should meet regional RME needs in regards to Snake River hatchery sockeye. In future reports analyses including smolt to adult survival rates for transported and in-river group comparisons should be possible. If these groups continue to be marked the CSS should be able to provide a consistent time series of smolt to adult return data and other demographic data towards the research, management and evaluation of these stocks. 19 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Historic in-river conditions and transportation The environmental conditions experienced by out-migrating juvenile yearling Chinook and steelhead have varied considerably over the historical context of the CSS (Figure 1.4). The spring spill program has been in place since 1996 though some years with low flows (2001, 2004, and 2005) had lower spill. During 2007, conditions were particularly unique with low flows accompanied by high spring spill percentages and low transportation percentages. The most recent year displayed (2009; Figure 1.4) reflects relatively high flows with high spill. Transportation protocol has varied over the years of the study as well. The transportation program underwent a change in operations during 2006. Transportation was delayed at LGR until April 20 in 2006 and until May 1 in 2007-2009; these years included a similar but lagged start date at LGS and LMN. The delayed start date was combined with an increased spill percentage from 2004 and 2005, and resulted in a lower proportion of wild smolts being transported. Smolt out-migration timing also would also affect transportation percentage and these results vary by stock (see Table 4.18 for details). The percentage of smolts transported in 2001, 2004, and 2005 were three years with the highest transportation percentages of CSS PIT-tagged wild fish. Conversely, 2007 had one of the lowest transportation percentages in recent years and much lower than other years with comparable flows. The higher spill percentage and delay of transportation contributed to a lower percentage of wild smolts transported in 2007 than other low flow years. The 2008 and 2009 migration years were very similar for wild smolts and about 40 percent of the PIT tagged Snake River wild stocks were transported. 20 1 2 3 4 5 6 7 Figure 1.4. The top, middle, and bottom panels are summaries of spill percentage, flow, and the proportion transported over the historical context of the CSS. Spill percentages and flow are shown for the three primary transportation dams. The proportion transported is shown for the wild Snake River stocks involved in the CSS as expressed by population proportion of T0 fish in migration years before 2006 (Table 7.8 and Table 7.12 in the 2009 CSS annual report). The proportion transported for migration years 2006-2009 is shown in table 4.18 of this report. 21 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Chapter 2 Annual metrics of juvenile survival, arrival time, and migration rate The CSS has established a long-term dataset of juvenile survival, arrival timing and migration rate for PIT tagged spring\summer Chinook, steelhead and sockeye from the Snake River and Columbia River basins that is in its 14th year for some groups. As a component of ongoing Research, Monitoring and Evaluation (RM&E) and Data Management studies, the data in this chapter provide quantitative information across the in-river juvenile portion of the salmon and steelhead life-cycle. This chapter presents annual juvenile metrics by hatchery and by the smallest basin possible (e.g., Snake River wild Chinook and hatchery steelhead). Here we summarize results that have been obtained to date from the CSS for annual metrics of juvenile survival, arrival time, and migration rate. The study groups in this chapter encompass three species: Chinook, steelhead, and new to this annual report, sockeye. These data include smolts from 12 different hatcheries and wild groups from the Snake River, John Day River, and Deschutes River basins. Where sample size allowed, Snake River wild Chinook and hatchery steelhead are broken up by basin (Clearwater, Imnaha, Grande Ronde, and Salmon) and, for hatchery steelhead, by stock (A and B run). Methods PIT-tagged fish and the annual estimates In this chapter, we define the hydrosystem as the overall reach between Lower Granite (LGR) Dam and Bonneville (BON) Dam. There are six dams between LGR and BON: Little Goose (LGS), Lower Monumental (LMN), Ice Harbor (IHR), McNary (MCN), John Day (JDA), and The Dalles (TDA). We divided the hydrosystem into two reaches for summarizing survival and migration rate: LGR-MCN and MCN-BON. We used PIT tag detections at LGR and BON to express juvenile out-migration timing (i.e., arrival time) for groups of marked smolts in the upper and lower hydrosystem. We define fish migration rate as the rate at which fish migrate through these reaches, expressed in kilometers per day. We used Cormack-Jolly-Seber (CJS) methods to estimate survival rates through the two reaches based on detections at the dams and in a PIT-tag trawl (TWX) operating below BON (Cormack 1964, Jolly 1965, Seber 1965, Burnham et al. 1987). The array of detection sites in the Snake and Columbia Rivers is analogous to multiple recaptures of tagged individuals, allowing for standard multiple mark-recapture survival estimates over several reaches of the hydrosystem using the Cormack-JollySeber (CJS) method. This method was used to obtain estimates of survival and corresponding standard errors for up to six reaches between release site and tailrace of BON (survival estimates S1 through S6). An overall survival probability from LGR-toBON, referred to as SR is the product of the reach survival estimates. Estimates of individual reach survival (e.g. LGR-to-LGS) can exceed 100%; however, this is often associated with an underestimate of survival in preceding or subsequent reaches. Therefore, when computing an overall multi-reach survival estimate, we allow individual 22 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 reach survival estimates to exceed 100%. However, an estimate of survival rate for a specific reach was considered unreliable when its coefficient of variation exceeded 25%. The number of inter-dam reaches for which an annual survival could be estimated was a function of the number of smolts in the each release and the recovery effort available. When fewer than six individual reach survival estimates could be made, the product of the useable estimates was extrapolated to estimate SR. Prior to 1998, there was limited PIT-tag detection capability at JDA and TWX. Reliable survival estimates in those years were possible only to the tailrace of LMN or MCN. After 1998, reliable survival estimates to the tailrace of JDA were possible in most cases. Estimation of SR with fewer than 6 individual independent estimates was calculated as follows: first, the product of the survival estimates over the longest reach possible was converted to survival per mile, then this was expanded to the number of miles between LGR and BON. However, because survival per mile rates thus generated were generally lower for the Snake River (LGR to MCN) than for the Columbia River (MCN to BON), direct estimates of in-river survival over the longest reach possible were preferable This chapter provides annual information about specific groups of juvenile fish, organized by management-oriented groups as in previous CSS reports (e.g. Dworshak hatchery Chinook, John Day River wild Chinook, etc.). We analyzed the following annual parameters and measurements: out-migration timing, LGR-MCN reach survival and migration rate, and MCN-BON reach survival and migration rate. For Snake River wild Chinook all these estimates were reported by four major basins, the Salmon, Imnaha, Grande Ronde, and Clearwater Rivers; for Snake River hatchery steelhead groups only arrival timing and migration rate could be be parsed by these basins. Most years of PIT-tag detection at LGR of CSS analyzed Snake River groups are presented here (1998-2009; see CSS 2009 annual report for years not shown here). Bonneville Dam arrival timing, MCN-BON survival, and fish migration rates for Upper and Mid Columbia River stocks as well as Snake River stocks are shown for the years 2000-2009. For Snake River groups, LGR-MCN reach survivals are the product of LGR-LGS, LGS-LMN, and LMN-MCN reach survivals. Individual reach survival rate estimates may be obtained from the FPC Web site (www.fpc.org; see Chapter 4 for information on accessing the data). Survival in the MCN-BON reach is then LGR-BON reach survival (SR) divided by LGR-MCN reach survival. For all groups, we provide nonparametric bootstrap confidence intervals for the closed form CJS estimators of juvenile reach survival. When presenting median annual fish migration rates, we followed Conover’s recommendations for approximating confidence intervals around a quantile to calculate 90% confidence intervals around the estimate (Conover 1999). Results Annual summaries of out-migration timing, migration rates, and reach survivals Annual out-migration timing (Snake River basin groups) 23 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Figure 2.1 Timing of PIT tag detections at Lower Granite Dam for Snake River Basin wild Chinook analyzed in the CSS. Each panel represents a major basin within the Snake River. The grey line is the averaged values for years 1998-2007; migration years 2008 and 2009 are shown separately. The annual timing of detections of PIT tagged groups from the four major drainages in the Snake River Basin at LGR (1998-2009) are summarized with density plots of PIT tag detections at dams within the hydrosystem in Figure 2.1– 2.11. Within a single migration year and species/rear-type, timing plots showed similar peaks at similar times across groups implying that different stocks are reacting similarly to the same environmental variables within a season. Wild Chinook typically arrive at LGR in early April and finished passing by the end of June (Figure 2.1). The Imnaha River group was frequently the first to arrive at LGR among the Snake River wild Chinook groups. The Imnaha was followed by the Salmon and Grand Ronde River groups whereas the Clearwater River group was typically last and had a more protracted emigration period that extended into July or August. 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Figure 2.2 Timing of PIT tag detections at Lower Granite Dam for five Snake River Basin hatchery Chinook groups analyzed in the CSS. Each panel represents a particular hatchery. The grey line is the averaged values for years 1998-2007; migration years 2008 and 2009 are shown separately. Yearling Chinook were PIT tagged for the CSS at specific hatcheries within the four basins above Lower Granite Dam including the Clearwater, Salmon, Imnaha, and Grande Ronde rivers. Both spring and summer stocks were included. The CSS has PIT tagged and/or analyzed juvenile Chinook from McCall, Rapid River, Dworshak, and Imnaha River hatcheries since 1997, and the Catherine Creek hatchery became available for use in the CSS in 2001. Smolts from both the Imnaha River hatchery (Imnaha stock Chinook) and the Catherine Creek hatchery (Grande Ronde River stock) are tagged at Lookingglass hatchery. The majority of the PIT tagged hatchery Chinook groups emigrating from the Snake River arrived at LGR within a narrower temporal window than did wild Chinook (Figure 2.2). Passage at LGR began later in April and few fish were still passing in June for the five historical CSS hatcheries. Dworshak hatchery fish were often the first to 25 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 arrive at LGR followed by Imnaha and Rapid River groups; Catherine Creek or McCall hatchery groups were often the last to pass LGR. The Dworshak group also had the most protracted emigration of the Chinook hatchery groups. Figure 2.3 Timing of PIT tag detections at Lower Granite Dam for Snake River Basin hatchery Chinook analyzed in the CSS. Each panel represents a particular hatchery added to the CSS for migration year 2009. Outmigration timing in 2009 for the three new hatchery Chinook groups in the CSS are plotted in Figure 2.3. The Clearwater basin releases of hatchery Chinook from Clearwater and Dworshak hatcheries (Figure 2.2) had similar lengthy duration of outmigration as compared to the other six groups. The Pahsimeroi hatchery had the earliest outmigration in 2009 among all eight groups whereas the Sawtooth release was more similar to the Imnaha, Rapid River, McCall, and Catherine Creek releases. 26 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Figure 2.4 Timing of PIT tag detections at Lower Granite Dam for Snake River Basin steelhead analyzed in the CSS; Salmon River A and B steelhead are plotted as an aggregate here. The top left panel shows the wild aggregate and the other panels show hatchery steelhead by basin. The grey line is the averaged aggregate for wild or hatchery steelhead across years 1998-2007 (Snake River), and the aggregate 10-year average is repeated in each hatchery steelhead panel for reference; 2008 and 2009 are shown separately in each panel. Hatchery and wild steelhead passed LGR earlier than most Chinook groups (Figure 2.4) but were somewhat similar in timing to Dworshak or Clearwater hatchery Chinook. Hatchery steelhead generally passed LGR later than the wild steelhead group. When separation by basin was possible for the Snake River hatchery steelhead, there were similar peaks in migrations at similar times but Hell’s Canyon hatchery steelhead had the longest out-migration period as compared to other basins. The Clearwater steelhead had an unusual early peak in 2009 as compared to the other basins. 27 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Annual out-migration timing (Snake River and Columbia River basin groups) Figure 2.5 Timing of PIT tag detections at Bonneville Dam for Snake River Basin and John Day wild Chinook analyzed in the CSS. The top four panels each represent a major basin within the Snake River. The grey line is the averaged values for years 1998-2007 (Snake River) and 2000-2007 (John Day River), migration years 2008 and 2009 are shown separately for each group. Displayed in Figure 2.5 are BON detections of PIT tagged wild Chinook originating from four Snake River basins as well as those from the John Day River. Most wild Snake River PIT tagged Chinook passed BON at a later date and had a more protracted emigration than those originating from the John Day River. The Snake River wild Chinook groups followed a similar order of appearance as at LGR with Imnaha River fish first, followed by Grand Ronde and Salmon River fish, and Clearwater River fish arriving last. 28 1 2 3 4 5 6 7 8 9 10 11 12 13 Figure 2.6 Timing of PIT tag detections at Bonneville Dam for five Snake River Basin hatchery Chinook groups analyzed in the CSS. Each panel represents a particular hatchery. The grey line is the averaged values for years 1998-2007; migration years 2008 and 2009 are shown separately. The timing of 8 Snake River Chinook hatcheries, 2 mid Columbia hatcheries (Cle Elum and Carson) and 1 upper Columbia River hatchery (Leavenworth) are shown in Figure 2.5 – 2.7. In similar migration years, Carson hatchery was the earliest to emigrate followed by Pahsimeroi. Timing among different Snake River groups was more similar than at LGR, and Leavenworth fish were the latest out-migrating group. 29 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Figure 2.7 Timing of PIT tag detections at Bonneville Dam for Snake River Basin hatchery Chinook analyzed in the CSS. Each panel represents a particular hatchery added to the CSS for migration year 2009. 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Figure 2.8 Timing of PIT tag detections at Bonneville Dam for three lower river hatcheries analyzed in the CSS. Each panel represents a particular hatchery added to the CSS for migration year 2009. Each panel represents a particular hatchery. The grey line is the averaged values for years 20002007; migration years 2008 and 2009 are shown separately. 31 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Figure 2.9 Timing of PIT tag detections at Bonneville Dam for Snake River Basin steelhead analyzed in the CSS. The top left panel shows the wild aggregate and the other panels show the hatchery steelhead by basin. The grey line is the averaged aggregate for wild or hatchery steelhead across years 1998-2007 (Snake River), and the aggregate 10-year average is repeated in each hatchery steelhead panel for reference; 2008 and 2009 are shown separately in each panel. For steelhead, BON arrival timing was qualitatively similar to the observations at LGR, with hatchery and wild steelhead passing BON earlier than most Chinook groups (Figure 2.9). Hatchery steelhead generally passed BON later than wild steelhead. As with hatchery and wild Chinook, wild steelhead from the Snake River were generally passing BON later than downriver groups (Figure 2.10). 32 1 2 3 4 5 6 Figure 2.10 Timing of PIT tag detections at Bonneville Dam for wild steelhead analyzed in the CSS. The panels from top to bottom display Snake River, John Day River, and Trout Creek (Deschutes basin) wild steelhead timing. The grey line is the average for Snake River wild steelhead across years 1998-2007; 2008 and 2009 migration years are shown separately in each panel. 33 1 2 3 4 5 6 7 8 9 10 11 Annual out-migration timing (Snake River hatchery sockeye) Figure 2.11 Timing of PIT tag detections at Lower Granite dam for sockeye during 2009 (top two panels) and BON (bottom two panels). Plots are for Oxbow and Sawtooth hatcheries. Annual outmigration timing for Snake River sockeye (Figure 2.11) was very compressed in duration in the latter half of May at LGR, and outmigration was nearly complete at BON before June. This is in contrast to Snake River hatchery steelhead or Chinook which had longer emigration periods that occurred as early as April at LGR and extended into June at BON. 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annual fish migration rate (Snake River basin groups) Figure 2.12 Median fish migration rate from LGR to MCN in km/day for Snake River Chinook from 8 hatcheries (Catherine Creek, Dworshak, Imnaha, McCalls, Rapid River, Clearwater, Pahsimeroi, and Sawtooth) and wild Chinook from 4 drainages (Clearwater River, Grand Ronde River, Imnaha River, and Salmon River). Bars are 90% confidence intervals. Annual fish migration rate expressed in km/day from LGR to MCN for the Snake River Chinook groups is shown in Figure 2.12. In many years, the hatchery Chinook groups emigrated at a faster rate than the wild fish. Among the three new Chinook groups in the CSS, Clearwater hatchery had the second slowest emigration rate in 2009 followed by Dworshak. Sawtooth hatchery had the highest emigration rate through the upper reach in 2009. 35 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Figure 2.13 Median fish migration rate from MCN to BON in km/day for Snake River wild Chinook from four drainages and wild Chinook from the John Day River for the JDA to BON reach. Bars are 90% confidence intervals. Annual fish migration rate (Snake River and Columbia River basin Groups) Fish migration rates in the lower hydrosystem (MCN to BON) for the Snake River wild and hatchery Chinook are plotted alongside lower river groups (LEAV, CLEE, CARS, and John Day wild) in Figures 2.13-2.14. Generally, estimates in the MCN-BON reach are less precise because of lower sample size than for the LGR-MCN reach. Snake River groups had an increased emigration rate in the lower reach than in the LGR-MCN reach. In many cases, emigration rates for the Snake River groups were higher than for lower river groups. As was the case in the upper reach, the faster outmigrating hatchery Chinook groups emigrated faster than wild Chinook groups. 36 1 2 3 4 5 6 7 Figure 2.14 Median fish migration rate from MCN to BON in km/day for Snake River Chinook from 5 hatcheries and Mid Columbia River Chinook from 2 hatcheries. Bars are 90% confidence intervals. 37 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Figure 2.15 Median fish migration rate in km/day for Snake River aggregated hatchery and wild steelhead; the LGR to MCN and the MCN to BON reaches are plotted in the left and right panels respectively. Bars are 90% confidence intervals. Wild steelhead typically emigrated at a faster rate than hatchery steelhead (Figure 2.10-2.11). This trend was opposite that for Chinook, which had higher rates for hatchery than wild. The migration rate for steelhead was higher in the lower river and similar across years to other Snake River groups. When sub-basin/stock groups were possible to estimate for hatchery Steelhead, the Hell’s Canyon group had the slowest emigration rate. Imnaha basin fish were one of the fastest emigrating groups among hatchery steelhead, as was the case for Imnaha basin Chinook among wild Snake River Chinook as well. Figure 2.16 Median fish migration rate for Snake River hatchery steelhead from five basins (Clearwater, Grande Ronde, Hell’s Canyon, Imnaha and Salmon) for the 2008-2009 migration years; Salmon River A and B steelhead are plotted as an aggregate here. The left panel displays the LGR to 38 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 MCN reach. The right panel displays the MCN to BON reach. For comparison, estimates for John Day River basin wild steelhead in the JDA to BON reach are also displayed on the right panel. Annual fish migration rate (Snake River hatchery sockeye) Figure 2.17 Median fish migration rate for Snake River hatchery sockeye from two hatcheries (Oxbow, and Sawtooth) for the 2009 migration year. The left panel displays the migration rate from LGR to MCN and the right panel displays from MCN to BON; both are expressed in km/day. Bars are 90% confidence intervals. Snake River hatchery sockeye emigration rates for 2009 are displayed in Figure 2.17. Historical estimates for the aggregate Snake River sockeye group are shown in Table 2.1; due to small sample sizes these rates are an aggregate of wild and hatchery sockeye from all locations in the Snake River basin. In the upper reach, sockeye from the Oxbow hatchery emigrated at a higher rate than those reported for the aggregate sockeye group from 1998-2008, whereas those from the Sawtooth hatchery were more similar to historical estimates (Table 2.1). As with other Snake River groups, both hatchery groups emigrated faster from MCN to BON than from LGR to MCN. However the rate of emigration for sockeye was much higher than for most other Snake River groups of Chinook or steelhead (Figures 2.12 – 2.16). 39 1 Table 2.1 Emigration rate in the LGR to MCN reach for aggregate Snake River sockeye (19982008). Emigration rate was calculated from median fish travel time in the same reach presented in FPC memo (FPC 26, Jan 2010). Migr. Emigration rate Year LGR to MCN (km/day) 1998 23 1999 37 2000 31 2001 19 2002 27 2003 42 2004 35 2005 17 2006 35 2007 28 2008 34 Geomean 29 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Annual survival (Snake River basin groups) Estimated in-river survival from LGR tailrace to BON tailrace (termed SR) for PIT tagged wild Chinook and five groups of CSS PIT tagged hatchery Chinook showed considerable annual variability, but the SR of both wild populations and hatchery populations tracked closely across years from 1998 to 2007 (Figure 2.11). In the 16-yr time series for wild Chinook and the 13-yr time series for hatchery Chinook, a major drop in in-river survival relative to adjacent years occurred in 2001 (a drought year throughout the Northwest) and 2004, which were both years with low flows in the Snake River basin and no spill at the Snake River collector dams. The same pattern of very low LGR-BON survival (SR) in 2001 and 2004 was also observed for both PIT tagged wild and hatchery steelhead (Figure 2.12). Across years, steelhead survival from LGR to BON was generally lower than Chinook survival. For wild and hatchery steelhead in 2001, the estimated SR was much lower than their Chinook counterparts and included both dead and holdover steelhead as mortalities. The 2009 survival values from LGR to MCN were high values for all groups analyzed; for hatchery and wild steelhead these were the highest values in the time series. The actual values of SR plotted above for both wild and hatchery Chinook and steelhead are presented in Tables 2.2 to 2.5. 40 1 2 3 4 5 Figure 2.18 Trend in in-river survival (SR) for PIT tagged Snake River wild and hatchery spring/summer Chinook in migration years 1994 to 2009. 41 1 2 3 4 Figure 2.19 Trend in in-river survival (SR) for PIT tagged Snake River hatchery and wild steelhead for migration years 1998 to 2009. 42 1 Table 2.2 Estimated in-river survival LGR to BON (SR) of PIT tagged wild Chinook and hatchery Chinook from Rapid River SFH and Dworshak NFH facilities for migration years beginning 1994 (wild stocks) and 1997 (hatchery stocks) to 2009 (with 90% confidence intervals). Aggregate Rapid River SFH Dwoshak NFH Mig. Year Wild Chinook Hatchery Chinook Hatchery Chinook 1994 1995 1996 1997 1998 1999 2000 2002 2003 2004 2005 2006 D 2007 D 2008 D 2009 D Geomean 2001 0.20 A 0.41 B 0.44 A 0.51 A 0.61 C 0.59 0.48 0.61 0.60 0.40 0.48 0.57 0.60 0.46 0.51 0.48 0.23 (0.17 – 0.22) (0.32 – 0.56) (0.35 – 0.55) (0.33 – 0.82) (0.54 – 0.69 ) (0.53 – 0.68) (0.41 – 0.58) (0.52 – 0.76) (0.52 – 0.69) (0.33 – 0.51) (0.39 – 0.61) (0.43 – 0.79) (0.57 – 0.63) (0.36 – 0.60) (0.43 – 0.61) (0.20 – 0.27) 0.33 A 0.59 C 0.57 0.58 0.71 0.66 0.35 0.54 0.55 C 0.63 0.56 0.71 0.55 0.33 (0.24 – 0.45) (0.52 – 0.66) (0.49 – 0.67) (0.48 – 0.83) (0.60 – 0.84) (0.57 – 0.78) (0.27 – 0.51) (0.42 – 0.69) (0.51 – 0.61) (0.56 – 0.72) (0.45 – 0.72) (0.61 – 0.85) (0.28 – 0.40) 0.49 A 0.51 C 0.54 0.48 0.62 0.68 0.50 0.51 0.54 C 0.67 0.40 0.44 0.53 0.24 (0.31 – 0.80) (0.44 – 0.58) (0.47 – 0.65) (0.40 – 0.65) (0.54 – 0.72) (0.58 – 0.81) (0.40 – 0.66) (0.42 – 0.63) (0.49 – 0.59) (0.60 – 0.75) (0.32 – 0.55) (0.38 – 0.52) (0.20 – 0.30) A to C Footnote shows percent of reach with a constant “per/mile” survival rate applied (A = 77% expansion LMN to BON; B = 51% expansion MCN to BON; C = 25% expansion JDA to BON). D Migration years 2006 and later use reach survival rate estimates of combined T and R groups. 2 3 Table 2.3 Estimated in-river survival LGR to BON (SR) of PIT tagged hatchery Chinook from Catherine Ck AP, Imnaha R AP, and McCall SFH facilities for migration years 1997 to 2009 (with 90% confidence intervals). Catherine Ck AP Imnaha R AP McCall SFH Hatchery Chinook Hatchery Chinook Hatchery Chinook Mig. Year 1997 1998 1999 2000 2002 2003 2004 2005 2006 D 2007 D 2008 D 2009 D Geomean 2001 0.65 0.62 C 0.48 C 0.51 C 0.48 C 0.72 0.48 0.54 0.55 0.25 (0.44 – 1.06) (0.51 – 0.74) (0.34 – 0.72) (0.37 – 0.80) (0.38 – 0.61) (0.53 – 1.07) (0.29 – 1.11) (0.40 – 0.84) (0.18 – 0.37) 0.31 A 0.53 C 0.54 0.57 0.50 0.70 C 0.56 C 0.58 C 0.50 C 0.69 0.34 0.67 0.53 0.37 A to C (0.20 – 0.49) (0.46 – 0.62) (0.42 – 0.75) (0.43 – 0.83) (0.41 – 0.66) (0.62 – 0.80) (0.44 – 0.73) (0.47 – 0.78) (0.43 – 0.58) (0.57 – 0.88) (0.25 – 0.49) (0.51 – 0.94) (0.27 – 0.61) 0.43 A 0.56 C 0.52 0.61 0.58 0.70 0.44 0.53 0.60 C 0.82 0.36 0.57 0.55 0.27 (0.32 – 0.59) (0.50 – 0.64) (0.46 – 0.61) (0.51 – 0.83) (0.51 – 0.68) (0.62 – 0.77) (0.35 – 0.59) (0.45 – 0.65) (0.53 – 0.67) (0.73 – 0.94) (0.30 – 0.45) (0.50 – 0.67) (0.22 – 0.34) Footnote shows percent of reach with a constant “per/mile” survival rate applied (A = 77% expansion LMN to BON; B = 51% expansion MCN to BON; C = 25% expansion JDA to BON). D Migration years 2006 and later use reach survival rate estimates of combined T and R groups. 43 1 Table 2.4 Estimated in-river survival LGR to BON (SR) of PIT-tagged steelhead for wild stocks from 1997 to 2009 and hatchery stocks from 1997 to 2007 (with 90% confidence intervals). Aggregate Aggregate Mig. Year Wild Steelhead Hatchery Steelhead 1997 1998 1999 2000 2002 2003 2004 2005 2006 D 2007 D 2008 D 2009 D Geomean 2001 0.52 C (0.28 – 1.00) 0.54 C (0.48 – 0.62) 0.45 (0.38 – 0.54) C 0.30 (0.28 – 0.33) 0.52 (0.41 – 0.69) 0.37 (0.31 – 0.44) 0.18 B (0.13 – 0.26) 0.25 C (0.20 – 0.34) 0.58 C (0.50 – 0.67) 0.38 (0.31 – 0.48) 0.42 (0.35 – 0.52) 0.70 C (0.58 – 0.84) 0.41 0.038 (0.027 – 0.059) 0.40 C (0.26 – 0.71) 0.64 (0.47 – 1.00) 0.45 (0.39 – 0.53) C 0.22 (0.19 – 0.25) 0.37 (0.29 – 0.49) 0.51 (0.42 – 0.61) 0.17 B (0.13 – 0.23) 0.36 C (0.30 – 0.46) 0.62 C (0.56 – 0.69) 0.49 (0.41 – 0.60) 0.49 (see Table 2.5) 0.67 (see Table 2.5) 0.42 0.038 (0.023 – 0.082) A to C Percent of reach with a constant “per mile” survival rate applied (A = 77% expansion LMN to BON; B = 51% expansion MCN to BON; C = 25% expansion JDA to BON). D Migration years 2006 and later use reach survival rate estimates of combined T and R groups. 2 3 Table 2.5 Estimated in-river survival LGR to BON (SR) of PIT tagged steelhead for wild stocks from 1997 to 2009 and hatchery stocks from 1997 to 2007 (with 90% confidence intervals). Run Aggregate Mig. Year1 Drainage Type Hatchery Steelhead 1 4 5 6 7 8 9 10 2008 2008 2008 2008 2008 Clearwater R Grande Ronde R Imnaha R Salmon R Salmon R 2009 2009 2009 2009 2009 2009 Clearwater R Grande Ronde R Imnaha R Salmon R Salmon R Mainstem below HCD B A (Wallowa) A A B Geomean B A (Wallowa) A A B A Geomean 0.39 0.56 0.55 0.40 0.57 0.49 0.61 0.70 0.67 0.70 0.69 0.66 0.67 (0.36 – 0.42) (0.46 – 0.72) (0.41 – 0.76) (0.35 – 0.46) (0.44 – 0.76) (0.55 – 0.68) (0.61 – 0.82) (0.55 – 0.86) (0.62 – 0.81) (0.59 – 0.86) (0.50 – 0.96) Migration years 2006 and later use reach survival rate estimates of combined T and R groups. Further partition of these survival rates into the LGR-MCN reach and MCN-BON reach are plotted in Figures 2.2 and 2.21. The values of individual in-river survival rates 44 1 2 3 4 5 6 7 8 9 10 11 12 13 14 between each monitored reach from LGR to BON may be obtained from the FPC Web site (www.fpc.org; see Chapter 4 for information on accessing the data). Figure 2.20 Annual estimates of reach survivals from LGR to MCN for five Snake River Chinook hatcheries, wild Chinook, hatchery steelhead and wild steelhead (2000-2007). Estimates were calculated using the CJS model; confidence intervals are 90% non-parametric bootstrapped intervals. Survival estimates from LGR to MCN and MCN to BON are displayed in Figure 2.20 and 2.21 for Snake River originating Chinook groups. In the upper hydrosystem hatchery Chinook often survived at a higher rate than wild Chinook and Chinook groups survived at a higher rate than steelhead groups, except for 2009 (Figure 2.23-2.24). In the lower hydrosystem, there was more variability surrounding the survival estimates but the patterns were similar for Chinook. 45 1 2 3 4 5 6 7 8 Figure 2.21 Annual estimates of reach survivals from MCN to BON for five Snake River Chinook hatcheries, wild Chinook, hatchery steelhead and wild steelhead (2000-2007). Estimates were calculated using the CJS model; confidence intervals are 90% non-parametric bootstrapped intervals. 46 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Annual survival (Snake River and Columbia River basin groups) Figure 2.22 Annual estimates of reach survivals from MCN to JDA for five Snake River Chinook hatcheries, and two Columbia River Chinook hatcheries (2000-2007). Estimates were calculated using the CJS model; confidence intervals are 90% non-parametric bootstrapped intervals. Survival estimates through the entire lower reach (MCN to BON) were not stable for the Cle Elum (CLEE) and Leavenworth (LEAV) hatchery Chinook groups. However, we were able to estimate survival in the MCN to JDA reach and, except for 2008 when CLEE and LEAV survival estimates exceeded one, these are compared with those for Snake River hatchery Chinook groups within the MCN to JDA reach (Figure 2.22). Point estimates for Snake River groups were typically higher than for Columbia River groups within the same year. 47 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Figure 2.23 Annual estimates of reach survivals from LGR to MCN (left panel) and MCN to BON (right panel) for Snake River steelhead hatcheries by basin of release (2008-2009). Estimates were calculated using the CJS model; confidence intervals are 90% non-parametric bootstrapped intervals. Figure 2.24 Annual estimates of reach survivals from LGR to MCN (left panel) and MCN to BON (right panel) for Snake River steelhead hatcheries by basin of release (2008-2009). Estimates were calculated using the CJS model; confidence intervals are 90% non-parametric bootstrapped intervals. For steelhead groups in the LGR to MCN reach, wild steelhead often survived at a higher rate than hatchery steelhead (Figure 2.23-2.24). One would expect steelhead to follow a similar pattern of lower survival in the MCN to BON reach. However, estimates for the MCN to BON reach were imprecise due to smaller sample size than for Chinook groups, and thus some may be of limited use for a comparative evaluation (Figure 2.23). For most groups the 2009 survival estimates were the highest in the time series. 48 1 2 3 4 5 6 7 8 9 10 11 12 13 Annual survival (Snake River and hatchery sockeye) Figure 2.25 Annual estimates of reach survivals from LGR to MCN (left panel) and MCN to BON (right panel) for Snake River hatchery sockeye (2009). Estimates were calculated using the CJS model; confidence intervals are 90% non-parametric bootstrapped intervals. Snake River hatchery sockeye survival rates for 2009 are displayed in Figure 2.25. Historical estimates for the aggregate Snake River sockeye group are shown in Table 2.6; due to small sample sizes these rates are an aggregate of wild and hatchery sockeye from all locations in the Snake River basin. In the upper reach, sockeye from both Oxbow and Sawtooth hatcheries had a higher point estimate of survival than those reported for the aggregate sockeye group from 1998-2008 (Table 2.6). Table 2.6 Juvenile survival for LGR to MCN reach for aggregate Snake River sockeye (1998-2008). Survival data are from FPC memo (FPC 26, Jan 2010). Juvenile Migr. 95% Con. Int. Survival Lower Upper Year (LGR-MCN) Limit Limit 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Geomean 0.6 0.22 0.98 0.63 0.64 0.26 0.5 0.71 N/A 0.45 0.86 0.62 0.67 0.42 0.37 0.06 0.35 0.5 N/A 0.13 0.47 0.38 0.43 0.84 0.91 0.46 0.66 0.91 N/A 0.77 1.25 0.86 0.9 0.57 49 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Discussion In this chapter we provided an extensive synthesis of the patterns of variation in juvenile yearling Chinook and steelhead passage timing at key dams, emigration rates, and survival within key reaches of the hydrosystem. These metrics are presented as annual estimates in management-oriented groups and provide a consistent time-series of demographic data to inform research, management, and evaluation of these stocks. Some general statements can be made from these data. Within a single species but among groups (e.g. 8 hatchery groups of Snake River Chinook in 2009) there were similar seasonal peaks in arrival timing at across all groups, perhaps suggesting that all stocks were reacting similarly to environmental influences. In general, wild Chinook arrived at LGR before hatchery Chinook and wild steelhead before hatchery steelhead. In 2009, Snake River sockeye arrived at LGR after many groups but displayed the most compressed emigration window and emigrated at a higher rate than most other Snake River stocks. Most Snake River stocks emigrated at a higher rate in the lower hydrosystem (MCN to BON) than the upper hydrosystem (LGR to MCN). Snake River groups often emigrated more quickly through the lower hydrosystem than the same species originating from the Columbia River basin. Survival for the Snake River stocks in the LGR to MCN reach generally showed an increase over the time series with the highest survival for steelhead occurring in 2009. These stocks, where discernable, had a higher survival in the upper reach (LGR to MCN) than the lower reach (MCN to BON) though many lower reach estimates have low precision and were not statistically different. Point estimates for Snake River groups were typically higher than for Columbia River groups within the same year. Among the two sockeye groups in 2009, the reach survival point estimates for the Sawtooth group were higher than for the Oxbow group. 50 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Chapter 3 Effects of the in-river environment on juvenile travel time, instantaneous mortality rates and survival The CSS is an important component of ongoing Research, Monitoring and Evaluation (RM&E) and Data Management studies in the Columbia River basin. This long-term study provides specific information on management actions in the region, specifically the role of the smolt transportation program, flow augmentation, and spill for the recovery of listed salmon and steelhead stocks. In addition to providing a time series of SAR data (see chapter 4 and 6), the CSS provides data on smolt out-migration timing, juvenile migration rates and travel times, juvenile reach survivals, and evaluates these parameters for the purpose of informing management and recovery decisions related to those stocks. As a long-term study, the CSS has included PIT-tagged smolts from a variety of basins, locations, species and rear-types in an effort to arrive at, among other goals, a holistic view of juvenile demographic parameters and their relationships to hydrosystem management actions in the FCRPS. This chapter summarizes data collected on groups of juvenile salmonids from the Snake River basin, which consisted of spring/summer Chinook salmon, steelhead and sockeye salmon. This chapter updates the multiple regression models of fish travel time, instantaneous mortality rates and survival rates from Chapter 3 of the 2009 Annual Report (Tuomikoski et al. 2009). These analyses address an interest of the ISAB/ISRP for finer scale analyses of the relationships between survival and specific operational actions or environmental features (ISAB 2006). In this chapter we continue the process of summarizing and synthesizing the results that have been obtained to date through the CSS on the responses of juvenile yearling Chinook salmon and steelhead to conditions experienced within the hydrosystem. These analyses provide an example of how the CSS PIT-tag results could be used in a predictive fashion to characterize the effects of management actions on fish travel times and in-river juvenile survival rates, while directly accounting for measurement uncertainty and environmental variability. Methods Study area and definitions In this chapter, we define the hydrosystem as the overall reach between Lower Granite Dam (LGR) and Bonneville (BON) Dam. There are six dams between LGR and BON: Little Goose (LGS), Lower Monumental (LMN), Ice Harbor (IHR), McNary (MCN), John Day (JDA), and The Dalles (TDA). We divided the hydrosystem into two reaches for summarizing fish travel time, instantaneous mortality rates and survival: LGR-MCN and MCN-BON. We define fish travel time (FTT) as the time spent migrating the LGR-MCN or MCN-BON reach and expressed this in days. We used Cormack-Jolly-Seber (CJS) methods to estimate survival rates through the two reaches based on detections at the dams and in a PIT-tag trawl operating below BON (Cormack 1964, Jolly 1965, Seber 1965, Burnham et al. 1987). 51 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Multiple regression modeling The goal of the multiple regression models is to evaluate finer-scale analyses of the relationships between survival and specific operational actions or environmental features during the juvenile outmigration. Towards this goal, we calculated and summarized within-year (weekly or multi-weekly) travel time, instantaneous mortality and survival rate estimates for juvenile yearling Chinook and steelhead across years of the CSS. We also calculated and summarized seasonal estimates of travel time, instantaneous mortality rates and survival rates for sockeye. The yearling Chinook, steelhead and sockeye used in this analysis consisted of fish PIT-tagged both at hatcheries and fish traps upstream of Lower Granite Dam (LGR) and those tagged and released at LGR. Due to sufficient numbers of PIT-tagged hatchery and wild yearling Chinook available, analyses in the LGR-MCN reach were conducted separately for hatchery and wild yearling Chinook. Due to the limited number of PIT-tagged steelhead available, hatchery and wild steelhead were combined for analyses in the LGR-MCN reach. Similarly, hatchery and wild sockeye are combined for analyses in the LGR-MCN reach. Analyses on the MCN-BON reach included hatchery and wild yearling Chinook and steelhead from the Snake River, hatchery-marked fish from the Mid-Columbia River, and fish marked and released at MCN. Fish travel time We utilized a cohort-based approach for characterizing fish travel times for weekly groups of juvenile Chinook salmon and steelhead. Individual fish detected at LGR with PIT-tags were assigned to a weekly cohort group (i) according to the week of their detection. Cohorts were identified by the Julian day of the midpoint of the weekly cohort. For example, the April 1-7 release cohort was identified by Julian day = 94 (April 4). We calculated fish travel time as the number of days between releases at LGR until detection at MCN for each fish subsequently detected at MCN. For statistical reasons (described below), we calculated the mean FTTi for each weekly release cohort instead of the median FTT that was presented in previous reports (Schaller et al. 2007, Tuomikoski et al. 2009). In preliminary analyses, we used Box-Cox power transformations to determine whether the FTTi data needed to be transformed in order to better approximate normality of the residuals in subsequent regressions. These preliminary analyses indicated that a log-transformation was most appropriate for both the Chinook and steelhead data. We calculated mean FTTi for each weekly release cohort of both yearling Chinook and steelhead, in both the LGR-MCN and MCN-BON reaches. Because the number of PIT-tagged sockeye was low and the juvenile sockeye migration season is relatively narrow, we calculated a seasonal estimate of LGR-MCN FTT for sockeye. There were not sufficient numbers of PIT-tagged Snake River sockeye in the MCN-BON reach to calculate reliable estimates of FTT. For yearling Chinook, we calculated mean FTTi for eight weekly cohorts from April 1 through May 26 in the LGR-MCN reach. Separate estimates were developed for hatchery and wild rearing types of yearling Chinook. In the MCN-BON reach, hatchery and wild yearling Chinook were combined and we calculated mean FTTi for six weekly cohorts from April 26 through June 5. For steelhead, we calculated mean FTTi for six 52 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 weekly cohorts from April 17 through May 28 in the LGR-MCN reach. In the MCNBON reach, we calculated mean FTTi for six weekly cohorts of steelhead from April 27 through June 7. Hatchery and wild rearing types of steelhead were combined for both reaches. Survival We estimated the survival rates for each weekly cohort of wild Chinook, hatchery Chinook and the combined hatchery and wild steelhead in the LGR-MCN reach using standard CJS methods over migration years 1998-2009. We also estimated seasonal survival rates for sockeye in the LGR-MCN reach over 1998-2009. Due to lower numbers of PIT-tagged fish detected and released at MCN, we developed survival estimates for three, two-week cohorts for yearling Chinook and two, three-week cohorts for steelhead in the MCN-BON reach over migration years 1999-2009. We calculated Chi-square adjusted variances (using the ĉ variance inflation factor) for each survival rate estimate ( Ŝ ) (Burnham et al. 1987:244-246). Using this delineation for the cohorts, the average coefficient of variation (CV) across the weekly survival rate estimates in the LGR-MCN reach was 7% for wild yearling Chinook, 7% for hatchery yearling Chinook, 6% for steelhead (combined hatchery and wild) and 22% for sockeye (seasonal estimates, combined hatchery and wild). In the MCN-BON reach, the average CV across the survival rate estimates was 14% for yearling Chinook (hatchery and wild combined, twoweek cohorts) and 27% for steelhead (hatchery and wild combined, three-week cohorts). Each release cohort was identified by the Julian day of the midpoint of the cohort. Instantaneous mortality rates In 2003, the ISAB offered the suggestion that “an interpretation of the patterns observed in the relation between reach survival and travel time or flow requires an understanding of the relation between reach survival, instantaneous mortality, migration speed, and flow” (ISAB 2003-1). Consistent with that suggestion, we developed an approach for estimating instantaneous mortality rates for juvenile salmonids (Schaller et al. 2007, Tuomikoski et al. 2009). Ricker (1975) provides a numerical characterization of survival, also known as the exponential law of population decline (Quinn and Deriso 1999): N S t e Zt , [3.1] N0 where S is a survival rate, N t is the number of individuals alive at time t, N 0 is the number of individuals alive at time t = 0, and Z is the instantaneous mortality rate, in units of t 1 . Eqn. 3.1 is the solution to the differential equation N ZN , [3.2] t and the instantaneous mortality rate Z is interpreted as the rate of exponential population decline. Eqn. 3.1 has been called the “first principle” or “first law” of population dynamics (Turchin 2003), and serves as a foundational basis for most fisheries population assessment models (Quinn and Deriso 1999). 53 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 The exponential law of population decline provides a useful framework for understanding the interrelationships between instantaneous mortality rates, time, and survival. Over a fixed period of time, an increase in Z will result in lower survival over that time period. Similarly, for a fixed Z, survival will decrease with increasing time. At time t = 0, survival is 1.0 and survival declines toward zero as t increases. If instantaneous mortality rates vary over time, Z represents the arithmetic mean mortality rate over the time period (Keyfitz 1985:18-19). This property of Z may be useful for capturing mortality rates for smolts in the Columbia Basin, which may experience different mortality rates over time. For example, if mortality rates experienced through a reservoir differ from mortality experienced through a dam, then the instantaneous mortality rate Z represents the arithmetic mean mortality rate over that period of migration through the reservoir and dam combination. Rearranging Eqn. 3.1, Z can be estimated as log e ( Sˆ ) Zˆ . [3.3] t In our application, we calculated instantaneous mortality rates (in units of d-1) for each survival cohort using Eqn. 3.3. We used the CJS estimates of survival for each cohort ( Ŝ i ) in the numerator and used the mean FTˆTi in the denominator of Eqn. 3.3. In previous reports (Schaller et al. 2007, Tuomikoski et al. 2009) we used median FTˆT in i the denominator of Eqn. 3.3. However, simulation analyses indicated that using mean FTˆTi in the denominator of Eqn. 3.3 provides more accurate estimates of the underlying instantaneous mortality rate than using median FTˆT (Steven Haeseker, USFWS, 21 22 23 24 25 unpublished data). While individuals in each release cohort have variable individual FTT’s, we used the mean FTˆTi ' s in the denominator of Eqn. 3.3 to characterize the cohort-level central tendency in the amount of time required to travel a reach. Combining the cohort-level survival rate estimates ( Ŝ i ) with the cohort-level mean FTˆTi 26 27 28 estimates, we estimated the cohort-level instantaneous mortality rates ( Ẑ i ) using Eqn. 3.3. Both log e ( Sˆ i ) and mean FTˆTi are random variables subject to sampling and 29 30 31 32 process error. To calculate the variance of Ẑ i , we used the formula for the variance of the quotient of two random variables (Mood et al. 1974): 33 34 35 36 37 38 39 i log(S ) log(S ) var(Zˆi ) var FTT FTT 2 var[ log(S )] var[FTT ] 2cor ( log(S ), FTT ) var[ log(S )] var[FTT ] , log(S ) 2 log(S ) FTT FTT 2 [3.4] To estimate the variance of –log(S), we used the approximation provided by Blumenfeld (2001) for log-normally distributed random variables: [3.5] var[ log e ( S )] log e (1 [CV ( S )]2 ) . Environmental variables 54 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 The environmental variables associated with each cohort were generated based on fish travel time and conditions at each dam along the reaches. Travel time for each group between dams was estimated, and we calculated the average spill percentage, temperature (based on tailwater total dissolved gas monitoring data, downloaded from the COE website (http://www.nd-wc.usace.army.mil/perl/dataquery.pl) and total water transit time (WTT) as indicators of conditions each group experienced while passing through the reach. Water transit time was calculated by dividing the total volume of reservoirs by the flow rate, and with adjustments in McNary pool to account for Columbia River versus Snake River flows. Conditions at downstream dams were averaged over a seven-day window around the median passage date at each dam, and the travel time to the next dam was used to adjust the start date of the calculations. For example, steelhead travel time from LGR to LGO for the earliest release cohort in 2005 (detected at LGR from 4/17 to 4/23) was estimated to be 5.0 days based on 378 detections. Average environmental variables over the time period of April 22 to April 28 at LGO were then calculated. At each downstream dam, environmental variables were calculated in a similar manner. Since no PIT-tag detection data were available until 2005 at IHR, travel time to IHR was estimated as 43% of the total travel time from LMN to MCN (corresponding to the distance to IHR relative to the distance to MCN). The overall reach environmental variables were the average of these dam-specific calculated values for spill percentage and temperature, whereas for water transit time the sub-reach values were summed to estimate the total reach water transit time. In addition to these environmental predictor variables, we also used Julian date as a predictor variable to help capture seasonal effects not reflected in these environmental variables. We use Julian date of release to characterize effects such as degree of smoltification, photoperiod, predator abundance/activity, or fish length that may demonstrate a consistent pattern within- and across-years, but is not already captured by the other environmental variables. The use of Julian date of release as an attempt to capture seasonal effects is a common modeling strategy for these data (Berggren and Filardo 1993, Smith et al. 2002, Williams et al. 2005). We also developed a variable that enumerated the number of surface passage structures (e.g., removable spillway weirs [RSWs] or temporary spillway weirs [TSWs]) in place over the years of observation. 44 where 0 , 1 ,..., n are estimated parameters used to describe the relationship between 45 environmental variables X1, X2,…, Xn and log(FTT), and i ~ N (0, 2 ) . In preliminary Variable selection and model building We used linear regression techniques to evaluate the associations between the environmental variables and mean FTT and instantaneous mortality (Z). We used Akaike’s Information Criterion adjusted for small sample sizes (AICc) for evaluating model fit and variable selection. As mentioned above, Box-Cox power transformations indicated that a log-transformation was most appropriate for the FTT data. Therefore we modeled log(FTT) as the dependent variable in all analyses. The loge transformations were also implemented to help reduce heteroscedasticity. These regressions were of the form: log( FTˆTi ) 0 1 X 1,i 2 X 2 ,i ... i , [3.6] 55 5 analyses we also utilized Box-Cox power transformations to examine whether the Ẑ i should be transformed. These preliminary analyses indicated that a square-root transformation was most appropriate, therefore we proceeded to conduct the regressions using sqrt ( Zˆ i ) as the dependent variable. These regressions were of the form: sqrt ( Zˆ ) X X ... , [3.7] 6 where 0 , 1 ,..., n are estimated parameters used to describe the relationship between 7 environmental variables X1, X2,…, Xn and sqrt(Z), and i ~ N (0, 2 ) . Because there 1 2 3 4 8 9 10 11 12 13 14 15 16 17 18 19 20 21 i 1 1 ,i 2 i 2 ,i were large differences in the precision of the Ẑ i , we used inverse-variance weighting in the fitting process for modeling instantaneous mortality rates. In addition, there was considerable model selection uncertainty (i.e., multiple models fitting the data similarly well) in the models for Ẑ i in the cases of sockeye in the LGR-MCN reach and both Chinook and steelhead in the MCN-BON reach. In these cases, we used model-averaged predictions for the Ẑ i (Burnham and Anderson 2002) to account for the model selection uncertainty. Survival modeling approach Our approach for modeling survival rates utilized the exponential mortality model (Eqn. 3.1), allowing the predicted instantaneous mortality rates Zi and the mean FTTi ' s to vary in response to environmental factors. Using our best-fit models for predicting Z *i and FTT *i (Eqns. 3.6 and 3.7), predicted survival rates were estimated as: * * S *i e Z i FTT i , 22 23 0 where Z * i is the predicted instantaneous mortality rate, FTT [3.8] * i is the predicted mean * i 24 FTTi, and S is the predicted survival rate for period i, calculated by exponentiating the 25 26 27 28 29 30 31 32 33 34 negative product of Z *i and FTT *i . Results 35 ˆ , Zˆ and Sˆ of cohorts of juvenile yearling Chinook, Estimates of mean FTT i i i steelhead and seasonal estimates of sockeye along with predicted values for these parameters are shown in Figures 3.1, 3.3, and 3.5 (LGR-MCN reach) and Figures 3.2, ˆ , Zˆ and Sˆ varied considerably over the 3.4, and 3.6 (MCN-BON reach). Mean FTT i i i period of 1998-2009 in the LGR-MCN each, both within- and across-years (Figures 3.1, ˆ generally decreased over the 3.3, 3.5). While there were some special cases, mean FTT i ˆ season, S either increased or decreased over the season, and Zˆ increased over the 36 37 38 season. Within-year estimates of Sˆi varied by up to 39 percentage points for both wild Chinook and steelhead, and by up to 32 percentage points for hatchery Chinook. Across all years and cohorts, estimates of Sˆi varied by up to 64 percentage points for Chinook i i 56 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 and 76 percentage points for steelhead. The large within- and across-year variation in Sˆi demonstrates a high degree of contrast in Sˆ over this 1998-2009 timeframe. i In the MCN-BON reach, cohorts of yearling Chinook and steelhead demonstrated ˆ , Zˆ and Sˆ patterns similar to those observed in the LGR-MCN within-year mean FTT i i i reach, varying considerably both within- and across-years (Figures 3.2, 3.4, and 3.6). For ˆ , generally decreased over the migration season. Yearling both species, mean FTT i ˆ , ranging Chinook in 2001 demonstrated the largest within-year variation in mean FTT i from 22 days early in the season to 8 days late in the season (Figure 3.2). Due to imprecision in the estimates of Sˆi , general patterns in the estimates of Sˆi and Zˆi in the MCN-BON reach were difficult to discern (Figures 3.4 and 3.6). For both Chinook and steelhead, Zˆi generally increased over the season. Steelhead Sˆi generally decreased over the season, but no general patterns were evident for Chinook Sˆ . i The best fitting models (based on AICc) for mean FTT consistently had model forms with Julian day, water transit time and spill. The signs of the model coefficients for these variables indicated that juvenile Chinook, steelhead and sockeye all migrated faster as water velocity increased (i.e., WTT was reduced) and as spill percentages increased. Juvenile Chinook and steelhead also migrated faster as the season progressed. Because we were not able to develop within-season estimates of FTT for sockeye, we were not able to determine whether sockeye share similar increases in migration speed as Julian day increases. For steelhead in the LGR-MCN reach and the MCN-BON reach, we observed a significant effect of the number of surface passage structures in place on FTT, with the increasing number of surface passage structures at Little Goose, Lower Monumental, Ice Harbor and John Day dams reducing steelhead FTTs. We also identified a significant effect (P < 0.001) of the percentage of hatchery steelhead in the LGR-MCN reach, with hatchery steelhead taking two days longer on average to migrate through the LGR-MCN reach than wild steelhead. The models that were developed for all species captured a very high degree of the variation in mean FTT of all species (Table 3.1). The best fitting model (based on AICc) for sockeye FTT contained only spill. The best fitting models (based on AICc) for Z also had model forms primarily with Julian day, water transit time and spill. For steelhead in the LGR-MCN reach, the lowest AICc model contained Julian day, spill and the number of surface passage structures, with Z predicted to increase with Julian day and Z predicted to decrease as percent spill increased or the number of surface passage structures increased. For wild Chinook in the LGR-MCN reach, the lowest AICc model contained Julian day, WTT, an interaction between Julian day and WTT, and the number of surface passage structures, with Z predicted to increase with Julian day or with increases in WTT and Z predicted to decrease as the number of surface passage structures increased. For hatchery Chinook in the LGR-MCN reach, the lowest AICc model contained Julian day and spill, with Z predicted to increase with Julian day and Z predicted to decrease as spill increases. The lowest AICc model for sockeye in the LGR-MCN reach contained only WTT, with Z predicted to increase as WTT increases. For combined hatchery and wild Chinook in the MCN-BON reach, the lowest AICc model contained Julian day and WTT, with Z predicted to increase with Julian day and with increases in WTT. For combined hatchery 57 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 and wild steelhead in the MCN-BON reach, the lowest AICc model contained only temperature, with Z predicted to increase as water temperatures increase. However, the survival estimates for steelhead in the MCN-BON reach were the least precise among those species-reach combinations that we examined, so some caution is warranted in judging the relative importance of temperature versus other factors for steelhead in this reach. Combining the models for predicting mean FTT and Z resulted in generally high accuracy in predicting reach survival rates for the species-reach combinations that we examined (Table 3.1). As mentioned above, the models developed for FTT explained a very high proportion of the observed variation in FTT. Although the models for Z explained a lower proportion of the variability in Z, when the models for FTT and Z were combined to make predictions for survival, a relatively high proportion of the variation was captured. These results show that the models developed by the CSS are effective for characterizing and understanding sources of variation in the migration rates, mortality rates and survival rates of Chinook, steelhead and sockeye. 58 1 2 3 4 5 6 7 8 9 10 Figure 3.1 Estimates of mean FTT (in days, blue squares) and predicted mean FTT (yellow circles) for weekly release groups of wild Chinook (upper panel), hatchery Chinook (second panel), combined hatchery and wild steelhead (third panel) and seasonal estimates of combined hatchery and wild sockeye (fourth panel) in the LGR-MCN reach, 1998-2009. Error bars represent the 95% confidence limits on the mean FTT. 59 1 2 3 4 5 Figure 3.2 Estimates of mean FTT (in days, blue squares) and predicted mean FTT (yellow circles) for weekly release groups of combined hatchery and wild Chinook (upper panel) and combined hatchery and wild steelhead (lower panel) in the MCN-BON reach, 1999-2009. Error bars represent the 95% confidence limits on the mean FTT. 60 1 2 3 4 5 6 7 Figure 3.3 Estimates of instantaneous mortality rates, Z (d-1, blue squares), and predicted Z (yellow circles) for weekly release groups of wild Chinook (upper panel), hatchery Chinook (second panel) combined hatchery and wild steelhead (third panel) and seasonal estimates of combined hatchery and wild sockeye (fourth panel) in the LGR-MCN reach, 1998-2009. Error bars represent the 95% confidence limits on Z. 61 1 2 3 4 5 6 7 8 Figure 3.4 Estimates of instantaneous mortality rates, Z (d-1, blue squares) and predicted Z (yellow circles) for two-week release groups of combined hatchery and wild Chinook (upper panel) and for three-week release groups of combined hatchery and wild steelhead (lower panel) in the MCN-BON reach, 1999-2009. Error bars represent the 95% confidence limits on Z. 62 1 2 3 4 5 6 7 8 Figure 3.5 Estimates of in-river survival rates(blue squares) and predicted survival rates (yellow circles) for weekly release groups of wild Chinook (upper panel), hatchery Chinook (second panel) combined hatchery and wild steelhead (third panel) and seasonal estimates of survival for combined hatchery and wild sockeye in the LGR-MCN reach, 1998-2009. Error bars represent the 95% confidence limits on the survival rates. 63 1 2 3 4 5 6 7 8 Figure 3.6 Estimates of in-river survival rates (blue squares) and predicted survival rates (yellow circles) for two-week release groups of combined hatchery and wild Chinook (upper panel) and for three-week release groups of combined hatchery and wild steelhead (lower panel) in the MCN-BON reach, 1999-2009. Error bars represent the 95% confidence limits on the survival rates. 64 1 Table 3.1 Proportions of variation explained (r2 values) in relationships characterizing Chinook, steelhead and sockeye mean FTT, instantaneous mortality rates (Z) and in-river survival rates within the LGR-MCN reach and the MCN-BON reach. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Reach LGR-MCN LGR-MCN LGR-MCN LGR-MCN Species & Rearing Type CHN (W) CHN (H) STH (H&W) SOX (H&W) MCN-BON MCN-BON CHN (H&W) STH (H&W) mean FTT 0.84 0.83 0.92 0.65 Z 0.43 0.28 0.49 0.35 Survival 0.55 0.41 0.79 0.68 0.96 0.92 0.15 0.55 0.25 0.73 Discussion In this analysis we provided an extensive synthesis of the patterns of variation in juvenile yearling Chinook, steelhead and sockeye fish travel time and survival within the hydrosystem. In addition to these commonly-used metrics of fish travel time and survival, we also developed and reported estimates of instantaneous mortality rates, along with estimates of precision for those rates. We observed substantial variation in mean fish travel time, survival, and instantaneous mortality rates both within- and across-years. The models that were developed for characterizing the effects of various environmental and management factors on mean fish travel times, survival rates, and instantaneous mortality rates capitalized on this variation and demonstrated a high degree of accuracy. We see these models as powerful tools for continued development, evaluation, and refinement of alternative hypotheses on the effects of various environmental and management factors on smolt survival and migration rates. Particularly in the MCNBON reach, we found that estimates of survival have substantial uncertainty. As a result, estimates of instantaneous mortality rates in this reach also have substantial uncertainty. Although we were able to develop models that explained a substantial proportion (2573%) of the variation in MCN-BON survival rates, questions remain as to which factors are primarily important for determining survival in the lower river. We see the only way to resolve the remaining questions is to invest in more PIT-tagging efforts for reducing the uncertainty in the lower reach. We believe that the models developed here provide some useful tools for predicting the effects of alternative hydrosystem management actions. Some of these could include changes in water volume, volume shaping/timing, spill levels and timing, or changes in reservoir elevations. At a minimum, these models provide a basis for hypothesis development for use in adaptive management experiments on the hydrosystem. 65 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Chapter 4 Annual SAR by Study Category, TIR, and D for Snake River Hatchery and Wild Spring/Summer Chinook Salmon and Steelhead: Patterns and Significance This chapter presents smolt-to-adult survival rate (SAR) estimates for the spring/summer Chinook and summer steelhead PIT-tagged smolts analyzed in the CSS. A primary focus of comparisons is between the transported and in-river smolt migrants. Parameters estimated include (i) annual SAR from LGR to GRA (LGR’s adult ladder) by study category (transported smolts [T0 or TX beginning 2006], in-river migrants not detected at a Snake River transportation site [C0], and in-river migrants with at least one detection at a Snake River transportation site [C1]), (ii) TIR (ratio of SAR of transported to SAR of C0 migrants), and (iii) D (ratio of post-Bonneville transported SAR to SAR of C0 migrants). Parameters are estimated for PIT-tagged wild Chinook (1994-2008), hatchery Chinook (1997-2008), and wild and hatchery steelhead (1997-2007). Three series of tables previously placed in report appendices will be made available from the FPC Website at www.fpc.org. These appendices have become voluminous and difficult to use. The data in these tables was placed on the FPC website so that the data could be easily accessed by users. The data can be downloaded in a format amenable to analyses by interested users. These tables include (i) the juvenile migrants reach survival rates, (ii) adult return composition, and (iii) numbers of smolts in the CSS study categories. Data for (i) to (iii) are accessed as follows: (i) On FPC homepage, click on “SURVIVAL DATA => JUVENILES => CSS REACH SURVIVAL DATA” to access the individual reach survival estimates used to expand PIT-tag smolt counts in the three study categories to LGR equivalents for each migration year (note: 2006 to be updated and data for 2007 to 2009 added during review period). (ii) On FPC homepage, click on “SURVIVAL DATA => SMOLT-TOADULT => CSS RETURNING ADULT AGE COMPOSITION” to access the number of 1-salt and older returning adults for each PIT-tagged CSS group (note: 2006 to be updated and returns for smolt migration years 2007 [Chinook and steelhead] and 2008 [Chinook only] to be added during review period). (iii) On FPC homepage, click on “SURVIVAL DATA => SMOLT-TOADULT => NUMBER OF SMOLTS AND RETURNING ADULTS BY CSS STUDY CATEGORY” to access the estimated number of smolts and returning adults in each study category (T0 or TX beginning 2006, C0, and C1), and the estimated population of tagged fish arriving LGR, along with a bootstrapped 90% confidence interval around each estimate (note: 2006 to be updated and 2007 [Chinook and steelhead] and 2008 [Chinook only] to be added during review period). 66 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Methods Estimation of smolt numbers in study categories Comparisons between SARs for groups of smolts with different hydrosystem experiences are made from a common start and end point. Thus, LGR-to-GRA SARs were estimated for all groups of smolts including those not detected at LGR as juveniles. The population of PIT-tagged study fish arriving at LGR was partitioned into three pathways related to the route of subsequent passage through the hydrosystem. Fish were “destined” to 1) pass in-river through the Snake River collector dams in a non-bypass channel route (spillways or turbines), 2) pass in-river through the dam’s bypass channel, or 3) pass in a truck or barge to below BON. These three routes of hydrosystem passage defined the study categories C0, C1 and T0 (or TX beginning 2006), respectively. The Snake River basin fish used in SAR estimation were PIT-tagged and released in tributaries and mainstem locations upstream from LGR reservoir. Other investigators (Sanford and Smith 2002; Paulsen and Fisher 2005; Budy and Schaller 2007) have used detection information from smolts released both above LGR and at LGR for their estimates of SARs. Because all Snake River spring/summer Chinook must pass through LGR reservoir, we believe that smolts released upstream from LGR most closely reflect the impacts of the Lower Snake and Columbia River hydrosystem on the untagged runat-large in-river migrating fish. The C0 group may only include smolts released above LGR, since it is defined as those fish that remained in-river while migrating past the three Snake River collector dams undetected. Fish collected and marked at LGR do not have a similar experience. Additionally, the documented bias in SARs (i.e., reduction in estimated survival rates) for groups marked at LGR is another reason for only using PITtagged fish released upstream of LGR in SAR calculations for this analysis. Pre-2006 migration years The PIT-tagged study groups should mimic the experience of the non-tagged fish that they represent. For migration years prior to 2006, only first-time detected tagged smolts at a dam are considered for inclusion in the transportation (T0) group since nontagged smolts were nearly always transported when they entered a bypass/collector facility (where PIT-tag detectors are in operation) at a Snake River dam. Prior to 2006, smolts that were returned to river at LGR, LGS, and LMN were primarily PIT tagged study fish. Typically during these years, most of the transported smolts were from LGR with the remainders be transported from LGS and LMN. Because some smolts died while migrating in-river from LGR to either LGS or LMN, the numbers transported at LGS and LMN were divided by their survival from LGR to transportation site. Therefore, an estimated survival rate was needed to convert actual transport numbers at LGS and LMN into their LGR equivalents starting number. The PIT-tagged fish destined for transportation at LGR, LGS, and LMN together formed Category T0. Using the definitions presented in the following text box, the formula for estimating the number of fish in Category T0 is: 67 1 T0 X 12 X 102 X 1002 S2 S 2 S3 [4.1] Symbol Definitions: R1 = number of PIT-tagged fish released X12 = number of smolts transported at LGR X102 = number of first-detected smolts transported at LGS X112 = number of LGR bypassed smolts transported at LGS X1002 = number of first-detected smolts transported at LMN X1102 = number of LGR bypassed smolts transported at LMN X1012 = number of LGS bypassed smolts transported at LMN X1112 = number of both LGR and LGS bypassed smolts transported at LMN S1 = estimated survival from hatchery release site to LGR tailrace S2 = estimated survival from LGR tailrace to LGS tailrace S3 = estimated survival from LGS tailrace to LMN tailrace S4 = estimated survival from LMN tailrace to MCN tailrace S3 = estimated survival from MCN tailrace to JDA tailrace S3 = estimated survival from JDA tailrace to BON tailrace P2 = estimated detection probability at LGR P3 = estimated detection probability at LGS P4 = estimated detection probability at LMN P5 = estimated detection probability at MCN P6 = estimated detection probability at JDA P7 = estimated detection probability at BON m12 = number of fish first detected at LGR m13 = number of fish first detected at LGS m14 = number of fish first detected at LMN d2 = number of fish removed at LGR (includes all transported fish, site-specific mortalities, unknown disposition fish, and fish removed for use by other research studies) d3 = number of fish removed at LGS (includes all transported fish, site-specific mortalities, and unknown disposition fish) d4 = number of fish removed at LMN (includes all transported fish, site-specific mortalities, unknown disposition fish, and fish removed for use by other research studies) d0 = site-specific removals at dams below LMN of fish not detected previously at a Snake River Dam estimated in LGR-equivalents. Pre-2003 uses fixed expansion rate of 50% survival rate for all removals below LMN. Beginning with migration year 2003, d0 contains site-specific removals below that have been expanded by their corresponding estimated survival rate from LGR. d5.0 = removals of C0 type fish at MCN d6.0 = removals of C0 type fish at JDA d7.0 = removals of C0 type fish at BON d1 = site-specific removals at dams below LMN of fish previously detected at a Snake River Dam estimated in LGR-equivalents. Pre-2003 uses fixed expansion rate of 50% survival rate for all removals below LMN. Beginning with migration year 2003, d1 contains site-specific removals below that have been expanded by their corresponding estimated survival rate from LGR. d5.1 = removals of C1 type fish at MCN d6.1 = removals of C1 type fish at JDA d7.1 = removals of C1 type fish at BON 68 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 The PIT-tagged smolts that passed all Snake River dams undetected (C0) were the group most representative of the non-tagged smolts that migrated in-river during the years prior to 2006, since the C0 group never entered collection facilities at collector dams. Detected PIT-tagged smolts were not representative because they do enter these facilities, and because non-tagged fish that entered a detection/collection facility were normally removed for transportation. The starting number of C0 fish was also computed in LGR equivalents, and therefore required estimates of survival. To estimate the number of smolts that were not detected at any of the collector projects (C0), the number of smolts first detected (transported and non-transported) at LGR, LGS, and LMN (in LGR equivalents) was subtracted from the total number of smolts estimated to arrive at LGR. The number of smolts arriving at LGR was estimated by multiplying the release to LGR survival rate (S1) and release number (R1) (or equivalently, dividing the number of smolts detected at LGR [m12] by the CJS estimate of seasonal LGR detection probability p2) specific for the smolt group of interest. Smolts detected at MCN, JDA, and BON were not excluded from the C0 group since fish entering the bypass facilities at these projects, both tagged and untagged, were generally returned to the river. However, any removal of fish at sites below LMN had to be taken into account. Using symbols defined in the text box, the formula for estimating the number of fish in Category C0 is: m m14 C0 R * S1 m12 13 d0 S S S * 2 2 3 where, for migration years 1994-2002, (d d 6.0 d 7.0 ) d 0 5.0 0.5 and beginning in 2003, d5.0 d 6.0 d 7.0 d0 S 2 * S3 * S 4 S 2 * S3 * S 4 * S5 S 2 * S3 * S 4 * S 5 * S 6 [4.2] . The last group of interest was comprised of fish that were detected at one or more Snake River dams and remained in-river below LMN. These PIT-tagged fish formed Category C1. Prior to 2006, the C1 category existed primarily because a portion of the PIT-tagged smolts entering the detection/collection facility are returned to the river so reach survival estimates are possible. Although these fish do not mimic the general untagged population, they are of interest with regards to possible effects on subsequent survival of passing through Snake River dam bypass/collection systems (see Chapter 7), and in investigating non-transport operations. Using symbols defined in the text box, the formula for estimating the number of fish in Category C1 is: (m d ) (m d 4 ) C1 m12 d 2 13 3 14 d1 S2 S 2 * S3 69 [4.3] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 where, for migration years 1994-2002, (d d d ) d1 5.1 6.1 7.1 0.5 and, beginning in 2003, d5.1 d 6.1 d 7.1 d1 S 2 * S3 * S 4 S 2 * S3 * S 4 * S5 S 2 * S3 * S 4 * S5 * S 6 . A combination of exceptionally low in-river survival and no-spill hydrosystem operations maximized the transportation of smolts in 2001 and resulted in very few estimated Category C0 migrants. Furthermore, the C0 smolts that did exist passed mostly through turbines without the opportunity to pass via spill as in prior years. Obtaining a valid estimate of the number of PIT-tagged wild and hatchery steelhead in Category C0 in 2001 was also problematic due to the apparently large amount of residualism that year (Berggren et al. 2005a). Most in-river steelhead migrants that returned as adults were actually detected as smolts in the lower river in 2002 (details in CSS 10-yr Retrospective Analysis Report). Returning adults of steelhead and Chinook that had no detections were more likely to have either completed their smolt migration in 2002 or passed undetected into the raceways during a computer outage in mid-May at LGR than to have traversed the entire hydrosystem undetected in 2001. Because of the uncertainty in passage route and the timing of the undetected PIT-tagged migrants in 2001, the C1 group was the only viable in-river group for estimation purposes. Due to these conditions, C1 data were used instead of C0 data in the computation of SAR, TIR, and D parameters (described below) and therefore are presented separately for comparison to other years in the multi-year geometric averages computed for SR, TIR, and D. The C0 and C1 groups were combined in two additional migration years. Spills were lower in migration years 2004 and 2005 than previous years at both LGR and LGS (excluding 2001), resulting in high collection efficiency at those two dams and a lower than usual percentage of PIT-tagged smolts estimated to pass the three collector dams on the Snake River undetected (C0 migrants). In 2004, >6% of the LGR population of wild and hatchery Chinook PIT-tagged smolts were in Category C0. Only 2.3% of the hatchery steelhead and 2.6% of the wild steelhead were in Category C0. In 2005, 4.0% of the wild Chinook LGR population, 4.9 – 7.9% of the five CSS hatchery Chinook groups, 1.8% of the hatchery steelhead, and 1.4% of the wild steelhead were in the CO category. When the estimated number of C0 PIT-tagged smolts is extremely low, attempting to estimate SAR(C0) is problematic since few or no adult returns will result in unreliable SAR estimates with large confidence intervals. Therefore, we combined the estimated C0 and C1 smolt numbers for PIT-tagged steelhead in 2004 and both Chinook and steelhead in 2005 in order to create a larger in-river group for estimating SARs, TIR, and D. Migration years 2006 and later In 2006, the protocol for transportation operations was altered by delaying the start date of transportation at LGR, LGS, and LMN (see Appendix C for dates). The goal 70 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 of this change in protocol was to improve the overall SARs by allowing more early runat-large migrants to outmigrate entirely in-river when transport SARs have tended to low (NOAA 2008). Additionally, spill percentages at the Snake River transportation projects during 2006-2008 were consistently higher than many previous years (see Figure 1.4). Also in 2006 the CSS began randomly pre-assigning PIT-tagged wild and hatchery Chinook and wild steelhead smolts into monitor-mode (Group T) and return-toriver mode (Group R) operations. In this chapter, the total release, which is the combination of T and R groups, is designated as Group CRT. Group T follows the same fate as the run at large through-out the hydrosystem, while Group R followed a default return to river action at the transportation dams. With a delayed transportation initiation during these years, two new smolt experiences are developed. First, in regards to the transportation study group, the combination of both first-time detected (T0) and priordetected transported smolts obtained from Group T represent the transported fish from the run at large (referred to as TX). Additionally, the transported fish (TX) only occur over a particular temporal window of the smolt outmigration. The portion of the run that this window includes depends on the intersection of the start date of transportation and timing for the run at large from a particular study group (e.g. Dworshak hatchery Chinook, or wild Snake River steelhead). Secondly, the C1 group (detected and returned to river) now represents the portion of the run at large that out-migrates before transportation started whereas in years before 2006, this group represented a very small portion of the actual run at large (see discussion of C1 group in previous section). One advantage of the pre-assignment approach, when calculating an overall SAR, is that these relationships are automatically encapsulated and proper weighted within Group T since they “follow the fate” of the run at large. Pre-assignment of the PIT-tagged hatchery steelhead began in 2008, so methods described in previous section applies to the 2006 and 2007 PIT-tagged hatchery steelhead aggregate. Parameters may have suffixes of “t”, “r”, or “crt” for groups T, R, and CRT attached whenever necessary to avoid confusion on which group is being used to create the parameter estimate. The formula for estimating the number of PIT-tagged smolts in Group T in Category TX is: TX_t = X12 + X1A2 / S2 + X1AA2 / (S2*S3) [4.4] where A = 0 if undetected and 1 if detected at a dam prior to the transportation site. Since the reach survival rates and collection probabilities are computed using Group CRT, we may still use Equation 4.2 for estimating number of PIT-tagged smolts in Category C0. It is not necessary to limit our use to Group T fish when estimating C0, since the pre-assignment affects only the passage routes of detected smolts. By using Group CRT, we have access to more PIT-tagged C0 smolts and returning adults for computing the SAR(C0) estimate. C0_crt = “see Equation 4.2” However, when estimating C0 or C1 smolt numbers in either Group T or Group R, expectation equations should be used. This is because the computation of C0 and C1 smolt numbers with the m-matrix parameters m12, m13, and m14 is sensitive to the estimated reach survival rates being used. Reach survival rates are estimated using 71 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 Group CRT. Groups T and R are subsets of Group CRT. The magnitudes of m12, m13, and m14 relative to the release number R1 may vary slightly across groups T and R due to sampling variability, resulting in shifts in the proportion of C0 and C1 smolts estimated for each of the two groups. This is not the case when E[C0] and E[C1] equations (shown below) are used, since the same set of reach survival rates and collection probabilities generated with Group CRT are passed to groups T and R for use in estimating key study parameters. Since the random pre-assignment action (bypass or transport) occurs after collection, the same collection probability should apply to both groups and survival estimates should be applicable to either group while it is in-river. The reach survival rates Sj's and collection probabilities Pj's computed with Group CRT are passed to Groups T and R, while the parameters R1, X12, X1A2, X1AA2, and C1 removals (d1, d2, d3, d4) and C0 removals (d0) are specific to the respective group. Therefore, when estimating the proportion of Group T smolts by passage experience as in Appendix C or comparing SARs of C1 smolts bypassed over the entire season (Group R) with C0 smolts (Group CRT) as in the meta analysis of Chapter 7, we use the following expectation formulas. For estimating the expected C0 smolt numbers E[C0]_t and E[C0]_crt, where known removal d0 is a constant, the equation is: where E[C0] = R1•S1•(1-P2)•(1-P3)•(1-P4) – d0 [4.5] d5.0 d 6.0 d 7.0 d0 S 2 * S3 * S 4 S 2 * S3 * S 4 * S5 S 2 * S3 * S 4 * S 5 * S 6 For estimating the expected C1 smolt numbers E(C1)_t and E(C1)_r, where known removals d1, d2, d3, and d4 are constants, the equation is obtained by re-arranging terms in Equation 4.3, where C1 = [m12 + m13/S2 + m14/(S2•S3)] – [d2 + d3/S2 + d4/(S2•S3) + d1] d5.1 d 6.1 d 7.1 d1 S 2 * S3 * S 4 S 2 * S3 * S 4 * S5 S 2 * S3 * S 4 * S5 * S 6 and substituting the following expectations for m12, m13, and m14 to yield: E[m12] = R1•S1•P2 E[m12] = R1•S1•[(1-P2)•S2•P3] E[m12] = R1•S1•[(1-P2)•S2•(1-P3)•S3•P4] E[C1] = R1•S1•[P2 + (1-P2)•P3 + (1-P2)•(1-P3)•P4] – [(d2 + d3/S2 + d4/(S2•S3) + d1] Estimation of SARs and Ratios of SARs for Study Categories [4.6] LGR is the primary upriver evaluation site for most objectives of the CSS. Adults detected at GRA (LGR’s adult ladder) were assigned to a particular study category based 72 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 on the study category they belonged to as a smolt (fish with no previous detections at any dam were automatically assigned to Category C0). In the SAR estimation, the adult steelhead count is the sum of the 1 to 3-ocean returns (mini-jacks returning in the same year as their smolt outmigration are excluded). The adult Chinook count is the sum of the 2 to 4-ocean returns. Chinook jacks and mini-jacks (1-ocean or less, precocious males) are excluded from SARs due to the limited contribution to spawning of these age classes. SARs are calculated by study category with the adult tally in the numerator and estimated smolt numbers in denominator. Prior to 2006 (2008 for hatchery steelhead) when there was no pre-assignment of CSS study fish to Groups T and R, the formulas are: SAR T0 ATLGR ATLGS ATLMN SAR C0 SAR C1 [4.7] AC0 C0 AC1 C1 [4.8] [4.9] For migration years 2006 and later, the adult counts (i.e. ATLGR, ATLGS, ATLMN) include both first time detects and previous detected fish. The abbreviated capture histories for the smolt outmigration experience of adults from the TX group (using a ‘1’ for a single release followed by a 1,0, or 2 to denote bypass, undetected, or transported at LGR, LGS, or LMN) would be 12, 102, 1002, 12, 102, 112, 1002, 1012, 1102, or 1112. Using the pre-assigned fish in Group T, the equation for SAR(TX_t) is: SAR(TX_t) = {ATLGR_t + ATLGS_t + ATLMN_t } / TX_t [4.10] Using the total release, the formula for SAR(C0_crt) is: SAR(C0_crt) = {AC0_crt} / C0_crt [4.11] Using the pre-assigned fish in Group T, the equations for SAR[EC1_t] is: SAR[EC1_t] = {AC1_t} / E[C1_t] [4.12] The difference between SAR(T0) (or SAR(TX_t) beginning 2006) and SAR(C0) is characterized as the ratio of these SARs and denoted as the TIR (transport: in-river ratio): TIR 39 T0 SAR T0 SAR C0 73 [4.13] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 The statistical test of whether SAR(T0) (or SAR(TX_t) beginning 2006) is significantly different than SAR(C0) is conducted by evaluating whether TIR differs from one. We use the criteria that the non-parametric 90% confidence interval’s lower limit of TIR must exceed 1 or its upper limit must be less than 1. This provides a statistical twotailed (α=0.10) test of H0 TIR = 1 versus HA TIR ≠1. Estimation of D The parameter used to evaluate the differential delayed effects of transportation in relation to in-river outmigrants is D. D is the ratio of SARs of transported smolts (T0) and in-river outmigrants (C0), but unlike TIR, the SAR is estimated from BON instead of from LGR. If the value of D is around 1, there is little or no differential mortality occurring between transported and in-river migrating smolts once they are both below BON. The estimate of D (substituting TX for T0 for migration years 2006 and later) is: D 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 SARBON LGR T0 SARBON LGR C0 [4.14] The total number of smolts passing BON is not observed directly. However, D can be estimated by removing the portion of the LGR-to-GRA SAR that contains the LGR to BON juvenile hydrosystem survival. So, the parameters ST and SR were divided out of their respective LGR-to-GRA SAR values to estimate the SARBON-LGR for each study group shown in Equation 4.14. The resulting estimate of D (substituting TX for T0 for migration years 2006 and later) was calculated as: SAR T0 ST D SAR C0 SR [4.15] where SR is the estimated in-river survival from LGR tailrace to BON tailrace and ST is the assumed direct transportation survival rate (0.98) adjusted for in-river survival to the respective transportation sites for those fish transported from LGS or LMN. In the denominator of D (in-river portion), the quotient is simply SAR(C0)/ SR, where SR is estimated using CJS estimates (expanded to the entire hydro system if necessary). Errors in estimates of SR influenced the accuracy of D estimates: recall that when it was not possible to estimate SR directly, an expansion based on a “per mile” survival rate obtained from an upstream reach (where survival could be directly estimated) was instead applied to the remaining downstream reach. In the numerator of D (transportation portion), the quotient is SAR(T0)/ST, where ST is a weighted harmonic mean estimate of the in-river survival rate between LGR tailrace and downstream Snake River transportation sites for the estimated projectspecific proportion of the transported run-at-large at these two downstream transportation 74 1 2 3 4 5 sites. Calculation of ST includes an estimate of survival to each transportation site, effectively putting ST into LGR equivalents similar to SAR(T0), with a fixed 98% survival rate for the fish once they were placed into the transportation vehicle (truck or barge). The ST estimate for years prior to 2006 is: ST 0.98 * 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 t 2 t3 t 4 t3 t4 t2 S 2 S 2 * S3 [4.16] where tj is the estimate of the fraction of PIT-tagged fish that would have been transported at each dam (e.g., t2 = LGR, t3 = LGS, and t4 = LMN) if all PIT-tagged fish had been routed to transport at the same rate as the run-at-large (i.e., untagged fish). Beginning in 2006 with pre-assignment to Group T for all PIT-tagged fish groups except hatchery steelhead, the values for tj were obtained directly using Group T for the number of PIT-tagged smolts (X) with the following capture histories (shown in subscript): t2 = X12, t3 = X1A2, and t4 = X1AA2. Since the routing of the PIT-tagged hatchery steelhead was in the same proportion at each collector dam, the values for tj were obtained directly with the total release for the above capture histories. Using this approach for all PIT-tagged groups properly accounted for the effect of the later start of transportation in years beginning in 2006. The ST estimate for years 2006 and later is: ST = (0.98)[(X12+X1A2+ X1AA2)/(X12+X1A2/S2+ X1AA2/(S2•S3)] [4.17] The estimates of ST have ranged between 0.88 and 0.98 for Chinook and steelhead across all the years evaluated. A statistical test of whether D is significantly greater or less than 1 was conducted in the same manner as was done with TIR. We use the criteria that the non-parametric 90% confidence interval’s lower limit of D must exceed 1 or its upper limit must be less than 1. This provides a statistical two-tailed (α=0.10) test of H0 D = 1 versus HA D ≠1. 75 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Results Estimates of SAR by Study Category Wild and hatchery Chinook The PIT-tagged wild Chinook aggregate LGR-to-GRA SAR estimates by study category over the 15-year time span from 1994 to 2008 have exceeded 2% in only 4 years for C0 fish, 2 years for T0 (or TX beginning 2006) fish, and 1 year for C1 fish (Figure 4.1 and Table 4.1). Therefore, wild Chinook SARs have remained far below those recommended to maintain a stable population (2%) or to achieve recovery (4%; Marmorek et al. 1998) over this 15-year period. The estimated SARs were exceptionally low (< 0.6%) during the two periods 1994 to 1996 and 2003 to 2005 in all three categories and also in 2001 for in-river migrants. On a positive note, the trend in SARs since 2005 has been increasing, with the available 2-salt return of the 2008 migrants approaching the highs not seen since 1999 and 2000. Figure 4.1 Estimated LGR-to-GRA SAR for PIT-tagged wild Chinook aggregate in transport (T0 or TX beginning 2006) and in-river (C0 and C1) study categories for migration years 1994 to 2008 (incomplete adult returns for 2008). The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date (shaded area). For 2001 and 2005, only 1 in-river SAR was calculated (see methods). Data from Table 4.1. 76 1 Table 4.1 Estimated LGR-to-GRA SAR (%) for PIT-tagged wild Chinook in annual aggregate for each study category from 1994 to 2008 (with 90% confidence intervals). The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date. Mig. Year 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 Monitormode yrsB SAR(T0) % 0.45 0.35 0.50 1.74 1.18 2.43 1.43 1.28 0.80 0.34 0.53 0.23 (0.20 – 0.72) (0.17 – 0.57) (0.00 – 1.07) (0.44 – 3.27) (0.71 – 1.70) (1.85 – 3.07) (0.74 – 2.14) (0.54 – 2.14) (0.57 – 1.04) (0.24 – 0.45) (0.42 – 0.63) (0.17 – 0.29) SAR(TX)_t % SAR(C0) % 0.28 (0.11 – 0.51) 0.37 (0.18 – 0.57) 0.26 (0.10 – 0.48) 2.35 (1.45 – 3.36) 1.36 (1.05 – 1.70) 2.13 (1.78 – 2.50) 2.39 (2.08 – 2.72) Assume = SAR(C1) 1.22 (0.99 – 1.45) 0.33 (0.23 – 0.43) 0.49 (0.26 – 0.74) 0.11 A SAR(C0)_crt % SAR(C1) % 0.07 0.25 0.13 0.93 1.07 1.89 2.33 0.14 0.99 0.17 0.22 (0.07 – 0.15) (0.02 – 0.14) (0.18 – 0.32) (0.06 – 0.23) (0.60 – 1.32) (0.91 – 1.22) (1.76 – 2.04) (2.12 – 2.52) (0.10 – 0.18) (0.84 – 1.14) (0.12 – 0.23) (0.16 – 0.29) SAR(EC1)_t % 2006 0.76 (0.60 – 0.90) 0.97 (0.71 – 1.26) 0.36 (0.18 – 0.56) 2007 C 1.20 (x.xx – x.xx) 0.94 (x.xx – x.xx) 0.88 (x.xx – x.xx) 2008 C 2.17 (x.xx – x.xx) 2.22 (x.xx – x.xx) 2.48 (x.xx – x.xx) 15-yr avg. 1.01 (0.69 – 1.33) 1.03 (0.63 – 1.42) 0. 80 (0.42 – 1.18) A In-river SAR is combination of groups C0 and C1 B Estimated SARs for TX and C1 with Group T, and C0 with combined Group CRT C Complete 3-salt for 2007 and 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Estimated SARs among the hatchery Chinook populations exhibit variation among years, among hatcheries, and among outmigration categories (Figure 4.2 and Tables 4.2 to 4.6). However, the inter-annual patterns of variation are generally similar among hatcheries and between hatchery groups in the aggregate and wild Chinook for each of the outmigration categories. Within the in-river study categories (C1 and C0), the wild Chinook often did as well as or better than most hatchery groups (top and middle panels Figure 4.2). However the wild transported SAR was often below the top of the hatcheries’ transportation SARs. The exceptions are 2007 and 2008 (when transportation was delayed until May 1st) where the wild transportation SARs were higher than 4 of the 5 hatcheries’ transportation SARs. These are the only years where this occurred and may imply a benefit in the changed transportation protocol for wild Chinook. Among the hatchery groups, the Catherine Creek group displayed a marked increase in transportation SAR during 2008. The estimated SARs of the PIT-tagged in-river migrants (C0 and C1) from McCall Hatchery were generally in the same range as their PIT-tagged wild Chinook counterparts (Figure 4.2 top and middle panel), while the SARs of transported McCall Hatchery Chinook were generally higher than that of both the wild and remaining hatchery groups (Figure 4.2 lower panel). Dworshak Hatchery Chinook consistently exhibited lower SARs for transported smolts than did wild or other hatchery groups. In general, the two hatchery summer Chinook populations had higher SARs than the hatchery spring Chinook populations. 77 1 2 3 4 5 6 7 Figure 4.2 Estimated LGR-to-GRA SAR for PIT-tagged wild Chinook aggregate and five CSS hatchery groups in transport (T0 or TX beginning 2006) and in-river (C0 and C1) study categories for migration years 1994 to 2008 (incomplete adult returns for 2008). The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date (shaded area). For 2001 and 2005, only 1 in-river SAR was calculated (see methods). Data from Tables 4.2–6. 78 Table 4.2 Estimated LGR-to-GRA SAR (%) for PIT-tagged spring Chinook from Rapid River Hatchery for each study category from 1997 to 2008 (with 90% confidence intervals). The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date. Mig. Year 1997 1998 1999 2000 2001 2002 2003 2004 2005 Monitormode yrsB SAR(T0) % 0.79 2.00 3.04 2.10 1.08 1.01 0.25 0.36 0.27 (0.57 – 1.01) (1.80 – 2.21) (2.78 – 3.31) (1.91 – 2.28) (0.96 – 1.21) (0.86 – 1.16) (0.18 – 0.32) (0.29 – 0.43) (0.21 – 0.34) SAR(TX)_t % SAR(C0) % 0.45 (0.31 – 0.63) 1.20 (0.95 – 1.48) 2.37 (2.07 – 2.68) 1.59 (1.40 – 1.81) {Assume =SAR(C1)} 0.67 (0.55 – 0.79) 0.23 (0.17 – 0.29) 0.23 (0.11 – 0.39) 0.12 A SAR(C0)_crt % SAR(C1) % 0.53 0.67 1.63 1.33 0.05 0.63 0.15 0.12 (0.07 – 0.16) (0.39 – 0.68) (0.56 – 0.79) (1.46 – 1.79) (1.07 – 1.58) (0.02 – 0.08) (0.53 – 0.74) (0.08 – 0.24) (0.07 – 0.16) SAR(EC1)_t % 2006 0.57 (0.48– 0.66) 0.42 (0.30 – 0.54) 0.19 (0.05 – 0.35) 2007 0.45 (0.33 – 0.56) 0.25 (0.19 – 0.31) 0.38 (0.22 – 0.56) 2008 C 1.39 (x.xx – x.xx) 0.90 (x.xx – x.xx) 1.11 (x.xx – x.xx) 12-yr avg. 1.11 (0.66 – 1.56) 0.71 (0.34 – 1.07) 0.58 (0.30 – 0.85) A In-river SAR is combination of groups C0 and C1 B Estimated SARs for TX and C1 with Group T, and C0 with combined Group CRT C Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) 1 Table 4.3 Estimated LGR-to-GRA SAR (%) for PIT-tagged spring Chinook from Dworshak Hatchery for each study category from 1997 to 2008 (with 90% confidence intervals). The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date. Mig. Year 1997 1998 1999 2000 2001 2002 2003 2004 2005 Monitormode yrsB 2 SAR(T0) % 0.83 0.90 1.18 1.00 0.36 0.62 0.26 0.28 0.20 (0.52 – 1.19) (0.77 – 1.02) (1.01 – 1.35) (0.88 – 1.12) (0.29 – 0.43) (0.49 – 0.75) (0.19 – 0.33) (0.23 – 0.35) (0.16 – 0.26) SAR(TX)_t % SAR(C0) % SAR(C1) % 0.47 (0.26 – 0.72) 0.36 1.25 (1.08 – 1.42) 0.90 1.19 (1.01 – 1.37) 0.95 1.01 (0.87 – 1.16) 0.81 {Assume =SAR(C1)} 0.04 0.50 (0.42 – 0.58) 0.50 0.21 (0.16 – 0.27) 0.18 0.32 (0.21 – 0.44) 0.18 0.14 A (0.10 – 0.19) SAR(C0)_crt % (0.21 – 0.54) (0.77 – 1.04) (0.82 – 1.07) (0.62 – 1.02) (0.02 – 0.07) (0.40 – 0.58) (0.10 – 0.27) (0.13 – 0.25) SAR(EC1)_t % 2006 0.36 (0.29 – 0.44) 0.38 (0.30 – 0.47) 0.19 (0.09 – 0.31) 2007 0.59 (0.35 – 0.86) 0.32 (0.27 – 0.38) 0.29 (0.19 – 0.40) 2008 C 0.75 (x.xx – x.xx) 0.47 (x.xx – x.xx) 0.39 (x.xx – x.xx) 12-yr avg. 0. 61 (0.44 – 0.78) 0. 53 (0.32 – 0.73) 0.41 (0.25 – 0.57) A In-river SAR is combination of groups C0 and C1 B Estimated SARs for TX and C1 with Group T, and C0 with combined Group CRT C Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) 79 1 Table 4.4 Estimated LGR-to-GRA SAR (%) for PIT-tagged spring Chinook from Catherine Creek AP for each study category from 2001 to 2008 (with 90% confidence intervals). The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date. Mig. Year 2001 2002 2003 2004 2005 Monitormode yrsB SAR(T0) % 0.23 0.89 0.36 0.38 0.44 (0.12 – 0.35) (0.59 – 1.20) (0.20 – 0.56) (0.21 – 0.57) (0.24 – 0.65) SAR(TX)_t % SAR(C0) % {Assume =SAR(C1)} 0.49 (0.28 – 0.74) 0.25 (0.10 – 0.41) 0.20 (0.00 – 0.60) 0.18 A SAR(C0)_crt % SAR(C1) % 0.04 0.32 0.35 0.32 (0.04 – 0.35) (0.00 – 0.09) (0.18 – 0.50) (0.14 – 0.61) (0.11 – 0.54) SAR(EC1)_t % 2006 0.45 (0.24 – 0.67) 0.93 (0.55 – 1.33) -0- C 2007 0.50 (0.27 – 0.76) 0.37 (0.20 – 0.55) 1.04 (0.25 – 2.40) 2008 D 2.48 (x.xx – x.xx) 1.79 (x.xx – x.xx) 0.85 (x.xx – x.xx) 8-yr avg. 0.78 (0.17 – 1.39) 0.53 (0.15 – 0.92) 0.39 (0.14 – 0.64) A In-river SAR is combination of groups C0 and C1 B Estimated SARs for TX and C1 with Group T, and C0 with combined Group CRT C Only 274 PIT-tagged Catherine Creek hatchery Chinook estimated in C1 category with no adult returns – the 8-yr average includes this zero value. D Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) 2 3 Table 4.5 Estimated LGR-to-GRA SAR (%) for PIT-tagged summer Chinook from McCall Hatchery for each study category from 1997 to 2008 (with 90% confidence intervals). The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date. Mig. Year 1997 1998 1999 2000 2001 2002 2003 2004 2005 Monitormode yrsB SAR(T0) % 1.51 2.69 3.59 3.88 1.24 1.48 0.79 0.40 0.62 (1.26 – 1.77) (2.44 – 2.96) (3.29 – 3.87) (3.60 – 4.18) (1.10 – 1.38) (1.27 – 1.70) (0.68 – 0.92) (0.34 – 0.48) (0.54 – 0.71) SAR(TX)_t % SAR(C0) % SAR(C1) % 1.09 (0.88 – 1.34) 1.10 1.38 (1.05 – 1.69) 0.73 2.40 (2.12 – 2.69) 2.03 2.06 (1.84 – 2.29) 2.03 {Assume =SAR(C1)} 0.04 1.03 (0.87 – 1.20) 1.02 0.54 (0.45 – 0.62) 0.34 0.25 (0.09 – 0.44) 0.12 0.20 A (0.16 – 0.26) SAR(C0)_crt % (0.92 – 1.29) (0.62 – 0.87) (1.82 – 2.26) (1.68 – 2.38) (0.01 – 0.07) (0.89 – 1.18) (0.24 – 0.46) (0.07 – 0.16) SAR(EC1)_t % 2006 1.15 (1.01 – 1.30) 1.04 (0.85 – 1.22) 0.77 (0.42 – 1.20) 2007 1.46 (1.18 – 1.74) 0.71 (0.60 – 0.81) 0.57 (0.31 – 0.86) 2008 C 1.22 (x.xx – x.xx) 0.77 (x.xx – x.xx) 0.80 (x.xx – x.xx) 12-yr avg. 1.67 (1.09 – 2.25) 0. 96 (0.59 – 1.33) 0.81 (0.47 – 1.16) A In-river SAR is combination of groups C0 and C1 B Estimated SARs for TX and C1 with Group T, and C0 with combined Group CRT C Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) 4 80 1 Table 4.6 Estimated LGR-to-GRA SAR (%) for PIT-tagged summer Chinook from Imnaha River AP for each study category from 1997 to 2008 (with 90% confidence intervals). The transport SAR (TX) after 2005 is a partial year metric because of the delay in transportation start date. Mig. Year 1997 1998 1999 2000 2001 2002 2003 2004 2005 Monitormode yrsB SAR(T0) % 1.16 0.85 2.69 3.11 0.62 0.79 0.58 0.38 0.28 (0.77 – 1.60) (0.65 – 1.09) (2.28 – 3.08) (2.77 – 3.44) (0.49 – 0.78) (0.56 – 1.04) (0.40 – 0.75) (0.26 – 0.49) (0.18 – 0.40) SAR(TX)_t % SAR(C0) % SAR(C1) % 0.86 (0.53 – 1.22) 0.69 0.55 (0.28 – 0.83) 0.30 1.43 (1.08 – 1.82) 1.22 2.41 (2.01 – 2.83) 1.64 {Assume =SAR(C1)} 0.06 0.45 (0.29 – 0.63) 0.55 0.48 (0.34 – 0.62) 0.38 0.23 (0.07 – 0.48) 0.11 0.16 A (0.08 – 0.26) SAR(C0)_crt % (0.48 – 0.93) (0.20 – 0.42) (0.98 – 1.49) (1.22 – 2.08) (0.01 – 0.11) (0.38 – 0.72) (0.20 – 0.59) (0.04 – 0.20) SAR(EC1)_t % 2006 0.77 (0.58 – 0.97) 1.25 (0.93 – 1.61) 0.40 (0.10 – 0.77) 2007 1.02 (0.69 – 1.37) 0.63 (0.47 – 0.78) 0.52 (0.27 – 0.78) 2008 C 1.75 (x.xx – x.xx) 1.22 (x.xx – x.xx) 1.80 (x.xx – x.xx) 12-yr avg. 1.17 (0.70 – 1.63) 0.81 (0.46 – 1.16) 0.65 (0.35 – 0.96) A In-river SAR is combination of groups C0 and C1 B Estimated SARs for TX and C1 with Group T, and C0 with combined Group CRT C Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Wild and hatchery Steelhead The PIT-tagged steelhead LGR-to-GRA SAR estimates of transported smolts over the 11-year time span from 1997 to 2007 exceeded 2% in 5 years for the aggregate of wild stocks and in 4 years for the aggregate of hatchery stocks, but with only one year (2000) common to both wild and hatchery PIT-tag groups (Figures 4.3 and 4.4 and Tables 4.7 and 4.8). The SARs for in-river migrants did not exceed 2% in any year for wild and hatchery PIT-tag groups, but the pattern of inter-annual variability for the inriver SARs was similar for hatchery and wild steelhead (Figures 4.3 and 4.4). The sample sizes for wild and hatchery steelhead PIT-tag groups have been small, which results in few adult returns and rather large 90% confidence intervals for the SAR estimates (Tables 4.7 and 4.8). During the first year with a May 1st transportation start date, the wild steelhead transported SAR displayed a marked increase as compared to inriver SARs– the highest in the time series (Figure 4.3). However, in the case of hatchery steelhead, the transportation SAR in 2008 was concurrent with the SAR of in-river groups. 81 1 2 3 4 5 6 7 8 9 Figure 4.3 Estimated LGR-to-GRA SAR for PIT-tagged wild steelhead aggregate in transport (T0 or TX beginning 2006) and in-river (C0 and C1) study categories for migration years 1997 to 2007. The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date (shaded area). For 2001, 2004, and 2005, only 1 in-river SAR was calculated (see methods). Data from Table 4.7. Table 4.7 Estimated LGR-to-GRA SAR (%) for PIT-tagged wild steelhead in annual aggregate for each study category from 1997 to 2007 (with 90% confidence intervals). The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date. Mig. Year 1997 1998 1999 2000 2001 2002 2003 2004 2005 Monitormode yrsB SAR(T0) % 1.45 0.21 3.07 2.79 2.49 2.84 1.99 0.87 0.84 (0.36 – 2.80) (0.0 – 0.63) (1.74 – 4.66) (1.55 – 4.11) (0.93 – 4.37) (1.52 – 4.43) (1.52 – 2.51) (0.65 – 1.11) (0.63 – 1.07) SAR(TX)_t % SAR(C0) % SAR(C1) % 0.66 (0.00 – 1.34) 0.23 1.07 (0.51 – 1.73) 0.21 1.35 (0.80 – 1.96) 0.76 1.92 (1.40 – 2.49) 1.81 {Assume =SAR(C1)} 0.07 0.67 (0.46 – 0.90) 0.94 0.45 (0.27 – 0.66) 0.52 0.06 A (0.02 – 0.11) 0.17 A (0.11 – 0.25) SAR(C0)_crt % (0.10 – 0.39) (0.12 – 0.33) (0.60 – 0.94) (1.59 – 2.03) (0.03 – 0.10) (0.77 – 1.11) (0.37 – 0.66) SAR(EC1)_t % 2006 1.31 (1.02 – 1.66) 1.54 (0.72 – 2.44) 0.60 (0.27 – 0.92) 2007 C 4.18 (3.55 – 4.83) 1.42 (1.09 – 1.72) 1.72 (1.20 – 2.36) 11-yr avg. 2.00 (1.36 – 2.65) 0.85 (0.50 – 1.21) 0.64 (0.30 – 0.99) A In-river SAR is combination of groups C0 and C1 B Estimated SARs for TX and C1 with Group T, and C0 with combined Group CRT C Incomplete steelhead adult returns until 3-salt returns (if any) occur after 7/1/2010 at GRA. 82 1 2 3 4 5 6 7 8 9 Figure 4.4 Estimated LGR-to-GRA SAR for PIT-tagged hatchery steelhead aggregate in transport (T0 or TX beginning 2006) and in-river (C0 and C1) study categories for migration years 1997 to 2007. The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date (shaded area). For 2001, 2004, and 2005, only 1 in-river SAR was calculated (see methods). Data from Table 4.8. Table 4.8 Estimated LGR-to-GRA SAR (%) for PIT-tagged hatchery steelhead in annual aggregate for each study category from 1997 to 2007 (with 90% confidence intervals). The transport SAR(TX) after 2005 is a partial year metric because of the delay in transportation start date. Mig. Year SAR(T0) % SAR(C0) % SAR(C1) % 1997 0.52 (0.24 – 0.81) 0.24 (0.09 – 0.39) 0.17 (0.12 – 0.22) 1998 0.51 (0.22 – 0.84) 0.89 (0.61 – 1.19) 0.22 (0.17 – 0.28) 1999 0.90 (0.51 – 1.33) 1.04 (0.79 – 1.31) 0.59 (0.51 – 0.69) 2000 2.10 (1.22 – 3.07) 0.95 (0.71 – 1.19) 1.05 (0.92 – 1.18) 2001 0.94 (0.24 – 1.78) {Assume =SAR(C1)} 0.016 (0.005 – 0.03) 2002 1.06 (0.32 – 2.11) 0.70 (0.54 – 0.88) 0.73 (0.61 – 0.85) 2003 1.81 (1.50 – 2.13) 0.68 (0.52 – 0.86) 0.37 (0.26 – 0.47) 2004 2.13 (1.17 – 3.27) 0.21 A (0.15 – 0.26) 2005 2.03 (1.28 – 2.83) 0.24 A (0.18 – 0.30) B 2006 2.14 (1.49 – 2.84) 1.42 (0.94 – 1.93) 1.23 (1.06 – 1.41) 2007 B C 1.94 (1.51 – 2.38) 1.17 (0.96 – 1.38) 0.92 (0.78 – 1.07) 11-yr avg. 1.46 (1.09 – 1.83) 0.69 (0.44 – 0.94) 0.52 (0.30 – 0.74) A In-river SAR is combination of groups C0 and C1 B No pre-assignment for hatchery steelhead, so one group; transport SARs estimated with TX smolts. C Incomplete steelhead adult returns until 3-salt returns (if any) occur after 7/1/2010 at GRA. 83 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 Estimates of TIR and D Wild and hatchery Chinook The TIR is a measure of the relative performance of transported (T0 or Tx beginning in 2006) and in-river migrating C0 smolts. A TIR > 1.0 indicates that a transported SAR was greater than an in-river SAR while a TIR < 1.0 indicates that a transported SAR was less than an in-river SAR. A TIR is statistically different from 1.0 when its 90% confidence interval does not encompass 1.0 (i.e., a lower limit value >1 or upper limit value <1 of the 90% confidence interval provides a two-tail (α=0.10) test of H0: TIR = 1 versus HA: TIR ≠1). For wild Chinook, the TIR values were greater than one in 8 of the 15 years (Table 4.9). However, the wild Chinook TIRs were not statistically different from 1.0 in most study years. Estimated TIRs varied substantially among hatcheries and across years. For most years, estimated TIRs for Rapid River Hatchery spring Chinook and McCall Hatchery summer Chinook were greater than one with statistical significance (Tables 4.10 and 4.13). Statistical significance in TIRs occurred in very few years for spring Chinook from Dworshak NFH and Catherine Creek AP facility (Tables 4.11 and 4.12). Results were more mixed across years for summer Chinook from Imnaha AP facility (Table 4.14). The pattern of inter-annual variability in TIRs (natural log-transformed) was similar among the PIT-tagged wild and hatchery groups, but the yearly magnitude of the wild Chinook TIRs was generally lower than that of most PIT-tagged hatchery groups (Figure 4.5). Figure 4.5 Trend in TIR on the natural log scale for PIT-tagged Snake river hatchery and wild Chinook for migration years 1994 to 2007. The grey reference line denotes a TIR value of 1 (in-river and transport SARs equal). After 2005, transport operations initiated on a delayed start date 84 1 2 compared to previous years. TIR calculation for 2001 and 2005 differs from other years as in-river SAR component of ratio includes C1 fish (see methods). Data from Tables 4.9–14. 85 1 2 3 Table 4.9 Estimated TIR and D of PIT-tagged wild Chinook for migration years 1994 to 2008 (with 90% confidence intervals). Lower limit values >1 are highlighted in yellow and upper limit values <1 are highlighted in blue. After 2005, transport operations initiated on a delayed start date compared to previous years. Mig. Year TIR D 1994 1.62 (0.62 – 5.05) 0.36 (0.13 – 1.09) 1995 0.95 (0.39 – 2.14) 0.42 (0.17 – 1.09) 1996 1.92 (0.00 – 6.80) 0.92 (0.00 – 3.24) 1997 0.74 (0.17 – 1.58) 0.40 (0.08 – 0.95) 1998 0.87 (0.50 – 1.35) 0.55 (0.31 – 0.87) 1999 1.14 (0.82 – 1.51) 0.72 (0.52 – 0.98) 2000 0.60 (0.32 – 0.92) 0.32 (0.17 – 0.51) 2001D 8.96 (3.61 – 16.8) 2.16 (0.87 – 4.16) 2002 0.65 (0.45 – 0.94) 0.44 (0.29 – 0.68) 2003 1.05 (0.68 – 1.68) 0.68 (0.43 – 1.12) 2004 1.09 (0.68 – 2.19) 0.45 (0.27 – 0.95) 2005 A 2.14 (1.40 – 3.45) 1.07 (0.65 – 1.85) 2006 B 0.78 (0.54 – 1.14) 0.47 (0.31 – 0.75) 2007 B C 1.27 (x.xx – x.xx) 0.80 (x.xx – x.xx) 2008 B C 0.98 (x.xx – x.xx) 0.47 (x.xx – x.xx) Geomean 1.21 (0.90 – 1.64) 0.59 (0.47 – 0.75) A In-river SAR is combination of groups C0 and C1 in derivation of TIR and D. B TIR and D use SAR for TX estimated with Group T and C0 with combined Group CRT. C Complete 3-salt for 2007 and 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) D For migration year 2001, the SAR(C1) value is used in the derivation of TIR and D. Table 4.10 Estimated TIR and D of PIT-tagged Rapid River Hatchery spring Chinook for 1997 to 2008 (with 90% confidence intervals). Lower limit values >1 are highlighted in yellow and upper limit values <1 are highlighted in blue. After 2005, transport operations initiated on a delayed start date compared to previous years. Mig. Year 4 TIR D 1997 1.73 (1.08 – 2.85) 0.61 (0.37 – 1.09) 1998 1.66 (1.32 – 2.16) 1.01 (0.80 – 1.36) 1999 1.28 (1.11 – 1.51) 0.79 (0.65 – 0.99) 2000 1.32 (1.13 – 1.55) 0.82 (0.66 – 1.25) 2001D 21.7 (13.3 – 54.1) 7.33 (4.40 – 16.9) 2002 1.51 (1.20 – 1.91) 1.14 (0.87 – 1.52) 2003 1.07 (0.73 – 1.58) 0.75 (0.50 – 1.15) 2004 1.57 (0.88 – 3.67) 0.57 (0.31 – 1.46) 2005 A 2.36 (1.59 – 3.79) 1.31 (0.83 – 2.30) 2006 B 1.35 (0.98 – 1.91) 0.83 (0.60 – 1.19) 2007 B 1.81 (1.26 – 2.53) 1.20 (0.82 – 1.74) 2008 B C 1.54 (x.xx – x.xx) 0.90 (x.xx – x.xx) Geomean 1.91 (1.27 – 2.88) 1.04 (0.74 – 1.47) A In-river SAR is combination of groups C0 and C1 in derivation of TIR and D. B TIR and D use SAR for TX estimated with Group T and C0 with combined Group CRT. C Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) D For migration year 2001, the SAR(C1) value is used in the derivation of TIR and D. 86 Table 4.11 Estimated TIR and D of PIT-tagged Dworshak Hatchery spring Chinook for 1997 to 2008 (with 90% confidence intervals). Lower limit values >1 are highlighted in yellow and upper limit values <1 are highlighted in blue. After 2005, transport operations initiated on a delayed start date compared to previous years. Mig. Year 1 2 3 TIR D 1997 1.75 (0.92 – 3.46) 0.88 (0.40 – 2.01) 1998 0.72 (0.59 – 0.88) 0.37 (0.30 – 0.47) 1999 0.99 (0.81 – 1.24) 0.60 (0.47 – 0.81) 2000 0.99 (0.82 – 1.19) 0.53 (0.42 – 0.75) 2001D 8.76 (5.04 – 20.4) 2.21 (1.23 – 5.30) 2002 1.24 (0.93 – 1.61) 0.84 (0.61 – 1.12) 2003 1.21 (0.81 – 1.75) 0.88 (0.58 – 1.37) 2004 0.89 (0.59 – 1.43) 0.46 (0.28 – 0.77) 2005 A 1.43 (0.97 – 2.17) 0.77 (0.51 – 1.22) 0.95 (0.69 – 1.30) 0.60 (0.43 – 0.83) 2006 B 2007 B 1.84 (1.11 – 2.81) 1.31 (0.78 – 2.02) 2008 B C 1.58 (x.xx – x.xx) 0.70 (x.xx – x.xx) Geomean 1.40 (1.00 – 1.96) 0.75 (0.59 – 0.96) A In-river SAR is combination of groups C0 and C1 in derivation of TIR and D. B TIR and D use SAR for TX estimated with Group T and C0 with combined Group CRT. C Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) D For migration year 2001, the SAR(C1) value is used in the derivation of TIR and D. Table 4.12 Estimated TIR and D of PIT-tagged Catherine Creek AP spring Chinook for 2001 to 2008 (with 90% confidence intervals). Lower limit values >1 are highlighted in yellow and upper limit values <1 are highlighted in blue. After 2005, transport operations initiated on a delayed start date compared to previous years. Mig. Year 4 TIR D 2001D 5.33 (0.00 – 13.6) 1.38 (0.03 – 3.79) 2002 1.81 (1.02 – 3.43) 1.23 (0.59 – 2.79) 2003 1.45 (0.65 – 3.79) 0.94 (0.41 – 2.53) 2004 1.94 (0.00 – 2.57) 0.95 (0.00 – 1.33) 2005 A 2.48 (1.02 – 10.6) 1.32 (0.50 – 5.90) 2006 B 0.48 (0.25 – 0.88) 0.26 (0.13 – 0.50) 2007 B 1.35 (0.65 – 2.71) 1.02 (0.46 – 2.29) 2008 B C 1.38 (x.xx – x.xx) 0.70 (x.xx – x.xx) 1.67 (1.09 – 2.56) 0.88 (0.63 – 1.24) Geomean A In-river SAR is combination of groups C0 and C1 in derivation of TIR and D. B TIR and D use SAR for TX estimated with Group T and C0 with combined Group CRT. C Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) D For migration year 2001, the SAR(C1) value is used in the derivation of TIR and D. 87 1 Table 4.13 Estimated TIR, and D of PIT-tagged McCall Hatchery summer Chinook for 1997 to 2008 (with 90% confidence intervals). Lower limit values >1 are highlighted in yellow and upper limit values <1 are highlighted in blue. After 2005, transport operations initiated on a delayed start date compared to previous years. Mig. Year 2 3 TIR D 1997 1.38 (1.06 – 1.80) 0.64 (0.43 – 0.93) 1998 1.96 (1.54 – 2.56) 1.16 (0.89 – 1.54) 1999 1.49 (1.29 – 1.73) 0.87 (0.72 – 1.07) 2000 1.89 (1.67 – 2.15) 1.24 (0.98 – 1.81) 2001D 31.9 (17.9 – 88.4) 8.95 (4.87 – 24.1) 2002 1.44 (1.18 – 1.79) 0.87 (0.68 – 1.14) 2003 1.47 (1.18 – 1.83) 1.09 (0.85 – 1.37) 2004 1.59 (0.87 – 4.37) 0.72 (0.37 – 1.95) 2005 A 3.02 (2.32 – 4.12) 1.66 (1.23 – 2.36) 1.11 (0.90 – 1.38) 0.74 (0.59 – 0.95) 2006 B 2007 B 2.07 (1.57 – 2.63) 1.76 (1.32 – 2.32) 2008 B C 1.59 (x.xx – x.xx) 0.61 (x.xx – x.xx) Geomean 2.14 (1.35 – 3.39) 1.17 (0.80 – 1.71) A In-river SAR is combination of groups C0 and C1 in derivation of TIR and D. B TIR and D use SAR for TX estimated with Group T and C0 with combined Group CRT. C Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) D For migration year 2001, the SAR(C1) value is used in the derivation of TIR and D. Table 4.14 Estimated TIR and D of of PIT-tagged Imnaha AP summer Chinook for 1997 to 2008 (with 90% confidence intervals). Lower limit values >1 are highlighted in yellow and upper limit values <1 are highlighted in blue. After 2005, transport operations initiated on a delayed start date compared to previous years. Mig. Year 4 5 6 TIR D 1997 1.36 (0.83 – 2.37) 0.45 (0.24 – 0.92) 1998 1.55 (0.93 – 3.15) 0.87 (0.51 – 1.72) 1999 1.89 (1.40 – 2.51) 1.11 (0.75 – 1.72) 2000 1.29 (1.06 – 1.58) 0.82 (0.56 – 1.25) 2001D 10.8 (4.94 – 39.8) 4.15 (1.83 – 15.3) 2002 1.75 (1.07 – 3.03) 0.95 (0.54 – 1.78) 2003 1.21 (0.80 – 1.86) 0.91 (0.57 – 1.41) 2004 1.64 (0.54 – 5.32) 0.94 (0.27 – 3.14) 2005 A 1.77 (0.91 – 3.93) 1.11 (0.54 – 2.69) 2006 B 0.62 (0.42 – 0.89) 0.36 (0.24 – 0.54) 2007 B 1.63 (1.04 – 2.39) 1.17 (0.71 – 1.82) 2008 B C 1.43 (x.xx – x.xx) 0.51 (x.xx – x.xx) Geomean 1.68 (1.20 – 2.36) 0.90 (0.66 – 1.24) A In-river SAR is combination of groups C0 and C1 in derivation of TIR and D. B TIR and D use SAR for TX estimated with Group T and C0 with combined Group CRT. C Complete 2-salt for 2008 adult returns through July 26, 2010 (bootstrap CI to be computed after final loading of returning adults in September) D For migration year 2001, the SAR(C1) value is used in the derivation of TIR and D. In the absence of differential delayed mortality below Bonneville Dam of transported fish compared to in-river migrants, D would be equal to one. When D 88 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 estimates are >1, the post-BON mortality is greater for the in-river migrants and when D estimates are <1, it is greater for the transported smolts. Statistical significance was demonstrated for D ≠1 (two-tail test) when either the lower limit of the 90% confidence interval for D was >1 or the upper limit of the 90% confidence interval for D was <1. With the exception of 2001, there were few years and hatcheries where a significant D >1 (post-BON mortality of in-river fish is greater than that of transported fish) estimates was obtained (Figure 4.6). A significant D >1 estimate was also demonstrated for McCall Hatchery Chinook in 2005 and 2007 (Table 4.13). On the other hand, a significant D <1 (post-BON mortality of transported fish is greater than that of inriver fish) was demonstrated for PIT-tagged wild and Dworshak Hatchery Chinook in nearly half the years (Tables 4.9 and 4.11). Since transport SARs were only significantly greater than in-river SARs in 2 years for PIT-tagged wild Chinook and Dworshak Hatchery Chinook smolts, and post-BON mortality of transported fish was not significantly less than post-BON mortality of in-river fish, it appears that transportation provides no survival advantage over allowing wild Chinook and Dworshak Hatchery Chinook to migrate in-river. Although Snake River wild and hatchery populations demonstrated differences in estimated magnitude of TIRs and Ds, the historical patterns for these were similar among wild and hatchery populations. TIRs were higher for hatchery fish than wild fish, but the TIR pattern for the wild population tracked well with those of the hatchery populations across years (Figure 4.5). Similarly, hatchery fish had higher D values than wild fish, but wild and hatchery Ds also tracked well across years (Figure 4.6). Figure 4.6 Trend in D on the natural log scale for PIT-tagged Snake River hatchery and wild Chinook in migration years 1994-2007. The grey reference line denotes a D value of 1 (in-river and transport post-BON survivals are equal). After 2005, transport operations initiated on a delayed start date compared to previous years. D calculation for 2001 and 2005 differs from other years as in-river SAR component of ratio includes C1 fish (see methods). Data from Tables 4.9–14. 89 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Wild and hatchery steelhead The TIR estimates for the PIT-tagged wild and hatchery steelhead aggregates exceeded 1 in nine of 11 years, with statistical significance in 7 of the 11 years for wild stocks and 5 of the 11 years for hatchery stocks (Tables 4.15 and 4.16). The 11-year geometric means were similar and significantly greater than 1 for the PIT-tagged wild and hatchery steelhead aggregates (3.00 for wild stocks and 2.91 for hatchery stocks). Similar to Chinook salmon TIRs, steelhead TIRs were markedly higher in 2001 than during all other years as seen in the TIR trend across years for both hatchery and wild steelhead (Figure 4.7). Despite the marked increase in transport SAR for wild steelhead in 2007 (the highest in the time-series; Figure 4.3), when compared with in-river outmigrants, the TIR is the 6th highest in the time-series (Figure 4.7). For hatchery steelhead the time-series of transport SAR is consistently higher than in-river groups after 2000 (Figure 4.3) though the TIR value decreases in 2006 and 2007. A variety of operational and environmental factors that may have influenced the in-river SARs and resultant TIRs in 2006 & 2007 include: allowing early outmigrants to pass via in-river routes, the increased spill percentage as compared to earlier years, or the increased in-river population produced by a lower transportation percentage (Figure 1.4). Also, steelhead tend to migrate faster and have higher in-river survivals in years of better discharge, and the April 15 to June 15 average discharge in 2006 was the highest since the late 1990’s (Figure 1.4). Figure 4.7 Trend in TIR on the natural log scale for PIT-tagged Snake River hatchery and wild steelhead in migration years 1997 to 2006. The grey reference line denotes a TIR value of 1 (in-river and transport SARs equal). After 2005, transport operations initiated on a delayed start date compared to previous years. TIR calculation for 2001, 2004, and 2005 differs from other years as inriver SAR component of ratio includes C1 fish (see methods). Data from Tables 4.15–16. 90 1 Table 4.15 Estimated TIR and D of PIT-tagged wild steelhead for migration years 1997 to 2007 (with 90% confidence intervals). Lower limit values >1 are highlighted in yellow and upper limit values <1 are highlighted in blue. After 2005, transport operations initiated on a delayed start date compared to previous years. Mig. Year 1997 1998 1999 2000 2001D 2002 2003 2004 A 2005 A 2006 B 2007 B C Geomean 2.20 0.20 2.28 1.45 37.0 4.25 4.41 14.3 4.88 0.85 2.95 3.00 TIR (0.00 – 8.16) (0.00 – 0.70) (1.15 – 4.38) (0.77 – 2.40) (10.6 – 94.6) (2.12 – 7.67) (2.74 – 7.73) (7.19 – 42.1) (3.01 – 7.98) (0.49 – 1.80) (2.29 – 3.94) (1.42 – 6.35) 1.18 0.11 1.07 0.50 1.46 2.24 1.75 2.69 1.30 0.52 1.22 0.99 D (0.00 – 5.74) (0.00 – 0.41) (0.53 – 2.09) (0.27 – 0.82) (0.40 – 4.40) (1.09 – 4.25) (1.04 – 3.16) (1.29 – 8.78) (0.76 – 2.30) (0.29 – 1.11) (0.90 – 1.77) (0.61 – 1.61) A In-river SAR is combination of groups C0 and C1 in derivation of TIR and D. TIR and D use SAR for TX estimated with Group T and C0 with combined Group CRT. C Incomplete steelhead adult returns until 3-salt returns (if any) occur after 7/1/2010 at GRA. D For migration year 2001, the SAR(C1) value is used in the derivation of TIR and D. B 2 3 Table 4.16 Estimated TIR, and D of PIT-tagged hatchery steelhead for migration years 1997 to 2007 (with 90% confidence intervals). Lower limit values >1 are highlighted in yellow and upper limit values <1 are highlighted in blue. After 2005, transport operations initiated on a delayed start date compared to previous years. Mig. Year 1997 1998 1999 2000 2001D 2002 2003 2004 A 2005 A 2006 B 2007 B C Geomean 2.21 0.58 0.87 2.20 59.7 1.51 2.65 10.3 8.44 1.50 1.66 2.91 TIR (0.99 – 5.66) (0.23 – 1.05) (0.48 – 1.41) (1.22 – 3.58) (0.00 – 215.6) (0.38 – 3.33) (1.93 – 3.71) (5.43 – 17.9) (5.04 – 13.4) (0.93 – 2.42) (1.22 – 2.16) (1.42 – 5.97) 0.92 0.39 0.41 0.55 2.40 0.60 1.43 1.85 3.19 1.01 0.92 0.99 D (0.36 – 2.67) (0.16 – 0.85) (0.22 – 0.70) (0.30 – 0.93) (0.00 – 10.0) (0.14 – 1.38) (0.99 – 2.10) (0.91 – 3.46) (1.86 – 5.37) (0.61 – 1.63) (0.66 – 1.30) (0.68 – 1.46) A In-river SAR is combination of groups C0 and C1 in derivation of TIR and D. No pre-assignment for hatchery steelhead, so one group; transport SARs estimated with TX smolts. C Incomplete steelhead adult returns until 3-salt returns (if any) occur after 7/1/2010 at GRA. D For migration year 2001, the SAR(C1) value is used in the derivation of TIR and D. B 4 5 6 7 8 The estimate of D was >1 in eight of 11 years for PIT-tagged wild steelhead and five of 11 years for PIT-tagged hatchery steelhead (Table 4.15 and 4.16). Statistically significant D >1 (lower limit of 90% CI >1) was demonstrated in only 3 years for wild stocks and 1 year for hatchery stocks, while statistically significant D <1 (upper limit of 91 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 90% CI <1) occurred in 2 years for wild stocks and 3 years for hatchery stocks. The sample sizes for wild and hatchery steelhead PIT-tag groups have been small, which results in few adult returns and rather large 90% confidence intervals for both TIR and D estimates The natural log D trend across years is presented for both hatchery and wild steelhead in Figure 4.8. Although differences arise between the estimates for wild and hatchery steelhead, the TIR and D data suggest that steelhead as a whole respond more favorably to transportation than do the listed wild Chinook. During 2006 and 2007, there is no statistical difference between D and one. Most of the D parameter may be expressed while in the ocean (Figure 6.2, chapter 6) however some delayed effects of transport on upstream adult success were still evident in these years (see chapter 6 for adult success comparisons). Figure 4.8 Trend in D on the natural log scale for PIT-tagged Snake River hatchery and wild steelhead in migration years 1997-2007. The grey reference line corresponds to a D value of 1 (inriver and transport post-BON survivals are equal). After 2005, transport operations initiated on a delayed start date compared to previous years. D calculation for 2001, 2004, and 2005 differs from other years as in-river SAR component of ratio includes C1 fish (see methods). Data from Tables 4.15–16. 92 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Discussion The long-term monitoring data provided by the CSS study groups for wild spring/summer Chinook, hatchery spring Chinook, hatchery summer Chinook, wild steelhead, and hatchery steelhead have demonstrated considerable variability in SARs among study groups and between years. Since 2005, the SARs of PIT-tagged wild and hatchery Chinook and steelhead have been increasing. A variety of operational and environmental factors during the smolt outmigration that may have influenced the inriver SARs and resultant TIRs in 2006 through 2008 include: allowing early outmigrants to pass via in-river routes (as a result of the later start of transportation in these years), the increased spill percentage as compared to earlier years, and the increased total in-river population produced by a lower transportation percentage (see Figure 1.4 and Appendix C for the transportation percentages). Additionally, the April 15 to June 15 average discharge in 2006 was the highest since the late 1990’s (Figure 1.4). The delayed transport approach with spill, begun in 2006 was consistent with ISAB recommendations for a multi-species perspective that spread the risk of potential negative influences from differing routes of hydrosystem passage across several species at once (ISAB 2008). This includes consideration of stocks not analyzed in this chapter such as Snake River Sockeye, fall Chinook, or Pacific Lamprey (ISAB 2008). However, information for Snake River sockeye should be available as adults come back from the 2009 outmigration (see Chapter 1 to 3 for sample sizes, annual juvenile metrics, and juvenile analyses). The TIR estimates have been used as the initial indicator of potential benefit for smolt transportation for each study grouping. The combination of exceptionally low inriver smolt survivals in 2001 and generally average survivals for transported smolts resulted in exceptionally large TIR values for all CSS groups of PIT-tagged fish for the 2001 migration year. Those TIRs indicated a substantial benefit for smolt transportation in 2001, under unusual environmental conditions, extreme drought, and hydrosystem operations which included no spill and maximization of smolt transportation. For the rest of the CSS evaluation years, TIR estimates indicate the relative smolt transportation performance for the PIT-tagged spring/summer Chinook has been as follows: no benefit for the wild spring/summer Chinook and spring Chinook from Dworshak and Catherine Creek hatcheries, mixed benefit for the summer Chinook from Imnaha Hatchery, and positive benefit in most years to the spring Chinook from Rapid River Hatchery and summer Chinook from McCall Hatchery. Overall, Snake River hatchery Chinook exhibited a generally more positive response to transportation and relatively lower levels of differential delayed mortality (higher D) than did wild populations. The annual SARs of Snake River wild and hatchery Chinook were highly correlated across years. There appears to be positive benefit of transportation to the PIT-tagged wild and hatchery steelhead aggregates in most years; however, small sample sizes for steelhead through 2007 warrant some degree of caution in the degree of confidence on the relative performance of transportation relative to in-river migration. Also, distribution of PIT-tags across the drainages that comprise the PIT-tag aggregates varies across years. For example, PIT-tagged wild steelhead from the Imnaha River drainage comprised 37 % of the 2007 wild steelhead PIT-tag aggregate, but 69 % of the transported smolts within the 93 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 PIT-tag aggregate due to their later passage timing at the dams coinciding more with the delayed transportation season. Likewise, PIT-tagged hatchery steelhead released from Wallowa Hatchery comprised 27 % of the total PIT-tag hatchery steelhead aggregate, but 85 % of the transported smolts within the PIT-tag aggregate since most PIT-tagged smolts from the other hatcheries in the aggregate followed the default return-to-river operations at the Snake River transportation sites. With the shift to large-scale PITtagging of hatchery steelhead with a high percentage pre-assigned to Monitor-Mode operations, which began in 2008 with Dworshak NFH and the Lower Snake River Compensation hatcheries and expanded in 2009 to include IPC Niagara Springs Hatchery, there will be an ability in future years to estimate SARs, TIR, and D for a more representative cross-section of A-run and B-run hatchery steelhead stocks released above Lower Granite Dam. Some of the relative transport benefit seen for steelhead may be due to their poorer in-river survival compared to Chinook. The relation between loge(TIR) and inriver survival rate from LGR to BON (SR) for PIT-tagged wild Chinook and wild steelhead suggests that transportation is detrimental when SR is above approximately 55% (Figure 4.10) Whereas SR estimates for the PIT-tagged wild Chinook aggregate have been above 55% in several recent years, the SR estimates for the PIT-tagged wild steelhead aggregate has only rarely exceeded 55%. Figure 4.10 Natural logarithm of Transportation : In-river Ratio (TIR) versus in-river survival rate (SR) for wild Chinook (open points) for juvenile migration years 1994-2008 and wild steelhead (filled points) for juvenile migration years 1997-2007. Broken lines represent the 95% prediction intervals for loge(TIR). 94 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Chapter 5 Adult passage success rates between dams, D, and the expression of delayed effects. Introduction In the early 1990s, Mundy et al. (1994) concluded that research results to date were not conclusive regarding the ability of transportation to improve returns to the spawning grounds (or hatcheries) due to problems associated with experimental design. Even if transportation provides an apparent survival improvement relative to juvenile migration through the hydrosystem (as measured by adult return to the dams), the benefit may not carry through to natal areas if transported fish were more likely to stray or die before spawning. One of several advantages of the CSS experimental design of tagging fish at hatcheries or in tributaries before release (rather than at the dams as in previous studies) is that it allows for partitioning survival rates by treatment of known-origin fish between locations along their juvenile and adult migrations. Hatchery Chinook SARs from smolts at LGR to adults at LGR are a primary focus of CSS and are addressed in detail in Chapter 4. The CSS PIT-tag data allow for evaluation of the relative upstream passage success of adults between Bonneville (BON) and Lower Granite dams (LGR) from transport and in-river groups to further partition the LGR-LGR SARs and assess the extent to which transportation may contribute to straying or poor upstream passage conversion. The capability of estimating the relative adult passage success between BON-LGR became possible in 2002 because adult PIT-tag detection devices were completed in all of the adult ladders at BON. Given that estimates of TIR and D both rely on smolt-to-adult survival rates (SARs) based on adult detections at Lower Granite Dam (LGR), these values include both an ocean mortality component and one occurring during upstream migration (i.e., between BON and LGR) in the year of adult return. Partitioning D, which is BONsmolt to LGRadult differential survival, into two segments can help to describe where any differences in survival took place. The 2005 and 2006 CSS reports Berggren et al. 2005b and 2006), contained an analysis/comparison of the inter-dam ‘drop out’ rates of hatchery and wild Chinook salmon. The 2008 and 2009 CSS reports (Berggren et al. 2008, Tuomikoski et al. 2009) included adult success rate estimates, the complement of drop out rates; these estimates were updated for CSS Snake River groups from migration years 2003-2007 and used to partition D into ocean and BONadult to LGRadult differential survival. Here we updated and extended the analyses from the 2009 report to include migration years 2000-2008 for all CSS Snake River groups. This chapter contains summaries of findings from previous annual reports (Berggren et al. 2003; 2005a; 2005b; 2006; 2008, Schaller et al. 2007) regarding adult migration (BON-LGR) and success by migration year for both transport and in-river study categories. We used these estimates to separate D into ocean and adult escapement partitions. Finally, descriptions of the available information on the observations of straying fish are provided and a straying rate for in-river and transported outmigrants is presented. 95 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Methods Adult passage success by migration year Adult success rates by migration year and ocean survival were estimated for Snake River CSS groups from migration year 2000-2008. Data on the number of PITtagged adults passing various dams within the FCRPS was used to estimate a success rate for returning adults from BON to LGR. Using data collected at PIT-tag interrogation systems on adult fishways, this quantity was directly estimated and compared between the transport (TX or T0) and in-river (C0 and C1) study categories in the CSS. The transport group in the 2009 report was composed of only first time detected and transported fish (T0). In this report, for years with a delayed initiation of transportation (after 2005) the transport group was expanded to include fish transported with a previous detection upstream (TX). This is a logical fit with the delayed transport protocol in these years and follows the CSS study design. Relative ocean survival (e.g., BON as juvenile to BON as adult) was estimated indirectly by removing the success rate from the differential delayed mortality estimate (the D estimate; see Chapter 4). Hatchery and wild Chinook and steelhead marked with PIT tags as juvenile fish in the Snake River basin were monitored at mainstem dams on their downstream migration; after spending one to three years in the ocean, the survivors were detected as they passed upstream as adults through the hydro system. PIT-tag detection systems have been installed in the fish ladders at BON, MCN, ICH, and LGR and allowed the tracking of PIT-tagged adults as they passed from lower Columbia River projects to upstream Snake River projects. The adult fish traverse about 286 river miles and encounter eight dams from BON to LGR. Once fish negotiate BON, they pass through tribal fisheries (between BON and MCN) and a sport fishery in both the Columbia and Snake Rivers. The detections of adults decrease at upriver sites as a result of the combination of straying and both harvest and passage mortality. The adult success rate is the proportion of returning PIT-tagged adults that passed BON and were detected at LGR. This calculation requires an estimate of the number of PIT-tagged adults (excluding jacks for Chinook) passing BON in the fish ladders. Beginning with return year 2002 there was the capability to detect nearly all PIT-tagged adult fish passing the three ladders at BON. However, since a portion of the fish swim over the weir crests and do not pass through the orifices where the detection equipment is installed, the detection rate for PIT-tagged adult fish at BON is very high but less than 100%. Upstream adult PIT-tag detections that were not detected at BON (e.g., detected at MCN, ICH, or LGR but not at BON) were used to estimate the BON detection efficiency. BON detection efficiency is the number of PIT tag detections at BON divided by the sum of BON detections and upstream detections not observed at BON. This parameter was then used to expand the number of BON adult detections in the adult success rate. The adult success rate was calculated as: Adult.success.rate GRAcount BON count BONefficiency which can be re-arranged as: 96 [5.1] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Adult.success.rate GRAcount BON efficiency BON count [5.2] The efficiency was calculated specific to each group of interest. First efficiency was calculated at BON by aggregating adult detections from the transported and in-river study groups. Detectability at BON of adults was likely the same regardless of juvenile history and this approach allowed for use of the maximum number of detections. Then adult success rates was calculated for adults with in-river and transportation juvenile histories. Because the C1 and C0 in-river groups had a much smaller sample size than the TX group, and few adults returned overall, the C0 and C1 were combined into group (CX) . Finally, the BONefficiency was used to correct the adult success rate for the TX and the CX subset from a particular migration year, species and release group (e.g. Dworshak Hatchery Chinook that out-migrated in 2007). The use of fish detected upstream that were not detected at BON to estimate BON efficiency was the best available measurement of this parameter. However, this nominal estimator of efficiency could have been inaccurate if fish passed BON undetected and through straying/harvest/mortality were never again detected. This problem was alleviated by comparing these two rates in a fraction (e.g., Success(TX or T0)/SuccessCx). The assumption here was that the rate for passing BON undetected and never being detected again was the same for the transported and in-river fish. Since the fish were from the same species/hatchery the assumption seemed reasonable. To calculate the differential survival in the ocean, both the juvenile and adult hydrosystem survival components were removed from the LGRsmolt to LGRadult SARs. We used D (see Chapter 4) for a particular group and divided by the differential adult success rate for that same group. The result is an estimate that compares ocean survival of fish that were transported to ocean survival for fish with an in-river history (shown as T0 here but the same calculation applies when using the TX group (i.e. after 2005): SAR T0 Success ST T0 Ocean.survival.differential Success SAR C0 Cx SR [5.3] Bootstrapped 90% confidence intervals for the success rates were calculated using a nonparametric percentile bootstrap with 1,000 iterations in program R (R Development Core Team 2010). Bootstrapped confidence intervals for D are presented in chapter 4 of this report. Modeling success rates vs. smolt outmigration experience and return year conditions We updated the logistic regression analysis presented in Chapter 6 of the CSS 2009 report with additional years’ data and, follow that approach to further bolster our sample size, included individuals marked at Lower Granite Dam. The relationships between upstream adult success and juvenile outmigration experience was evaluated as 97 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 well as riverine conditions during adult upstream migration. For this exercise, adult success was defined as simply a detection of an adult at LGR that was previously detected at BON. Individuals were excluded if they were not detected as an adult at BON. This analysis was performed for hatchery Chinook, wild Chinook, hatchery steelhead, and wild steelhead separately. CSS-affiliated hatchery marks were relied upon because there was incomplete coverage of the in-river group across years for hatchery Chinook and steelhead that were marked at LGR. For the wild groups LGR marking was incorporated because there was consistent marking of both transported and in-river migrants across years. For Chinook salmon, only >1-ocean adults (i.e., we excluded jacks) from migration years (MYs) 2000-2008 were included in the analysis that were detected as adults by the PIT-tag interrogation sites at BON in return years (RYs) 20012010. For steelhead, individuals from MY’s 2001-2008 which were detected at BON as adults in RYs 2001-2009 were included; because of the potential for overwintering behavior to bias the success rate, RY 2010 was excluded for steelhead. Within the context of the logistic regression-based assessment of transportation effects, we also wished to account for variation in BON-LGR survival that could be attributed to in-river migration conditions. Specifically, given the results from the University of Idaho’s radio telemetry work (Keefer et al. 2004; Naughton et al. 2006), The influence of discharge, spill, and water temperature on adult passage success was quantified. These variables were summarized using records from the Fish Passage Center and USACE’s websites. Discharge and temperature data were summarized for BON (i.e., as a proxy for Columbia River conditions) and averaged across 2-week time blocks in each RY. Similarly, spill was summarized as average Lower Columbia (BON, TDA, JDA, and MCN, averaged) values for the same time blocks. Environmental variables were matched with individual fish records based on their BON arrival date. The same approach was followed as used in the 10-year report and 2009 CSS annual report of utilizing Lower Columbia in-river variables because the majority of adults (hatchery Chinook: 2032/2464, or 82%; wild Chinook: 534/675, or 79%, hatchery steelhead: 253/296, or 85%; wild steelhead: 519/651, or 80%) that failed to arrive at LGR dropped out before MCN, and in-river variables are correlated across sites. The effects of both transportation history and management/environmental conditions (i.e., Lower Columbia flow, spill, and temperature) were evaluated on the upstream migration success of individual fish using logistic regression. We followed the same model structure used in the 2009 CSS annual report. Thus, for the hatchery groups, 11 a priori models were fitted describing an individual’s survival response (0 = unsuccessful; 1 = successful) as a function of a combination of transportation and/or management/environmental predictor variables. Because fish marked at LGR were included and to control for any possible difference between these and CSS-affiliated marked fish, a dummy variable (“LGR.marking”) was added for LGR marked wild origin individual’s in the wild fish model sets. Therefore, the wild fish model sets included 22 total models. An AIC-based model selection approach was used to determine the level of support for different models (i.e., hypotheses). To asses the importance of predictor variables in each model set, the “relative variable importance” was calculated by summing the Akaike weights across all the models in the set where a particular variable occurs (Burnham and Anderson 2002; pg 168). Finally, we assessed slope parameter 98 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 sign (+/-) and significance (using a t-test; alpha = 0.05) from our top model(s) in each model set. Observations of straying and straying rates A summary of the data was included for fish detected outside the assumed migration corridor between BON and LGR. In this effort, we looked at all individuals from Snake River CSS groups from migration year 2000-2008 that had detections outside of the FCRPS. Although new observation sites are added to the PTAGIS database every year, the historical record for these straying fish was limited. For example, while adult detection capability at PRD has existed since 2003, detection capability has been available in the Deschutes and John Day rivers only since 2007 and 2008. Nonetheless, these data were compiled to characterize where presumed straying fish have last been observed. We include descriptions of where strays were detected and provide calculated straying rates for Chinook and steelhead. For the purpose of describing where strays were last detected, a stray was defined as any adult fish detected outside the FCRPS and below LGR without a subsequent detection within the FCRPS. A stray rate for Chinook was calculated both with and without jacks. Most of the Chinook strays were found in the Mid Columbia River; we pooled data for hatchery Chinook from migration years 2001-2008 to overlap with potential adult detection in this area. Only seven stray wild Chinook were detected so a rate was not calculated for this group. The majority of the steelhead strays were found in lower Columbia River subbasins (Deschutes and John Day rivers); we pooled steelhead data from migration years 2005-2008 to overlap with the detection of adults in this area. The stray rate was the sum of the strays detected at BOA divided by the total number of adults detected at BOA for a particular group of interest. This was calculated for both adults that were transported as juveniles and those that emigrated in-river. To test for a significant difference between these estimates, we used a non-parametric bootstrap approach (e.g., resampling with replacement) and calculated a new test statistic θ where, θ = Straying_ratetransport – Straying_ratebypassed. The 90% confidence interval around this statistic in relation to the value zero was used to indicate whether Straying_ratetransport was different than Straying_ratebypassed. At best, any straying rates would be minimal conservative estimates, because detections are not distributed across the Columbia Basin for all years, detection efficiencies at some of the newer detectors have not been established, and there are likely potential straying sites without PIT-tag detection. Results Adult passage success by migration year The counts of adults at BON and LGR for the 2000-2008 smolt migration years in each of the CSS groups are shown in Table 5.1 (see end of chapter). The geometric mean of the BON detection efficiency for Chinook ranged from 94.6% to 99.1% across migration year groups. This is similar to those calculated for Chinook in the 2005 annual report (range: 93.1% to 98.3%; CSS 2005 annual report, Table 58). The adult success 99 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 rates calculated from these counts are shown in Figure 5.2, Figure 5.3, and Table 5.3 (see end of chapter) along with the success rate differential (i.e., SuccessT0/SuccessCx). The geometric mean success rate differential across years for hatchery Chinook, wild Chinook, hatchery steelhead and wild steelhead were 91%, 93%, 92%, and 90% respectively. The geometric mean of the BON detection efficiency for steelhead was slightly less than for Chinook and ranged from 80.1% to 99.4% with the lowest rate for migration year 2000. The 2000 migration year is low because adult steelhead could have passed BON undetected in the summer/fall of 2001 and subsequently passed LGR with a detection in the spring of 2002. However, using the efficiency to expand the number of BON adult detections in the adult success rate allows for the inclusion of the 2000 migration year for steelhead in these analyses. In cases where each of the individual fish detected at upstream sites was also detected at BON, the efficiency and the adult success rate are 100%. So, given equation 5.2, the inclusion of the BON detection efficiency in calculation of the adult success rate adjusted the value of the adult success rate down by as much as 6.9% but more typically by 5% or less. The adult passage success rates of fish that were transported (T0 or TX) and fish that emigrated in-river (Cx) are shown with 90% confidence intervals in Table 5.3. The success rate differential estimates are shown in with their 90% confidence intervals in Table 5.3, Figure 5.2 and Figure 5.3. In a few cases, 90% confidence intervals could not be calculated because too few adults were detected in all, or the number of detections at BON was the same as the number at LGR. For example, the 2001 in-river Catherine Creek group had 3 adults which resulted in many bootstrap iterations having a zero in the denominator of the differential success rate and thereby an upper confidence interval of ∞ (shown as Inf in Table 5.3). All 8 of the adults for the 2005 Imnaha CX hatchery group that passed BON also passed LGR resulting in no variation when bootstrapping and a confidence interval from 1-1 (Table 5.3). As with D, when the value of the adult success rate differential is above or below one, this indicates that transport was beneficial or detrimental for the group being measured respectively. The point estimate of the adult success rate differential for transported to in-river fish was below one on 52 of 69 occasions (Table 5.3, Figure 5.2, Figure 5.3). The 90% confidence interval around this statistic in relation to the value 1 can be used to indicate whether transport was statistically beneficial or detrimental in regards to the adult success rate in each case (similar to D in Chapter 4). If the upper confidence interval was less than one, we conclude that, at alpha level of 10%, the practice of transportation was detrimental in regards to the adult success rate portion of the SAR. If the lower confidence interval is more than one, then transportation is found to be beneficial in regards to adult success. In Table 5.2, the upper confidence interval of the adult success rate differential was less than one 21 times, more than one three times, and straddled one 45 times. This is statistically significant evidence indicating that the transportation of smolts can negatively affect adult success and rarely has a positive effect on adult success. Partitioning D When removing the differential adult success from D, the differential ocean survival remains. The differential ocean survival is displayed in the bottom panel of 100 1 2 3 4 5 6 Figure 5.2. Here, many values are similar in pattern to those for D (top panel; Figure 5.1 and 5.2;) as the ocean survival represents the greatest portion of D temporally. There is a marked contrast between the differential adult success rates for wild and hatchery steelhead and the differential ocean survival (middle and lower panel; Figure 5.2). So, despite some positive effects measured by D for hatchery and wild steelhead, there remains a measureable negative effect once adults enter the hydrosystem. 101 1 2 3 4 5 6 7 8 9 Figure 5.1 The three panels display the log transformed D, differential adult success, and differential ocean survival in the top middle and bottom panels respectively for CSS hatchery and wild yearling Chinook. Each differential compares groups that emigrated via transportation (numerator) and inriver (denominator). In each panel, when the log-transformed point estimate is above zero (grey reference line) transported smolts survived at a higher rate, when below zero, in-river emigrants survived at a higher rate. Cases where this was significant for the differential adult success (middle panel) are circled in red. 102 1 2 3 4 5 6 7 8 9 10 Figure 5.2 The three panels display the log transformed D, differential adult success, and differential ocean survival in the top middle and bottom panels respectively for hatchery steelhead (red triangles) and wild steelhead (yellow triangles). Each differential compares groups that emigrated via transportation (numerator) and in-river (denominator). In each panel, when the log-transformed point estimate is above zero (grey reference line) transported smolts survived at a higher rate, when below zero, in-river emigrants survived at a higher rate. Cases where this was significant for the differential adult success (middle panel) are circled in red. 103 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Modeling success rates vs. smolt outmigration experience and return year conditions Consistent with the 10-year report (Schaller 2007; Chapter 6), and the results of the differential success rate comparisons in this chapter, our AIC-based model-selection exercise also demonstrates an effect of transportation history on upstream adult migration success. For wild Chinook, the best model describing individual migration success included transport and flow effects (Table 5.3). With the additional year’s data, this top model had higher weight than in the CSS 2009 annual report, although the top four models had nearly the same AICc score. The relative variable importance across all models in the set for wild Chinook was 100%, 100%, 47%, 25%, and 24% for transport, spill, LGR.marking, and temperature, respectively. Because the top four models in this set were nearly indistinguishable in their AICc scores, we tested for significance of the coefficients in each model. The transport (-) and flow (+) variables were significant in each case while the temperature and LGR.marking variables were not significant . For hatchery Chinook, the best model included transport, flow, and temperature effects (Table 5.4). With the additional data, the relative variable importance was 100%, for all four variables. For the top model, transport (-), temperature (+) and flow (+) were all significantly different from zero. The best model for wild steelhead included transport, spill and temperature effects. The relative variable importance was 100%, 100%, 100%, 43%, and 27% for transport, spill, flow, LGR.marking, and temperature, respectively. Because the top two models differed from the first by a ∆ AICc of < 2 (Table 5.5), we tested for significance of the coefficients in each model. In each case, the transport (-), spill (-), and temperature (+) variables were significant and the LGR.marking variable was not significant. Similar to the CSS 2009 report, for hatchery steelhead, the best model contained only the transport variable though each of the top five models differed by a ∆ AICc of ~ 2 (Table 5.6). The relative variable importance was 100%, 53%, 37%, and 33% for transport, spill, flow, and temperature, respectively. We tested for significance of the coefficients in each of the top four models. In each case, the transport (-), spill (-), and flow (+) variables were significant while the temperature variable was not significant across the top five models. Observations of straying and straying rates The adult success rate reflects a combination of fishing and other mortality and straying between BON and LGR. Here, we summarize data from salmon and steelhead individuals of Snake River Basin origin marked as part of the CSS for the 2000-2007 migration years that might be categorized as strays. We defined strays as any fish detected at any site other than BON, MCN, ICH, or LGR during the BON to LGR adult migration. We present these results to indicate where wild and hatchery steelhead and Chinook may stray to or overwinter; for this exercise we included strayed jacks for Chinook. When describing strays by area of last detect we organized these into three categories: Snake River (above the Snake River-Columbia River Confluence) and the Columbia River either above or below its confluence with the Snake River. 104 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 In the 2009 report, information was available for only 43 adult salmon and steelhead individuals with “out-of-hydrosystem” detections whereas, with the additional year’s data, we summarize information for 87 adults. These are summarized by area of last detection in Figures 5.3-5.4. All but fourteen (84%) of these adults were collected and transported as juveniles. Of these 87 individual adult salmon, 72 (83%) did not succeed in their migration to or above LGR. Transported fish from Dworshak hatchery were detected outside of the FCRPS more commonly than any other group; all of the Dworshak Hatchery origin Chinook strays were detected within the Columbia upstream of the Snake River mouth (Figure 5.3). All but one of these fish were never detected after their mid Columbia River detection. This is in sharp contrast to Rapid River hatchery, which had a similar number of PIT tagged fish as Dworshak over these years (Appendix A) but had only 2 detects outside the FCRPS. Also, there was only one adult that emigrated in-river from Dworshak hatchery that was detected outside the FCRPS. The geometric mean of the transport percentage for the PIT tagged juveniles from Dworshak over these years was 50%. Seven individuals from McCall and Catherine Creek hatcheries had last detects in the Deschutes and John Day rivers. However, it is important to keep in mind that adult detection capability has only been available here since 2007. Six of these seven individuals were transported as juveniles. These stocks were not detected in the Mid Columbia and represent the only CSS hatchery Chinook groups detected in these lower Columbia River tributaries (Figure 5.3). Two and five wild Chinook were detected in the Deschutes/John Day and Mid Columbia rivers. Steelhead presence outside the presumed migration corridor may be partially due to the selection of a cold-water holding or overwintering refugia before completing the adult migration the following spring. Three times as many of these individuals were later detected passing LGR as compared to Chinook (Figure 5.3-5.4). Most of the individual steelhead adults detected outside the FCRPS were last seen in the Deschutes or John Day river systems. This is in contrast with Chinook, which mostly strayed to the Columbia River system above the confluence with the Snake River. In total, 16 wild or hatchery steelhead were last detected in the Deschutes or John Day rivers. 31 32 33 34 35 36 37 38 39 It should be noted that several of these PIT tag detector sites were operating only over a portion of the years aggregated. The John Day river detector (JD1) and the Sherar’s falls detector (SHERFT) composed several “last detects” of these fish and these two sites have operated only since 2007; SHERFT operated only over a portion of 2007. This suggests that many fish that were never seen after their initial BON detection during years prior to 2007 may have been entering these Lower Columbia River tributary rivers. This is in agreement with the 2003 & 2004 CSS annual report (Berggren et al. 2005a) and the results in this chapter, where most of the drop-rate (the complement of success rate) for wild and hatchery Chinook took place between BON and MCN. 105 1 2 3 4 5 6 7 8 Figure 5.3 Summary of the last detection area for CSS Chinook originating in the Snake River Basin with detections other than at BON, MCN, ICH, and LGR dams (2000-2008 migration years). Jacks are included here. Most of these individuals did not eventually migrate to or above LGR. Grey and white colors denote transported and in-river outmigrants respectively. Some areas have several PIT tag detection sites (e.g., Deschutes R. could be Sherars Falls or Warm Springs Hatchery). Detections below Bonneville are not shown. 106 1 2 3 4 5 6 7 Figure 5.4 Summary of the last detection area for CSS steelhead originating in the Snake River Basin with detections other than at BON, MCN, ICH, and LGR dams (2000-2007 migration years). Most of these individuals did not eventually migrate to or above LGR. Grey and white colors denote transported and in-river outmigrants respectively. Some areas have several PIT tag detection sites (e.g., Deschutes R. could be Sherar’s Falls or Warm Springs Hatchery). Detections below Bonneville are not shown. 107 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Straying rates for adults that were transported as juveniles were significantly higher than for adults that had emigrated in-river. This relationship was true for Chinook (with or without jacks) and steelhead. Transported hatchery and wild Chinook strayed 17 and 16 times more often than their in-river counterparts respectively (0.52% vs. 0.03% and 0.97% vs. 0.06%). Transported hatchery and wild steelhead strayed 8 times more often than those that emigrated in-river (5.77% vs. 0.69%). All of the comparisons between transported and in-river outmigrants were statistically significant (Figure 5.3). The result that transported steelhead strayed about 5% more than their in-river counterparts is similar to results found with radio-tagging techniques by Keefer et al. 2008 (i.e. hatchery steelhead 5.3% higher and wild steelhead 2.6% higher). The magnitude of the increased straying rate for transported hatchery Chinook is lower here than that found by Keefer et al. 2008 (6.9% higher); this may be due to incomplete coverage of the straying area for PIT-tagged fish. Figure 5.3 Straying rates for hatchery Chinook (pooled across migration years 2001-2008) both with and without jacks and wild + hatchery steelhead (pooled across migration years 2005-2007). Each is shown for adults that were both transported as smolts and those that emigrated in-river. The bootstrapped 90% confidence interval for each rate is plotted. The confidence interval for the difference between bootstrapped straying rates (ie. θ) is printed above each pair of estimates. Strays were defined as adults detected outside the FCRPS without a subsequent detection within the FCRPS, including at or above LGR. 108 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Discussion D represents the differential delayed mortality between transported and in-river subsets of CSS groups. It appears that most of the positive effects are evident in the ocean component of the post-Bonneville survival. A lower adult success rate may be due to higher harvest and/or natural mortality or impaired homing, straying, and the subsequent greater exposure to harvest. The adult success rate differentials for these groups are typically below one in these years. The geometric mean of the adult success rate differential across all Chinook hatcheries and years is 91%. These results indicate that transportation of hatchery Chinook interferes with the adult success rate. The consequence is that the benefits of transportation decrease for these groups as adults move upstream. In contrast, the adult success rate differential for wild Chinook is nearer to and above one in years when many hatchery groups are not. The geometric mean of these adult success rates across all years is 91%. However, the ocean component differential is below one in all years but 2001. It may be that wild Chinook are more strongly imprinted at the time they enter the hydrosystem but overall the effects of transportation after passage of BON on the juvenile migration are negative as compared with in-river juvenile outmigration. D is generally higher for wild and hatchery steelhead than for other CSS groups (see Chapter 4) and this is typically expressed in the ocean differential component. There is evidence to suggest some overwintering behavior in the Lower and Mid Columbia for both transported and in-river out-migrants. However, when comparing the success of the two groups, the success of the returning adults is negatively affected by transportation. The geometric means of adult success rate differential for hatchery and wild steelhead across all years were 90% and 86% respectively. In the 2008 CSS annual report (Berggren et al. 2008), bypassed steelhead were found to have a slightly smaller median length than in-river steelhead for 2003-2005. If this difference resulted in an ostensibly less fit transported fish, this would make the transported population more susceptible to predation, and one would expect the ocean component differential for these groups to be less than one. However, since the opposite is true, if there is an effect of this size difference it does not preclude a positive effect of transportation in the ocean component. The adult success differential measures the relative success in surviving the straying/harvest/mortality gauntlet during the adult return for fish that out-migrated via the transportation program and in-river routes. This parameter expresses the combined difference in natural mortality, straying, and any changes in harvest pressure as a result of straying. A large majority of point measurements of the adult success rate differential were less than one (less than zero when log transformed). These results indicate that during 2000-2007, while transportation can increase or decrease ocean survival, it most often decreases the fidelity of adults returning to their natal habitat once in the hydrosystem. Consistent with these results, our AIC-based model-selection exercise also demonstrates a negative effect of transportation history on upstream adult migration success. The transport variable was in the top model(s) within each of four model sets 109 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 for wild and hatchery steelhead and wild and hatchery Chinook. This negative effect was always statistically significant. Strays were identified in the Lower Columbia and the Middle Columbia rivers from both Chinook and steelhead stocks. We identified a significant difference in adult straying rates for fish that were transported as juveniles when compared to those that had outmigrated in-river. Straying rates during the adult migration were higher for individuals that were transported as juveniles than those that outmigrated in-river. This was significant for Snake River hatchery Chinook and Snake River wild and hatchery steelhead. Run year survival rates of adults migrating upstream are important to harvest and hydro managers for comparisons to survival thresholds and performance standards and are used for run reconstruction and population viability assessments. A ‘return year’ overall adult rate is the success rate that represents all of the individuals in the Snake River run at large, weighted across their different juvenile in-river and transport route outmigration experiences. In the future we plan to estimate an overall adult passage success rate by return year. 110 1 Supporting tables Table 5.1 Counts of adults at LGR and BON for all Snake River CSS groups for the juvenile outmigration years 2000-2008. Counts are shown for fish with two different routes of passage as emigrating juveniles (transported [T0 before 2006, TX thereafter] and in-river groups [CX]). The “adds” column is for any individual adults seen at any upstream facility (MCA, ICH, or LGR) and not seen at BON; BON efficiency is calculated with these counts. Rear-type/ species/ Migr Yr LGR-CX BONCX BON-CX adds BON efficiency (TX + CX) N/A 5 1 8 12 0 5 3 N/A 176 143 360 246 547 239 228 Geom(ST) N/A 228 155 400 291 640 218 221 80.1% N/A 6 2 5 6 11 68 42 Geom (CH) N/A 97.9% 99.3% 98.7% 97.8% 98.4% 76.3% 84.0% 98.4% 18 96 61 246 265 10 6 8 0 0 0 8 2 0 0 0 2 7 5 9 10 30 5 11 Geom(ST) 3 8 8 10 14 33 7 16 96.4% 0 0 0 0 1 1 1 0 Geom (CH) 100.0% 100.0% 100.0% 97.0% 98.9% 97.7% 92.9% 100.0% 98.9% 24 60 31 131 117 31 3 9 33 80 41 164 132 41 3 11 2 4 0 3 7 1 0 1 22 169 49 232 185 201 145 109 Geom(ST) 21 193 60 281 210 223 167 126 97.6% 2 3 0 6 12 7 6 1 Geom (CH) 93.1% 97.5% 100.0% 98.0% 94.7% 97.1% 96.6% 98.6% 96.7% 9 34 30 111 33 30 83 44 10 44 39 124 52 29 105 53 1 3 0 6 2 2 1 2 13 50 43 137 50 51 81 52 Geom(ST) 14 57 51 154 52 55 99 57 97.3% 1 3 2 6 5 4 3 2 Geom (CH) 92.3% 94.4% 97.8% 95.9% 93.7% 93.3% 98.1% 96.5% 94.6% LGRTX BONTX BON-TX adds N/A 183 211 497 349 12 14 13 N/A 295 262 583 491 21 17 15 11 79 48 206 207 7 4 5 2000 HCH-CATH HCH-DWOR HCH-IMNA HCH-MCCA HCH-RAPH WCH HST WST 2001 HCH-CATH HCH-DWOR HCH-IMNA HCH-MCCA HCH-RAPH WCH HST WST 2002 HCH-CATH HCH-DWOR HCH-IMNA HCH-MCCA HCH-RAPH WCH HST WST 2003 HCH-CATH HCH-DWOR HCH-IMNA HCH-MCCA HCH-RAPH WCH HST WST 2004 111 Rear-type/ species/ Migr Yr LGRTX BONTX BON-TX adds HCH-CATH HCH-DWOR HCH-IMNA HCH-MCCA HCH-RAPH WCH HST WST 11 61 26 84 70 68 10 39 14 121 41 113 88 88 9 60 11 43 17 141 55 38 18 41 LGR-CX BONCX BON-CX adds BON efficiency (TX + CX) 0 3 1 1 2 2 2 1 7 46 8 25 23 48 33 5 Geom(ST) 7 66 12 41 25 59 39 7 97.3% 1 1 0 0 2 2 0 0 Geom (CH) 95.5% 97.9% 98.1% 99.4% 96.6% 97.4% 96.0% 98.5% 97.5% 14 65 23 168 69 49 29 52 1 2 0 2 5 1 1 1 4 30 8 41 20 20 43 17 Geom(ST) 4 35 8 49 23 28 56 17 94.8% 1 1 0 0 1 0 1 5 Geom (CH) 90.0% 97.1% 100.0% 99.1% 93.9% 98.7% 97.7% 92.0% 96.4% 13 57 46 173 107 80 25 48 25 93 62 200 150 92 35 82 0 0 0 3 4 0 0 0 23 80 55 153 69 79 154 32 Geom(ST) 34 131 66 186 102 101 192 46 99.4% 0 1 1 0 3 1 1 1 Geom (CH) 100.0% 99.6% 99.2% 99.2% 97.3% 99.5% 99.6% 99.2% 99.1% 12 16 23 78 41 39 56 134 15 27 27 93 64 47 84 176 0 0 0 1 2 0 0 3 20 127 70 152 71 167 194 138 Geom(ST) 22 172 90 187 95 197 238 175 99.0% 3 3 0 1 5 1 2 2 Geom (CH) 92.5% 98.5% 100.0% 99.3% 95.8% 99.6% 99.4% 98.6% 97.6% 99 65 98 135 237 128 123 113 141 186 346 166 2 0 1 3 5 2 86 124 124 147 225 435 113 209 162 196 303 517 0 0 0 4 6 6 Geom (CH) 99.2% 100.0% 99.7% 98.2% 98.3% 98.8% 99.0% 2005 HCH-CATH HCH-DWOR HCH-IMNA HCH-MCCA HCH-RAPH WCH HST WST 2006 HCH-CATH HCH-DWOR HCH-IMNA HCH-MCCA HCH-RAPH WCH HST WST 2007 HCH-CATH HCH-DWOR HCH-IMNA HCH-MCCA HCH-RAPH WCH HST WST 2008 HCH-CATH HCH-DWOR HCH-IMNA HCH-MCCA HCH-RAPH WCH 112 1 Table 5.2 Adult success rates for all CSS groups for the juvenile outmigration years 2000-2008. Adult success rate for the transported (T0 before 2006, TX thereafter) and in-river groups (CX), and the success rate differential of those rates are each shown with their 90% confidence interval. Values were the differential is significant different from one are shown in bold. Mig. RearYear type/Species Hatchery Success T0 Success Cx Success ratio T0/Cx 2000 HCH CATH NA NA NA HCH DWOR 0.608 (0.561 - 0.655) 0.756 (0.707 - 0.801) 0.804 (0.724 - 0.891) HCH IMNA 0.8 (0.759 - 0.84) 0.916 (0.877 - 0.954) 0.873 (0.813 - 0.936) HCH MCCA 0.841 (0.816 - 0.866) 0.888 (0.862 - 0.916) 0.947 (0.906 - 0.988) HCH RAPH 0.695 (0.659 - 0.728) 0.826 (0.787 - 0.863) 0.841 (0.785 - 0.9) WCH 0.562 (0.379 - 0.745) 0.841 (0.817 - 0.865) 0.669 (0.446 - 0.888) HST 0.628 (0.416 - 0.927) 0.836 (0.796 - 0.873) 0.751 (0.486 - 1.11) WST 0.728 (0.513 - 1.013) 0.866 (0.831 - 0.902) 0.84 (0.586 - 1.182) 2001 HCH CATH 0.611 (0.429 - 0.8) 0.667 (0 - 1) 0.917 (0.5 - Inf) HCH DWOR 0.823 (0.76 - 0.885) 0.875 (0.6 - 1) 0.94 (0.782 - 1.331) HCH IMNA 0.787 (0.701 - 0.868) 0.625 (0.333 - 1) 1.259 (0.825 - 2.468) HCH MCCA 0.812 (0.772 - 0.85) 0.873 (0.683 - 0.98) 0.93 (0.81 - 1.189) HCH RAPH 0.773 (0.732 - 0.815) 0.707 (0.495 - 0.904) 1.094 (0.845 - 1.573) WCH 0.684 (0.432 - 0.917) 0.888 (0.788 - 0.976) 0.77 (0.486 - 1.061) HST 0.619 (0.286 - 1) 0.663 (0.35 - 1) 0.933 (0.4 - 2) WST 0.625 (0.333 - 0.9) 0.688 (0.476 - 0.889) 0.909 (0.433 - 1.545) 2002 HCH CATH 0.677 (0.537 - 0.814) 0.975 (0.864 - 1.091) 0.694 (0.522 - 0.893) HCH DWOR 0.731 (0.643 - 0.826) 0.854 (0.812 - 0.892) 0.857 (0.747 - 0.983) HCH IMNA 0.756 (0.64 - 0.864) 0.817 (0.735 - 0.896) 0.926 (0.76 - 1.096) HCH MCCA 0.783 (0.727 - 0.837) 0.809 (0.767 - 0.85) 0.967 (0.881 - 1.062) HCH RAPH 0.84 (0.784 - 0.895) 0.835 (0.791 - 0.876) 1.006 (0.922 - 1.099) WCH 0.734 (0.615 - 0.845) 0.875 (0.836 - 0.912) 0.839 (0.695 - 0.968) HST 0.966 (0.943 - NA) 0.839 (0.795 - 0.884) 1.152 (1.087 - NA) WST 0.806 (0.538 - 1.108) 0.853 (0.799 - 0.905) 0.946 (0.625 - 1.32) 2003 HCH CATH 0.831 (0.597 - 1.066) 0.857 (0.677 - 1.019) 0.969 (0.636 - 1.425) HCH DWOR 0.729 (0.615 - 0.851) 0.828 (0.737 - 0.907) 0.881 (0.719 - 1.075) HCH IMNA 0.753 (0.644 - 0.867) 0.825 (0.728 - 0.914) 0.912 (0.756 - 1.109) HCH MCCA 0.858 (0.805 - 0.911) 0.853 (0.807 - 0.903) 1.006 (0.92 - 1.095) HCH RAPH 0.595 (0.486 - 0.705) 0.901 (0.811 - 0.984) 0.66 (0.522 - 0.825) WCH 0.966 (0.881 - 1.058) 0.865 (0.784 - 0.944) 1.116 (0.966 - 1.305) HST 0.775 (0.71 - 0.84) 0.802 (0.73 - 0.869) 0.966 (0.857 - 1.092) WST 0.801 (0.706 - 0.89) 0.88 (0.8 - 0.952) 0.91 (0.779 - 1.058) 2004 HCH CATH 0.75 (0.545 - 0.929) 0.955 (0.667 - 1.313) 0.786 (0.476 - 1.227) HCH DWOR 0.494 (0.417 - 0.57) 0.682 (0.587 - 0.78) 0.723 (0.584 - 0.894) HCH IMNA 0.622 (0.488 - 0.755) 0.654 (0.422 - 0.889) 0.951 (0.643 - 1.514) HCH MCCA 0.739 (0.672 - 0.806) 0.606 (0.47 - 0.735) 1.219 (0.986 - 1.593) HCH RAPH 0.768 (0.69 - 0.836) 0.889 (0.744 - 1.026) 0.865 (0.716 - 1.059) WCH 0.752 (0.676 - 0.824) 0.792 (0.702 - 0.884) 0.95 (0.807 - 1.105) HST 1.067 (0.802 - 1.478) 0.812 (0.713 - 0.904) 1.313 (0.964 - 1.944) WST 0.64 (0.538 - 0.743) 0.704 (0.4 - 0.986) 0.91 (0.636 - 1.668) 2005 HCH CATH 0.707 (0.515 - 0.889) 0.9 (0.462 - 1.789) 0.786 (0.327 - 1.857) HCH DWOR 0.642 (0.547 - 0.743) 0.832 (0.717 - 0.939) 0.772 (0.626 - 0.959) HCH IMNA 0.739 (0.583 - 0.882) 1 (1 - 1) 0.739 (0.583 - 0.885) 113 Mig. Year 2006 2007 2008 Reartype/Species HCH HCH WCH HST WST HCH HCH HCH HCH HCH WCH HST WST HCH HCH HCH HCH HCH WCH HST WST HCH HCH HCH HCH HCH WCH Hatchery MCCA RAPH CATH DWOR IMNA MCCA RAPH CATH DWOR IMNA MCCA RAPH CATH DWOR IMNA MCCA RAPH Success T0 0.832 (0.783 - 0.878) 0.748 (0.659 - 0.843) 0.766 (0.657 - 0.86) 0.606 (0.451 - 0.763) 0.725 (0.629 - 0.815) 0.52 (0.333 - 0.694) 0.61 (0.526 - 0.693) 0.736 (0.65 - 0.82) 0.858 (0.812 - 0.9) 0.694 (0.628 - 0.757) 0.865 (0.806 - 0.921) 0.711 (0.59 - 0.833) 0.581 (0.491 - 0.666) 0.74 (0.563 - 0.901) 0.584 (0.426 - 0.743) 0.852 (0.727 - 0.962) 0.833 (0.76 - 0.898) 0.614 (0.513 - 0.716) 0.826 (0.736 - 0.912) 0.663 (0.577 - 0.748) 0.751 (0.693 - 0.805) 0.798 (0.734 - 0.86) 0.575 (0.504 - 0.652) 0.693 (0.627 - 0.756) 0.713 (0.658 - 0.765) 0.674 (0.629 - 0.712) 0.762 (0.705 - 0.823) 1 114 Success Cx 0.829 (0.737 - 0.912) 0.816 (0.676 - 0.96) 0.705 (0.559 - 0.842) 0.75 (0.651 - 0.845) 0.92 (0.731 - 1.143) 0.676 (0.535 - 0.821) 0.608 (0.539 - 0.673) 0.827 (0.747 - 0.908) 0.816 (0.771 - 0.862) 0.658 (0.578 - 0.735) 0.778 (0.707 - 0.845) 0.799 (0.751 - 0.846) 0.69 (0.571 - 0.805) 0.841 (0.684 - 1) 0.727 (0.668 - 0.78) 0.778 (0.707 - 0.851) 0.807 (0.759 - 0.852) 0.716 (0.632 - 0.794) 0.844 (0.801 - 0.887) 0.81 (0.763 - 0.85) 0.777 (0.723 - 0.826) 0.755 (0.689 - 0.82) 0.593 (0.535 - 0.651) 0.763 (0.705 - 0.817) 0.737 (0.684 - 0.791) 0.73 (0.69 - 0.774) 0.832 (0.805 - 0.859) Success ratio T0/Cx 1.003 (0.89 - 1.14) 0.917 (0.742 - 1.157) 1.086 (0.863 - 1.415) 0.808 (0.583 - 1.067) 0.788 (0.598 - 1.031) 0.769 (0.633 - 0.972) 1.004 (0.906 - 1.131) 0.89 (0.811 - 0.985) 1.052 (0.996 - 1.113) 1.054 (0.944 - 1.201) 1.112 (1.023 - 1.223) 0.891 (0.841 - 0.946) 0.841 (0.722 - 1.016) 0.88 (0.74 - 1.082) 0.803 (0.748 - 0.874) 1.095 (1.001 - 1.204) 1.032 (0.977 - 1.096) 0.857 (0.773 - 0.971) 0.979 (0.932 - 1.032) 0.818 (0.78 - 0.869) 0.965 (0.909 - 1.038) 1.058 (0.974 - 1.159) 0.97 (0.884 - 1.075) 0.908 (0.848 - 0.982) 0.968 (0.901 - 1.042) 0.922 (0.871 - 0.977) 0.916 (0.887 - 0.947) 1 Table 5.3. Wild Chinook logistic regression model-selection results for CSS + LGR marked individuals. Note, Y = P(Success | X), where X is the variable in question. Models are ordered by AICc score. The entire set of models is shown. Those with a ΔAIC < 2 can be considered nearly equivalent. K is the number of estimated parameters (inclusive of variance). Model K AICc ∆ AICc wi transport + Qtot_Col 3 3460.1 0.0 53.0% transport + Qtot_Col + LGR.marking 4 3462.0 2.0 20.0% transport + Qtot_Col + T_Col 4 3462.1 2.0 20.0% transport + Qtot_Col + T_Col + LGR.marking 5 3464.0 4.0 7.0% Qtot_Col + LGR.marking 3 3475.5 15.4 0.0% Qtot_Col + T_Col + LGR.marking 4 3477.5 17.4 0.0% Qtot_Col 2 3477.9 17.9 0.0% transport + Qspill_Col 3 3478.7 18.6 0.0% transport + T_Col 3 3479.0 19.0 0.0% Qtot_Col + T_Col 3 3479.9 19.8 0.0% transport + Qspill_Col + LGR.marking 4 3480.3 20.3 0.0% transport + Qspill_Col + T_Col 4 3480.5 20.4 0.0% transport + T_Col + LGR.marking 4 3480.6 20.6 0.0% transport + Qspill_Col + T_Col + LGR.marking 5 3482.1 22.1 0.0% Qspill_Col + LGR.marking 3 3492.8 32.7 0.0% T_Col + LGR.marking 3 3492.8 32.7 0.0% Qspill_Col + T_Col + LGR.marking 4 3494.6 34.5 0.0% transport 2 3495.4 35.3 0.0% transport + LGR.marking 3 3496.7 36.6 0.0% Qspill_Col 2 3496.7 36.7 0.0% T_Col 2 3496.8 36.7 0.0% Qspill_Col + T_Col 3 3498.6 38.5 0.0% Qtot_Col = Flow at BON. Qspill_Col = spill at BON, JDA, MCN, IHR. T_Col = Temperature at BON. Transport is a dummy variables denoting transport at LGR, LGS or LMN. LGR.marking is a dummy variable denoting whether a smolt was marked at LGR or not. 2 3 4 5 6 Table 5.4. Hatchery Chinook logistic regression model-selection results for CSS marked individuals. Note, Y = P(Success | X), where X is the variable in question. Models are ordered by AICc score. The entire set of models is shown. Those with a ΔAIC < 2 can be considered nearly equivalent. K is the number of estimated parameters (inclusive of variance). Model K AICc ∆ AICc wi transport + Qtot_Col + T_Col 4 11018.7 0.0 98.0% transport + Qspill_Col + T_Col 4 11026.2 7.5 2.0% transport + T_Col 3 11038.3 19.6 0.0% Qtot_Col + T_Col 3 11043.3 24.6 0.0% Qspill_Col + T_Col 3 11053.8 35.1 0.0% T_Col 2 11063.0 44.3 0.0% transport + Qtot_Col 3 11100.1 81.4 0.0% Qtot_Col 2 11118.6 99.9 0.0% transport + Qspill_Col 3 11210.3 191.6 0.0% Qspill_Col 2 11224.9 206.2 0.0% transport 2 11227.4 208.7 0.0% See table 5.3 for variable names7 key. 115 1 2 3 4 5 6 7 8 9 10 11 12 13 Table 5.5. Wild steelhead logistic regression model-selection results for CSS + LGR marked individuals. Note, Y = P(Success | X), where X is the variable in question. Models are ordered by AICc score. The entire set of models is shown. Those with a ΔAIC < 2 can be considered nearly equivalent. K is the number of estimated parameters (inclusive of variance). Model K AICc ∆ AICc wi transport + Qspill_Col + T_Col 4 2809.0 0.0 52.0% transport + Qspill_Col + T_Col + LGR.marking 5 2809.6 0.6 39.0% transport + Qspill_Col 3 2814.7 5.7 3.0% transport + Qspill_Col + LGR.marking 4 2815.3 6.3 2.0% transport + Qtot_Col + T_Col 4 2816.5 7.6 1.0% transport + Qtot_Col + T_Col + LGR.marking 5 2816.7 7.8 1.0% transport + Qtot_Col 3 2817.6 8.7 1.0% transport + Qtot_Col + LGR.marking 4 2817.9 8.9 1.0% transport + T_Col 3 2819.4 10.5 0.0% transport + T_Col + LGR.marking 4 2819.5 10.5 0.0% transport 2 2820.9 12.0 0.0% transport + LGR.marking 3 2821.1 12.2 0.0% Qspill_Col + T_Col + LGR.marking 4 2823.4 14.5 0.0% Qspill_Col + LGR.marking 3 2830.0 21.1 0.0% Qspill_Col + T_Col 3 2831.8 22.8 0.0% Qtot_Col + T_Col + LGR.marking 4 2833.2 24.2 0.0% Qtot_Col + LGR.marking 3 2834.6 25.6 0.0% T_Col + LGR.marking 3 2836.2 27.3 0.0% Qspill_Col 2 2838.8 29.9 0.0% Qtot_Col + T_Col 3 2844.6 35.6 0.0% Qtot_Col 2 2845.9 36.9 0.0% T_Col 2 2848.1 39.2 0.0% See table 5.3 for variable names key. Table 5.6. Hatchery steelhead logistic regression model-selection results for CSS marked individuals. Note, Y = P(Success | X), where X is the variable in question. Models are ordered by AICc score. The entire set of models is shown. Those with a ΔAIC < 2 can be considered nearly equivalent. K is the number of estimated parameters (inclusive of variance). Model transport transport + Qspill_Col transport + T_Col transport + Qspill_Col + T_Col transport + Qtot_Col transport + Qtot_Col + T_Col Qspill_Col T_Col Qspill_Col + T_Col Qtot_Col Qtot_Col + T_Col See table 5.3 for variable names key. K 2 3 3 4 3 4 2 2 3 2 3 116 AICc 1407.6 1407.7 1408.6 1409.5 1409.6 1410.6 1416.4 1417.9 1418.4 1418.7 1419.9 ∆ AICc 0.0 0.1 1.0 1.9 2.0 3.0 8.9 10.3 10.8 11.1 12.3 wi 28.0% 27.0% 17.0% 11.0% 10.0% 6.0% 0.0% 0.0% 0.0% 0.0% 0.0% 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Chapter 6 Patterns in Annual Overall SARs Success of any hydrosystem mitigation strategy will require achievement of smolt-to-adult survival rates sufficient to meet recovery and rebuilding objectives, in combination with a program to maintain or achieve adequate survival in other life stages. An independent peer review of the transportation program in the early 1990s (Mundy et al. 1994) concluded: “[u]nless a minimum level of survival is maintained for listed species sufficient for them to at least persist, the issue of the effect of transportation is moot.” The Northwest Power and Conservation Council (NPCC 2009) adopted a goal of achieving SARs in the 2-6% range (minimum 2%; average 4%) for federal ESA-listed Snake River and upper Columbia River salmon and steelhead. For the populations in these listed groups, an overall SAR is the SAR that includes the survival of all outmigrating smolts weighted across their different in-river and transport route experiences; it is the SAR of an entire brood of smolts, irrespective of their route of passage through the hydrosystem. The NPCC (2009) Fish and Wildlife Program objectives for unlisted populations or listed populations downstream of the Snake River and Upper Columbia River basins are to “significantly improve the smolt-to-adult return rates (SARs) for Columbia River Basin salmon and steelhead, resulting in productivity well into the range of positive population replacement.” The NPCC (2009) also adopted a strategy to identify the effects of ocean conditions on anadromous fish survival and use this information to evaluate and adjust inland actions. The NPCC noted that while we cannot control the ocean, we can monitor ocean conditions and related salmon survival and take actions to improve the likelihood that Columbia River salmon can survive varying ocean conditions. A better understanding of the conditions salmon face in the ocean can suggest which factors will be most critical to survival, and thus provide insight as to which actions taken inland will provide the greatest restoration benefit. Analyses in this chapter address the extent to which wild spring/summer Chinook and steelhead population aggregates may be meeting the NPCC (2009) biological objectives. Parameters estimated in the CSS allow for partitioning first year ocean survival, S.o1, from SARs (Wilson 2003; Zabel et al. 2006; Tuomikoski et al. 2009; Petrosky and Schaller 2010), which can then be used to evaluate ocean and smolt migration factors that may influence ocean survival as called for in the Fish and Wildlife Program (NPCC 2009). The NPCC 2-6% SAR objectives are consistent with analyses conducted by the Plan for Analyzing and Testing Hypotheses (PATH), in support of the 2000 Biological Opinion of the Federal Columbia River Power System (FCRPS). Marmorek et al. (1998) found that median SARs of 4% were necessary to meet the NMFS interim 48-year recovery standard for Snake River spring/summer Chinook; meeting the 100-year interim survival standard required a median SAR of at least 2%. The NPCC (2009) SAR objectives did not specify the points in the life cycle where Chinook smolt and adult numbers should be estimated. However, the original PATH analysis for Snake River spring/summer Chinook was based on SARs calculated as adult and jack returns to the uppermost dam, adjusted for mainstem harvest rates (Marmorek et al. 1998); no adjustment was made for adult upstream passage loss or straying. PATH analyses also 117 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 did not identify specific SARs necessary for steelhead survival and recovery. However before completion of the FCRPS, steelhead SARs were somewhat greater than those of spring/summer Chinook (Marmorek et al. 1998). The Interior Columbia River Technical Recovery Team (ICTRT 2007) developed biological recovery criteria based on the Viable Salmonid Population concepts (McElhany et al. 2000). Additional SAR objectives may be associated with the IC-TRT recovery criteria for abundance and productivity when adopted or incorporated into a Recovery Plan, as well as with the objectives identified in Fish and Wildlife Program subbasin plans, and other State and Tribal fishery management plans. Regardless of specific future SAR objectives, the same types of data and analytical methods will be required in the future to evaluate the overall effectiveness of hydrosystem actions in addressing recovery and mitigation goals. To address these multiple objectives, we present bootstrapped SARs and confidence intervals based on CSS PIT-tagged adult returns to both Bonneville Dam (BOA) and the uppermost dam for Snake River fish (e.g., Lower Granite Dam; GRA). Alternative SAR objectives will likely require enumerating smolts and adults at different locations, depending on how broadly the objective is defined. That is, different adult accounting locations would be required if an SAR objective was defined narrowly for population persistence or more broadly to maintain productive natural populations with sustainable fisheries. The SAR estimates in this report are based on smolts at the uppermost dam (Lower Granite, McNary, John Day or Bonneville), and adults at either Bonneville Dam or the uppermost dam. We have made preliminary comparisons of these SAR estimates to the NPCC 2-6% SAR objectives, recognizing additional accounting for harvest, straying and other upstream passage losses may be needed in the future as NPCC and other SAR objectives are clarified. To compare historical population productivity in the smolt-to-adult life stage, it is necessary to account for changes in mainstem harvest rates and upstream passage success (Petrosky and Schaller 2010). Mainstem Columbia River harvest rates decreased markedly in the 1970s following construction of the FCRPS and the decline in abundance and productivity of upriver Columbia and Snake River populations. Therefore, we also present a time series of SARs for Snake River Chinook and steelhead based on smolts at the uppermost dam to adult returns to the Columbia River mouth for the 1964-2008 smolt migration years; this time frame spans completion of the FCRPS, decreases in Columbia River harvest rates and a period of variable ocean conditions. The NPCC 2-6% SAR objective for Chinook addresses the total adult return including jacks (i.e., 1-salt male Chinook). Therefore, in this chapter we present estimates of overall SAR with jacks included and the CSS standard reporting statistic of SARs with jacks excluded. Most other Chinook analyses in this and previous reports, are based strictly on adults (age 2-salt and older). These calculations include the generation of SARs by study category, TIR, D, and adult upstream migration success rates. By using only 2-salt and older returning Chinook adults in the estimation of the key CSS parameters, we are assuring that the results will be more directly reflective of the primary spawning populations (females and older males) in each Chinook ESU, region or subbasin. This is consistent with previous population viability (persistence) analyses (Marmorek et al. 1998; STUFA 2000; Karieva et al. 2000; Deriso et al. 2001; Peters and Marmorek 2001; Wilson 2003; Zabel et al. 2006; ICTRT 2007). 118 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 The primary objective for Snake River wild and hatchery spring/summer Chinook and steelhead is to update the long-term SAR data series for CSS study fish. Overall SARs are based on PIT-tagged fish, which experienced the same conditions as untagged smolts under a given year’s fish passage management scenario. Beginning in migration year 2006, this “run at large” group was represented by the Group TWS (Chapter 1). Prior to 2006, we estimated the proportion of run at large represented by each study group T0, C0 and C1. The CSS 2009 Annual Report (Tuomikoski et al. 2009) compared overall SARs using the two methods for migration years 2006 and 2007 (through 2-salt returns). Lastly, the overall SARs with jacks included are presented for all 15 years of PIT-tagged wild Chinook data and 12 years of PIT-tagged hatchery Chinook data (except for Catherine Creek hatchery Chinook, which has an 8-year history). The effect of including jacks in the overall SAR estimates are presented for the wild Snake River Chinook aggregate and each of the five CSS Snake River hatchery groups. Overall SARs for Snake River aggregate wild and aggregate hatchery steelhead are presented for 12 years beginning in 1997. CSS, Lower Snake River Compensation Plan (LSRCP) and Idaho Power Company (IPC) coordinated efforts to increase the PIT tagging of Snake River hatchery steelhead beginning in migration year 2008 so key parameters could be estimated at a finer resolution of run-type and subbasin: for Grande Ronde River A-run (GRN-A), Imnaha River A-run (IMN-A), Salmon River A-run (SAL-A), Salmon River B-run (SALB), and Clearwater River B-run (CLW-B). The primary objective for mid Columbia River (BON to PRD) wild and hatchery spring Chinook and steelhead is to establish and update SAR data series for subbasins in this region. Overall SARs are presented for 9 years (2000-2008) for John Day River wild Chinook, Carson Hatchery Chinook, and Cle Elum Hatchery Chinook. Overall SARs are also presented for one year (2008) for John Day wild steelhead. The CSS is compiling the data set to estimate SARs for mid Columbia wild steelhead SARs for the John Day River beginning in 2004, and the Deschutes River beginning in 2006; we expect to begin reporting these earlier years in the 2011 annual report. The primary objective for upper Columbia River (above PRD) wild and hatchery spring Chinook and steelhead is to establish and update SAR data series for subbasins in this region. Overall SARs are presented for 9 years (2000-2008) for Leavenworth Hatchery Chinook. Methods Estimation of 90% confidence intervals for annual SARs applicable to all mark populations For both Snake and Columbia River basin PIT-tag salmonid populations, nonparametric 90% confidence intervals are computed around the estimated annual overall SARs. The non-parametric bootstrapping approach of Efron and Tibshirani (1993) is used where first the point estimates are calculated from the population, and then the data is re-sampled with replacement to create 1000 simulated populations. These 1000 iterations are used to produce a distribution of annual SARs from which the value in the 119 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 50th ranking is the lower limit and value in the 951st ranking is the upper limit of the resulting 90% nonparametric confidence interval. Snake River basin populations originating above Lower Granite Dam Estimation of overall annual SARs for pre-2006 smolt migration years Annual estimates of LGR-to-GRA SAR reflective of the run-at-large for wild steelhead, hatchery steelhead, wild Chinook, and hatchery Chinook that outmigrated in 1997 to 2005 are computed by weighting the SARs computed with PIT-tagged fish for each respective study category by the proportion of the run-at-large transported and remaining in-river. The proportions of the run-at-large reflected by each of the CSS study categories C0, C1 and T0 were estimated as follows. First, the number of PITtagged smolts tj that would have been transported at each of the three Snake River collector dams (j=2 for LGR, j=3 for LGS, and j=4 for LMN) if these fish had been routed to transportation in the same proportion as the run-at-large is estimated. This estimation uses run-at-large collection and transportation data for these dams from the FPC Smolt Monitoring Program (SMP). The total estimated number transported across the three Snake River collector dams in LGR equivalents equals T0* = t2+t3/S2+t4/(S2S3). When a portion of the collected run-at-large fish is being bypassed as occurred in 1997, then there will be a component of the PIT-tagged fish also in that bypass category (termed C1* in this discussion). In most years, the C1* is at or near zero. When run-atlarge bypassing occurs, C1* = (T0 + C1) – T0*. The sum of estimated smolts in categories C0, T0*, and C1* is divided into each respective category’s estimated smolt number to provide the proportions to be used in the weighted SAR computation. The proportion of the run-at-large that each category of PIT-tagged fish represents is then multiplied by its respective study category-specific SAR estimate, i.e., SAR(C0), SAR(C1), and SAR(T0), and summed to produce an annual overall weighted SARLGR-toLGR for each migration year except 2001 as follows: SARAnnual w T0* * SAR T0 w C0* * SAR C0 31 32 33 w C1* * SAR C1 where, t t T0* t2 3 4 S 2 S 2 * S3 34 35 and, 36 37 38 39 40 reflect the number of PIT-tag smolts in transport and bypass categories, respectively, if collected PIT-tag smolts were routed to transportation in the same proportion as run-atlarge; and C1* T0 C1 T0* 120 1 w T0* 2 3 4 5 is the transported smolt proportion, w C0 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 T0* T0* C0 C1* C0 T C0 C1* * 0 is the non-detected (LGR, LGS, LMN) smolt proportion, and w C1* 1 w T0* w C0 is the bypass (LGR, LGS, LMN) smolt proportion. Estimation of overall annual SARs in smolt migration year beginning 2006 With the new approach of pre-assigning part of the release into a monitor-mode group (called Group T) that follows the routing of the untagged population the collector dams, we now have the opportunity to directly estimate the annual SARs with fewer parameters required to be estimated during intermediate steps before arriving at the final overall annual SAR estimate as occurred in pre-2006 years. In these cases, the estimation of the annual overall SAR is simply the number of returning adults in this group divided by the estimated number of smolts arriving LGR (both detected and undetected). The estimated number of PIT-tagged smolts arriving LGR is obtained by multiplying the release number in Group T by the estimated S1 (survival rate from release to LGR tailrace) obtained from running the CJS model on the total release. Group T reflects the untagged fish passage experience under a given year’s fish passage management scenario. Middle and Upper Columbia River basin populations Estimation of overall annual SARs in all smolt migration years Estimation of overall SARs for Chinook from Carson, Leavenworth, and Cle Elum hatcheries and wild Chinook and steelhead from the John Day River are based on estimated PIT-tagged smolts arriving the first PIT-tagged monitored dam and returning adults indexed at Bonneville Dam. The PIT-tagged smolt numbers are estimated by multiplying the release number by CJS reach survival rate from (i) release to MCN tailrace for Leavenworth and Cle Elum Hatchery Chinook (minus PIT-tagged smolts transported from MCN during the NOAA transportation studies of 2002 to 2005), (ii) release to JDA tailrace for John Day River wild Chinook and steelhead, and (iii) release to BON for Carson Hatchery Chinook, plus an overall SAR based on the total PIT-tagged smolts in the release from the Carson Hatchery facility for years when the estimated 121 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 release-to- BON survival rate exceeded one. Non-parametric 90% confidence intervals are estimated with the same bootstrapping protocol as used for the Snake River stocks. The CSS has compiled a historic time series of SARs for Snake River wild Chinook and steelhead beginning in 1964 prior to completion of the FCRPS. For years prior to the CSS PIT-tag based estimates, SARs were based on run reconstruction of smolt numbers at the uppermost Snake River dam and adults returning to the Columbia River from literature sources (Raymond 1988; Marmorek et al. 1998; Petrosky et al. 2001; Petrosky and Schaller 2010). As requested in the ISAB/ISRP (2008) review of the CSS Ten-Year Retrospective Report (Schaller et al. 2007), we continued the comparison of SARs based on PIT tags and run reconstruction (RR hereafter), 1998-2004, examined SAR methodologies and developed hypotheses for possible sources of bias in both the PIT tag and RR SARs for Snake River wild Chinook. First year ocean survival (S.o1) estimates were back-calculated from the overall SAR estimates for wild Snake River spring/summer Chinook and steelhead while taking into account year-to-year variability in hydrosystem survival and age composition of returning adults to the Columbia River mouth. The method of deconstructing SARs into first year ocean survival rates used here is described in Petrosky and Schaller (2010) (Appendix D), and was similar to approaches used in STUFA (2000), Wilson (2003) and Zabel et al. (2006).. Estimates of S.o1 can then be used to evaluate ocean and smolt migration factors that may influence ocean survival as called for in the Fish and Wildlife Program (NPCC 2009). Results Snake River Overall SARs Historic wild Snake River Chinook SARs (upper dam smolts-to-Columbia River returns, jacks included) decreased nearly five-fold from pre-FCRPS completion in the 1960s to the 1990s and 2000s (Figure 6.1). The geometric mean SAR during 1964-1969 was 5.9% compared to 1.1% during 1992-1999 and 1.3% since 2000. 122 10.0 % SAR (upper dam to Columbia River) 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0 1960 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 Migration year Figure 6.1. SARs from smolts at uppermost Snake River dam to Columbia River returns (including jacks) for Snake River wild Chinook, 1964-2008. SARs based on run reconstruction (1964-1985, 1992-1993, solid line) and CSS PIT tags (1994-2008, dots and solid line). The NPCC (2009) 2-6% SAR objective for listed wild populations is shown for reference. SARs (LGR-to-GRA, jacks included) of PIT-tagged Snake River wild Chinook had a geometric mean of 0.82% and exceeded the NPCC’s minimum SAR objective of 2% in only a single migration year (1999) during the period 1994-2008 (Table 6.1; Figure 6.2 top left plot). LGR-GRA SARs with jacks included were about 6% higher (geometric mean of SAR ratios) than SARs with jacks excluded (Table 6.1). SARs based on jack and adult returns to BOA were about 26% greater (geometric mean of SAR ratios) than SARs based on returns to GRA (Table 6.2) because of the combined effect of dam passage loss, straying and Zone 6 harvest (Chapter 5). The estimated overall SARs for Snake River hatchery spring and summer Chinook varied by hatchery and year (Figure 6.2; Tables 6.3-6.12). LGR-GRA SARs for Dworshak hatchery spring Chinook averaged (geometric mean) 0.54% and did not exceed 2% in any year during 1997-2008 (Table 6.3). LGR-GRA SARs for Rapid River hatchery spring Chinook averaged 0.85% and exceeded 2% in a single year (1999; Table 6.5). Catherine Creek hatchery Chinook SARs averaged 0.64% and exceeded 2% only in 2008 (Table 6.7). In general, the two hatchery summer Chinook populations had higher SARs than the hatchery spring Chinook populations. LGR-GRA SARs for McCall hatchery summer Chinook averaged (geometric mean) 1.48% and exceeded 2% in three years (1998-2000; Table 6.9). LGR-GRA SARs for Imnaha hatchery summer Chinook averaged 1.28% and also exceeded 2% in three years (1999, 2000 and 2008; Table 6.3). Although some difference in magnitude of SARs between groups was noted, the overall SARs (LGR-GRA) of wild and hatchery Snake River Chinook groups were highly correlated (average r = 0.76) during 1997-2008. 123 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Figure 6.2. Bootstrapped LGR-to-GRA SAR (with jacks included) and upper and lower CI for Snake River wild Chinook and five Snake River hatchery groups for migration years 1994-2008. Migration year 2008 is complete through 2-ocean returns only. The NPCC (2009) minimum 2% SAR for listed wild populations is shown for reference. Snake River wild steelhead SARs (upper dam smolts-to-Columbia River returns) decreased nearly four-fold from the 1960s (pre-FCRPS completion) to the 1990s and 2000s (Figure 6.3). The geometric mean SAR during 1964-1969 was 7.2% compared to 1.7% during 1990-1999 and 2.2% during 2000-2007. Snake River wild steelhead and wild Chinook SARs were highly correlated (0.70) during the 1964-2007 period. 124 % SAR (upper dam to Columbia River) 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 Migration year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 Figure 6.3. SARs from smolts at uppermost Snake River dam to Columbia River returns for Snake River wild steelhead, 1964-2007. SARs based on run reconstruction (1964-1996, solid line) and CSS PIT tags (1997-2007, dots and solid line). The NPCC (2009) 2-6% SAR objective for listed wild populations is shown for reference. The geometric mean SAR (LGR-to-GRA) of PIT-tagged Snake River wild steelhead was 1.41% during the period 1997-2007 (Table 6.13; Figure 6.4 top plot); SARs exceeded the NPCC’s minimum SAR objective of 2% in five of 11 migration years. SARs based on adult returns to BOA were about 35% greater (when comparing geometric mean of SAR ratios) than SARs based on returns to GRA (Table 6.13) because of the combined effect of adult dam passage loss, straying and Zone 6 harvest (Chapter 5). The estimated overall SARs (LGR-to-GRA) for Snake River hatchery steelhead averaged (geometric mean) 1.18% and exceeded 2% only in 2004 (Table 6.14; Figure 6.4, bottom plot). Overall SARs (LGR-to-GRA) of Snake River wild and hatchery steelhead aggregate groups were not highly correlated (r = -0.003) during 1997-2007. The first juvenile migration year with sufficient numbers of PIT-tagged smolts to estimate SARs for basin or run specific (e.g. Imnaha Basin A-run) Snake River hatchery steelhead stocks is 2008. However, the adult returns are incomplete with only one-salt returns through the adult run year 2009-2010. Minimum SARs (one-salt adults only) were in the 3-4% range for A-run hatchery steelhead in 2008 and less than 1% for B-run hatchery steelhead. Some differences in SARs between A-run and B-run stocks are expected because of their different ocean maturation and mainstem freshwater harvest rates. 125 Wild Snake River Steelhead 5.0 % SAR (LGR ‐ GRA) 4.0 3.0 2.0 1.0 0.0 1996 1998 2000 2002 2004 2006 2008 2006 2008 Migration year Hatchery Snake River Steelhead 5.0 % SAR (LGR ‐ GRA) 4.0 3.0 2.0 1.0 0.0 1996 1998 2000 2002 2004 Migration year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Figure 6.4. Bootstrapped LGR-to-GRA SAR and upper and lower CI for wild and hatchery Snake River steelhead for migration years 1997-2007. The NPCC (2009) minimum 2% SAR for listed wild populations is shown for reference. The first juvenile migration year with sufficient numbers of PIT-tagged fish to estimate SARs for Snake River hatchery sockeye is 2009 (see Chapter 1). CSS plans to begin reporting the time series of sockeye SARs in the 2011 annual report. Mid Columbia River Overall SARs In contrast to Snake River spring/summer Chinook and steelhead, no historic SAR data sets exist for the mid-Columbia Region extending back to pre-FCRPS completion. 126 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 The Yakama Nation fisheries staff estimated SARs of Yakima River natural origin spring Chinook based on run reconstruction of smolts at Chandler Dam to adults to the Yakima River mouth, beginning in smolt migration year 1983. Subbasin-to-subbasin SARs for Yakima River wild Chinook averaged 3.3%, ranging from 0.6% to 13.4% during 19832001 (Yakima Subbasin Summary; YIN and WDFW 2004). In addition, the Warm Springs Tribe has operated a smolt trap on the Warm Springs River since the late 1970s, from which it may be possible to calculate wild spring Chinook SARs using run reconstruction methods. The CSS will explore incorporating these run reconstruction SAR estimates into a long-time series for mid-Columbia Chinook in future analyses. The geometric mean SAR (JDA-to-BOA, without jacks) of PIT-tagged John Day River wild Chinook was 3.71% during the nine-year period 2000-2008 (Table 6.15; Figure 6.5 top plot). John Day wild Chinook SARs exceeded the NPCC’s minimum SAR objective of 2% in all but one migration year (2005; 1.82%). The PIT-tagged John Day River Chinook group represents an aggregate of three wild populations: the North Fork, Middle Fork, and upper mainstem John Day rivers. SARs of John Day River wild Chinook averaged (geometric mean of ratio) more than 5 times those of Snake River wild Chinook (Tables 6.15 and 6.1), and the wild SARs were highly correlated (r = 0.74) between regions during the period 2000-2008. The estimated overall SARs for mid-Columbia River hatchery spring Chinook varied by hatchery and year (Figure 6.5; Tables 6.16-6.17). REL-BOA SARs and BONto-BOA SARs for Carson hatchery Chinook averaged (geometric mean) 0.73% and 0.94% respectively during 2000-2008 (Table 6.16). MCN-BOA SARs for Cle Elum hatchery Chinook averaged 1.13% (Table 6.17). The two hatchery populations in the mid-Columbia region had much lower SARs than the John Day wild population. Although a difference in magnitude of SARs between groups was noted, the overall SARs of mid-Columbia wild and hatchery Chinook groups were highly correlated (average r = 0.84) between populations during 2000-2008. The CSS is compiling the data set to estimate SARs and confidence intervals for mid Columbia wild steelhead from the John Day River beginning with migration year 2004, and the Deschutes River beginning with migration year 2006. To date, we have only the 2008 migration year summarized for wild PIT-tagged John Day River steelhead. The 2008 one-salt SAR (JDA-to-BOA was 6.68% and exceeded the NPCC’s minimum SAR objective of 2% (Table 6.18). The PIT tagged John Day River steelhead group represents an aggregate of five wild populations: the North Fork, Middle Fork, South Fork upper mainstem and lower mainstem John Day rivers. Fish in the lower mainstem John Day population from tributaries downstream of the ODFW juvenile seining site are not trapped and PIT tagged. No PIT-tag SARs have been compiled for hatchery steelhead populations in the mid-Columbia region. There may be some potential for run reconstruction SARs for hatchery steelhead in the Deschutes and Umatilla subbasins. 127 Wild John Day Chinook 14.0 % SAR JDA to BOA 12.0 10.0 8.0 6.0 4.0 2.0 0.0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2006 2007 2008 2006 2007 2008 Migration year Carson Hatchery Chinook 5.0 % SAR REL to BOA 4.0 3.0 2.0 1.0 0.0 2000 2001 2002 2003 2004 2005 Migration year Cle Elum Hatchery Chinook 5.0 % SAR MCN to BOA 4.0 3.0 2.0 1.0 0.0 2000 2001 2002 2003 2004 2005 Migration year 1 2 3 4 5 Figure 6.5. Bootstrapped SAR (without jacks) and upper and lower CI for wild and hatchery Chinook from mid-Columbia region for migration years 2000-2008. Smolts are estimated at upper dam (or release for Carson hatchery); adults are enumerated at BOA. The NPCC (2009) 2-6% SAR objective or the minimum 2% SAR for listed wild populations is shown for reference. 128 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Upper Columbia River Overall SARs Raymond (1988) estimated pre-harvest SARs for upper Columbia River (above PRD) spring Chinook and steelhead, 1962-1984 smolt migration years. Estimated SARs for both species were somewhat lower than those in the Snake River during the 1960s. Raymond’s smolt indices in the upper Columbia were subject to several assumptions, however, with greater uncertainty in the SAR estimates compared to the Snake River. The CSS will explore incorporating Raymond’s historic SAR estimates into a long-time series for upper Columbia Chinook and steelhead in future analyses. The estimated overall SARs for Upper Columbia River hatchery spring Chinook were represented by a single hatchery (Leavenworth) during 2000-2008. The geometric mean MCN-to-BOA SARs (without jacks) for Leavenworth hatchery Chinook was 0.48%; SARs did not exceed 2% in any year during 2000-2008 (Table 6.19; Figure 6.6). The overall SARs of hatchery Upper Columbia Chinook were highly correlated with wild and hatchery Chinook SARs from the mid-Columbia (average r = 0.78) and with wild and hatchery Chinook SARs from the Snake River (average r = 0.80) during 2000-2008. % SAR MCN to BOA 4.0 3.0 2.0 1.0 0.0 2000 2001 2002 2003 2004 2005 2006 2007 2008 Migration year 20 21 22 23 24 25 26 27 28 29 30 31 Figure 6.6. Bootstrapped SAR (MCN-to-BOA, without jacks) and upper and lower CI for Leavenworth hatchery Chinook from Upper Columbia region for migration years 2000-2008. The NPCC (2009) minimum 2% SAR for listed wild populations is shown for reference. Comparison of PIT-tag and Run Reconstruction SARs The ISAB/ISRP (2008) review of the CSS Ten-Year Retrospective Report (Schaller et al. 2007), encouraged the CSS to investigate differences, and reasons for any differences, between SARs based on PIT tags and those based on run reconstruction methods. Schaller et al. (2007) found that the NOAA run reconstruction SAR point 129 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 estimates (Williams et al. 2005) were about 19% higher (geometric mean) than those produced by CSS using PIT tags. It was unclear whether a bias existed in either the run reconstruction or PIT tag SARs due, in part, to uncertainties and assumptions in the run reconstruction methods. Knudsen et al. (2009) reported that hatchery Chinook from the Yakima River that were PIT-tagged and coded-wire-tagged returned at a 25% lower rate than fish that were only coded-wire-tagged. The Knudsen study illustrated the potential for PIT tag effects, however, its applicability to other river reaches or populations of fish is unknown (Tuomikoski et al. 2009; DeHart 2009). In the CSS 2009 annual report (Tuomikoski et al. 2009), we compared SARs and estimates of juveniles and associated variance used in the IDFG run reconstruction of Snake River wild spring/summer Chinook at Lower Granite Dam (Copeland et al. 2008) with CSS PIT tag estimates. The run reconstruction and CSS SARs were highly correlated (0.92) during 1996-2004, and both time series indicated SARs were well short of the NPCC (2009) 2-6% SAR objectives (Figure 6.7; Tuomikoski et al. 2009). The IDFG run reconstruction SARs were about 35% higher than CSS PIT-tag SARs. The difference between run reconstruction and PIT tag SARs did not appear to be predominantly due to differences in juvenile abundance estimation methods. Tuomikoski et al. (2009) concluded that estimates of juvenile population abundance derived in CSS, when using the Smolt Monitoring Program (SMP) collection index, were similar to those reported by Copeland et al. (2008). Tuomikoski et al. (2009) also developed a bootstrap variance estimator to account for variation in daily detection probability estimates and collection samples for use with the run reconstruction methods. Run reconstruction v PIT SARs 7.0 6.0 ) 5.0 A G L‐ R 4.0 G L( R 3.0 A S % 2.0 Run Rec. SAR PIT SAR 1.0 0.0 1996 24 25 26 27 28 29 30 1997 1998 1999 2000 2001 2002 2003 2004 Migration year Figure 6.7. IDFG run reconstruction SARs compared to CSS PIT tag SARs and 90% CI, migration years 1996-2004 (Tuomikoski et al. 2009). NPCC (2009) 2-6% SAR objectives for listed wild populations are shown for reference. A key assumption for SARs based on run reconstruction or PIT tag data is that the sources of the data are representative of the larger population (e.g., tagged juveniles or 130 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 age structures collected). In the following section we examined SAR methodologies and developed hypotheses for possible sources of bias in both the PIT tag and RR SARs for Snake River wild Chinook. The potential biases considered below are primarily special cases of this assumption. We identified the following factors that could potentially bias PIT-tag SARs: 1) non-representative tagging; 2) post-tagging mortality; 3) tag loss (shedding, damaged tags); 4) weighting schemes from different passage routes (C0, C1, T0); and 5) adult detection efficiency. The CSS Snake River aggregate groups of wild Chinook and steelhead are not sampled at random locations. The wild Chinook are tagged at locations widely distributed in the Snake Basin upstream of LGR, but tagging sites tend to be where densities are highest and compensatory effects (reduced growth and survival rates) are more likely. CSS wild steelhead tags are less well distributed across the Snake River subbasins than are wild Chinook tags. The CSS hatchery Chinook groups are generally representative of the production groups (within hatchery and year), as are the aggregate hatchery steelhead groups beginning in migration year 2008. Post-tagging mortality is not typically evaluated beyond 24 hours in most field studies, and mortality effects associated with tagging small fish may be delayed until emigration and ocean entry. Tag shedding, damaged tags, and other tag loss have not been thoroughly evaluated in most field studies. Potential for SAR bias from weighting route-specific SARs does not seem likely, especially after the CSS began the pre-assignment of tags into the TWS category in 2006. Finally, adult detection efficiency is high within the FCRPS, however, it can be an issue for SARs measured to tributary traps sites especially when using hand wand equipment (Dehart 2009). We identified the following factors that could potentially bias run reconstruction SARs: 1) wild smolt indices and wild adult indices may incorporate different proportions of adipose-intact hatchery fish; 2) window counts used in the RR are not corrected for fall back or counting period; 3) window counts use length criteria to separate jacks and adults; and 4) age composition estimation errors tend to inflate SARs. The IDFG run reconstruction SARs are based on an estimate of the total yield of natural-origin smolts at LGR (denominator) and an age-structured estimate of total returns to LGR (numerator) (Copeland et al. 2008; 2009). To estimate wild juvenile numbers for the run reconstruction, IDFG researchers have multiplied the SMP daily wild collection indices by the NOAA daily collection efficiency estimates, obtained from the Northwest Fisheries Science Center (Steve Smith, NOAA). The SMP wild collection indices include natural-origin smolts and an unknown number of adipose-intact hatchery smolts, which are not coded-wire-tagged (CWT) and are visually indistinguishable from wild smolts. These unmarked non-CWT hatchery smolts in the SMP wild collection indices are primarily fish that had been mis-clipped during mass marking operations at the hatcheries (typically 1-2% at each hatchery). The mis-clipped fish can inflate the wild SMP index and the extant of that bias depends on the relative numbers of wild and hatchery juveniles and the mis-clip rate each year. For example, assume an SMP wild index of 1,000,000, an SMP hatchery index of 7,000,000 and a mis-clip rate of 1%. In this case, the actual number of hatchery fish would be 7,070,707 [=(7,000,000)/(0.99)] and 70,707 mis-clipped hatchery fish would be misclassified as wild. The wild index (1,000,000) would inflate the actual wild (929,293) population in this case by 7.6%. If the mis-clip rate were 2% in the above example, then 142,857 mis-clipped hatchery fish 131 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 would be misclassified as wild, for an inflation factor of 16.7%. For a given mis-clip rate, the inflation factors would increase as the wild smolt index decreased relative to the hatchery smolt index. The IDFG has used LGR window counts of adipose intact Chinook for the run reconstruction SAR estimates since the 1998 run year, which, like the wild smolt indices, also contain un-clipped hatchery fish (T. Copeland and P. Kennedy, IDFG, personal communication). If the inflation factor for the wild adult index is the same as for the wild smolt index, the RR SARs would be unbiased (by this factor). SAR bias could occur if differential survival between wild and hatchery groups led to a different inflation factor in the numerator and denominator of SARs, and/or if different criteria were used to identify wild index smolts and adults. Different proportions of adipose intact hatchery fish between smolt and adult indices are likely in the pre-2006 RR data sets (T. Copeland and P. Kennedy personal communication). Since 2006, adult size composition has been sampled at the Lower Granite trap rather than with video equipment. It may be fruitful in future analyses to focus on comparisons of CSS and RR SARs for these more recent years. A second potential bias in RR SARs is the use of window counts, which are not corrected for fall back or counting period. Any unaccounted fall back would positively bias the window count. Not expanding for counting period would negatively bias the window count. These two errors should tend to counterbalance, but we cannot be sure of the degree of compensation. Trap data collected since 2006 and PIT tag data might be used to help identify re-ascensions, but fall backs that go elsewhere will be difficult to detect in either data set. RR SARs could also contain bias because window counts have used length criteria to separate jacks and adults. This could have a discernable effect on RR SARs for adult sample years computed from U.S. v. Oregon Technical Advisory Committee (TAC) data (1998-2007) (T. Copeland and P. Kennedy personal communication). In the future, PIT tag data and trap samples could be analyzed to assess the potential for bias from use of length criteria in window counts. Finally, age composition estimation errors may inflate RR SARs. Age composition errors tend to misclassify some recruits from dominant year classes into weaker year classes, inflating average SARs (Copeland et al. 2007). The RR used length data sampled from video or adult trap sampling at LGR and estimated the proportion ageat-length from carcass samples collected opportunistically on the spawning grounds. Although methods of aging of the sample (fin ray or scale) appear highly accurate, overall age composition could be biased by non-representative, opportunistic sample collection, which emphasize certain populations and miss smaller fish (T. Copeland and P. Kennedy personal communication). Our preliminary conclusion is that there is potential for bias in both the CSS PIT tag and IDFG run reconstruction SAR estimates, although both provide useful, highly correlated estimates. To date a definitive control group has been lacking to quantify the potential post-marking or tag shedding bias in PIT tag SARs. Similarly, it is not yet possible to evaluate the extent of bias in RR SARs. We developed several hypotheses in this report that might help explain the observed differences in SARs between PIT tag and RR methods. Determining the extent and causes of bias ultimately will be important in the synthesis and interpretation of the different survival rate data sets. 132 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 First Year Ocean Survival Rate (S.o1) Estimated first year ocean survival, S.o1, for Snake River wild spring/summer Chinook during 1994-2007 ranged from 0.4% in 2005 to 8.2% in 2000 and the 13-yr geometric mean was 2.2% (Table 6.20). Estimated S.o1 for wild steelhead during 19972007 ranged from 0.6% in 1998 to 8.2% in 1999 and the 9-yr geometric mean was 2.3% (Table 6.20). Over the same 8-yr period as shown for wild steelhead, the geometric mean of S.o1 was 2.5% for Snake River wild spring/summer Chinook, which is nearly 9% higher than that of wild steelhead. In contrast, the geometric mean of first year ocean survival during 1964-1969 was estimated to be 13.4% and 19.9% for Snake River spring/summer Chinook and steelhead, respectively (Petrosky and Schaller 2010). To date, CSS has estimated S.o1 only for Snake River wild Chinook and steelhead, but will explore estimating S.o1 for mid-Columbia and upper Columbia wild Chinook and steelhead in future reports as we develop the relevant time series of SARs and in-river survival rates. The S.o1 calculations are simplified for these regions without juvenile fish transportation. Discussion In summary, it appears that neither Snake River wild spring/summer Chinook or wild steelhead wild populations are consistently meeting the NPCC 2-6% SAR objective. Geometric mean SARs (LGR-to-GRA) were 0.82% and 1.41% for PIT tagged wild Chinook and steelhead, respectively. Although Snake River hatchery Chinook exhibited a generally more positive response to transportation and relatively lower levels of differential delayed mortality (higher D) than wild populations, annual SARs of Snake River wild and hatchery Chinook were highly correlated across years. In view of this high correlation, continuing the CSS time series of hatchery SARs will be important to augment wild Chinook SAR information following future years of low escapements, in addition to providing valuable management information for the specific hatcheries. The trend in SARs across years for Snake River hatchery spring/summer Chinook are similar to those for the aggregate wild Chinook population in smolt migration years 1997-2008 suggesting similar factors influence their survival during the smolt migration and the estuary and ocean life stages. There were differences among Chinook hatcheries such as Dworshak NFH, which showed generally poorer SARs within years than Rapid River, McCall and Imnaha hatcheries; conversely, the McCall and Imnaha hatcheries typically had among the highest SARs within a year. Reasons for the observed lack of correlation between Snake River wild and hatchery steelhead SARs during 1997-2007 are unknown, but may be related to the opportunistic nature of assembling aggregate hatchery steelhead groups from various monitoring programs for those years. However, there appears to be a moderate correlation between wild Chinook and wild steelhead SARs. More representative tagging for Snake River steelhead hatcheries began in coordination with LSRCP and IPC in migration year 2008. Future implementation of the CSS study design and analysis for hatchery steelhead should allow for evaluation of any disparity among groups (e.g., 133 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 among facilities or A-run vs. B-run) to help craft appropriate weightings for aggregate hatchery steelhead SARs. The first juvenile migration year with sufficient numbers of PIT-tagged fish to estimate SARs for Snake River hatchery sockeye is 2009. CSS plans to begin reporting the time series of sockeye SARs in the 2011 annual report. Mid-Columbia River wild spring Chinook populations, as represented by the John Day River aggregate group, have recently experienced SARs relatively close to the range of the NPCC 2-6% SAR objective. The geometric mean SAR (JDA-to-BOA) for John Day wild Chinook was 3.7% during 2000-2008 and all but one annual SAR exceeded the 2% minimum. CSS has begun a time series of wild steelhead SARs for the John Day River, with the one-salt adults from the 2008 migration returning at a rate of 6.7%. Mid-Columbia River hatchery spring Chinook (Carson and Cle Elum) SARs have varied by year and hatchery during 2000-2008. SARs for Carson hatchery were less than those for Cle Elum hatchery; SARs for both hatcheries were consistently less than those for John Day wild Chinook. Although differing in magnitude, SARs were highly correlated among wild and hatchery Chinook stocks within the mid-Columbia Region. The CSS has begun to establish a time series of SARs for Upper Columbia River wild spring Chinook and steelhead, with PIT tagging in the Wenatchee, Entiat, and Methow rivers in 2009. Leavenworth hatchery spring Chinook SARs were highly correlated with wild and hatchery Chinook stocks from both the mid-Columbia and Snake regions. PIT tag SARs of Snake River wild spring/summer Chinook were highly correlated with IDFG run reconstruction SARs, with both time series indicating SARs were well short of the NPCC 2-6% SAR objective. The run reconstruction SARs were about 35% higher than PIT-tag SARs. We developed several hypotheses in this report that might help explain the observed differences in SARs between PIT tag and run reconstruction methods. Our preliminary conclusion is that there is potential for bias in both the CSS PIT tag and IDFG run reconstruction SAR estimates, although both provide useful, highly correlated estimates. The difference in SARs between run reconstruction and PIT tag SARs did not appear to be primarily due to juvenile abundance estimates. To date a definitive control group has been lacking to quantify the potential bias from postmarking mortality or tag loss in PIT tag SARs. Determining the extent and causes of bias ultimately will be important in the synthesis and interpretation of the different survival rate data sets. Several studies should yield additional insight into the question of PIT tag effects on SARs in the near future. The USFWS (in collaboration with the CSS oversight committee) is working towards implementing a basin-wide independent PIT-tag bias study in an effort to evaluate and test the repeatability of Knudsen et al. (2009) results. Double tagging experiments are currently being planned for Carson Hatchery and other Columbia River hatcheries, Also, as result of the LSRCP and CSS cooperative tagging and other monitoring, researchers anticipate being able to estimate with relative precision returns of PIT tagged and untagged McCall hatchery summer Chinook to the South Fork Salmon River (J. Cassinelli, IDFG, personal communication). The accounting would include estimates of adult survival from LGR to the South Fork Salmon River, Tribal and non-Tribal harvest within the subbasin and numbers of hatchery fish that drop out to spawn below the hatchery weir. 134 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 CSS studies have found that the SAR and first year ocean survival rates for these populations were strongly related to both ocean conditions and seaward migration conditions through the FCRPS (Schaller et al. 2007; Petrosky and Schaller 2010). Parameters estimated in CSS, including in-river survival, transport proportions and D, allow for partitioning of the SARs to estimate first year ocean survival, S.o1. The NPCC (2009) highlighted the need for identifying the effects of ocean conditions on anadromous fish survival so that this information can be used to evaluate and adjust inland actions. The NPCC recognized that a better understanding of the conditions salmon face in the ocean can suggest which factors will be most critical to survival, and thus provide data as to which actions taken inland will provide the greatest benefit in terms of improving the likelihood that Columbia River Basin salmon can survive varying ocean conditions (NPCC 2009). The time series of SARs and S.o1 can then be used to evaluate ocean and smolt migration factors that may influence ocean survival of Snake River and upper Columbia salmon and steelhead as called for in the Fish and Wildlife Program (NPCC 2009). Additional CSS related work to date (evaluating PIT tag survival rate information within season), found positive covariation in mortality rates between the two species: 1) during freshwater outmigration as smolts through a series of hydropower dams and reservoirs; 2) during the period of post-hydrosystem, estuarine/marine residence through adult return; and 3) during the overall life-cycle from smolt outmigration through adult return, suggesting that shared environmental factors are influencing mortality rates of both species. In addition, evidence of positive covariation in mortality rates between the freshwater and subsequent marine-adult life stage for each species, suggests that factors affecting mortality in freshwater partially affect mortality during the marine-adult life stage. This work, along with the findings in Schaller et al. (2007) and Petrosky and Schaller (2010), have illuminated a promising line of inquiry for upcoming CSS study direction. We plan to explore evaluating the correlation for SARs among the regions. In addition, we plan to evaluate which environmental and river management variables best explain the variation in survival rates for the various life stages (eg. SAR , S.o1, and S.r) and by regional grouping. This study direction is consistent with NPCC direction and past recommendations from the ISAB. 135 1 Supporting Tables Table 6.1 Estimated overall LGR-to-GRA SARs for the Snake River basin (above LGR) PIT-tagged wild spring/summer Chinook aggregate, 1994 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 2 3 4 5 6 Smolts arriving LGR A LGR-to-GRA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-GRA with Jacks Non-parametric CI SAR Estimate 90% LL 90%UL 1994 15,260 0.43 0.22 0.66 0.47 0.24 0.70 1995 20,206 0.35 0.20 0.52 0.35 0.19 0.52 1996 7,868 0.42 0.06 0.84 0.43 0.06 0.85 1997 2,898 1.73 0.97 2.68 1.78 0.99 2.73 1998 17,363 1.21 0.82 1.64 1.25 0.84 1.70 1999 33,662 2.39 1.89 2.94 2.55 2.03 3.09 2000 25,053 1.71 1.22 2.24 1.72 1.25 2.20 2001 22,415 1.27 0.54 2.11 1.45 0.70 2.32 2002 23,356 0.92 0.75 1.10 1.04 0.83 1.24 2003 31,093 0.34 0.26 0.41 0.34 0.26 0.42 2004 32,546 0.52 0.43 0.63 0.54 0.44 0.64 2005 35,216 0.22 0.17 0.28 0.24 0.18 0.30 2006 15,274 0.70 0.58 0.81 0.75 0.63 0.87 2007 14,919 0.98 TBD TBD 1.09 TBD TBD 2008 B 13,604 2.26 TBD TBD 2.78 TBD TBD 0.80 0.86 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through July 26, 2010 NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. Table 6.2 Estimated overall LGR-to-BOA SARs for the Snake River basin (above LGR) PIT-tagged wild spring/summer Chinook aggregate, 2000 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 7 8 9 10 Smolts arriving LGR A LGR-to-BOA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-BOA with Jacks Non-parametric CI SAR Estimate 90% LL 90%UL 2000 25,053 2.60 1.95 3.28 2.69 2.01 3.39 2001 22,415 1.81 0.90 2.89 1.99 1.09 2.99 2002 23,356 1.14 0.94 1.35 1.29 1.07 1.52 2003 31,093 0.34 0.26 0.42 0.34 0.27 0.42 2004 32,546 0.68 0.56 0.80 0.69 0.58 0.80 2005 35,216 0.29 0.23 0.36 0.30 0.23 0.37 2006 15,274 0.84 0.73 0.98 0.90 0.77 1.03 2007 14,919 1.13 0.98 1.27 1.24 1.09 1.39 2008 B 13,604 1.95 1.75 2.15 2.54 2.33 2.78 0.95 1.04 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through May 28, 2010 NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. 136 1 Table 6.3 Estimated overall LGR-to-GRA SARs for PIT-tagged Dworshak hatchery spring Chinook, 1997 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 2 3 4 5 6 Smolts arriving LGR A LGR-to-GRA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-GRA with Jacks Non-parametric CI SAR Estimate 90% LL 90%UL 1997 8,175 0.62 0.44 0.81 0.63 0.46 0.84 1998 40,218 1.00 0.90 1.11 1.14 1.04 1.25 1999 40,804 1.18 1.05 1.32 1.22 1.08 1.36 2000 39,412 1.00 0.92 1.10 1.01 0.92 1.12 2001 41,251 0.36 0.29 0.43 0.42 0.35 0.49 2002 45,233 0.57 0.48 0.65 0.72 0.63 0.81 2003 38,612 0.24 0.19 0.29 0.25 0.20 0.30 2004 45,505 0.29 0.23 0.34 0.29 0.23 0.34 2005 43,042 0.19 0.15 0.24 0.20 0.16 0.25 2006 29,511 0.35 0.29 0.42 0.46 0.40 0.52 2007 28,511 0.36 0.31 0.42 0.46 0.40 0.53 2008 B 25,643 0.53 TBD TBD 0.80 TBD TBD 0.48 0.54 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through July 26, 2010 NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. Table 6.4 Estimated overall LGR-to-BOA SARs for PIT-tagged Dworshak hatchery spring Chinook, 2000 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 7 8 9 10 11 12 13 14 15 16 17 Smolts arriving LGR A LGR-to-BOA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-BOA with Jacks C Non-parametric CI SAR Estimate 90% LL 90%UL 2000 39,412 1.58 1.45 1.70 ---2001 41,251 0.44 0.37 0.51 ---2002 45,233 0.75 0.66 0.85 ---2003 38,612 0.31 0.26 0.37 ---2004 45,505 0.53 0.46 0.61 ---2005 43,042 0.29 0.24 0.35 ---2006 29,511 0.56 0.49 0.64 ---2007 28,511 0.49 0.42 0.56 ---2008 B 25,643 0.89 0.80 0.99 ---0.57 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through May 28, 2010 C Will be completed for future reports NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. 137 Table 6.5 Estimated overall LGR-to-GRA SARs for PIT-tagged Rapid River hatchery spring Chinook, 1997 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 1 2 3 4 5 Smolts arriving LGR A LGR-to-GRA without Jacks SAR Non-parametric CI Estimate 90% LL 90%UL LGR-to-GRA with Jacks SAR Non-parametric CI Estimate 90% LL 90%UL 1997 15,765 0.65 0.52 0.79 0.65 0.52 0.78 1998 32,148 1.88 1.71 2.07 1.98 1.80 2.18 1999 35,895 2.91 2.69 3.13 3.04 2.82 3.25 2000 35,194 1.94 1.79 2.08 1.96 1.82 2.10 2001 38,026 1.06 0.94 1.18 1.17 1.04 1.29 2002 41,471 0.90 0.79 1.01 1.07 0.95 1.19 2003 37,911 0.24 0.19 0.29 0.31 0.26 0.37 2004 36,178 0.34 0.28 0.41 0.36 0.29 0.42 2005 38,231 0.25 0.20 0.31 0.27 0.22 0.33 2006 26,349 0.50 0.43 0.58 0.60 0.52 0.68 2007 25,798 0.34 0.28 0.40 0.47 0.40 0.54 2008 B 29,071 1.23 TBD TBD 1.89 TBD TBD 0.74 0.86 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through July 26, 2010 NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. Table 6.6 Estimated overall LGR-to-BOA SARs for PIT-tagged Rapid River hatchery spring Chinook, 2000 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 6 7 8 9 10 11 12 13 Smolts arriving LGR A LGR-to-BOA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-BOA with Jacks C Non-parametric CI SAR Estimate 90% LL 90%UL 2000 35,194 2.71 2.53 2.87 ---2001 38,026 1.38 1.24 1.52 ---2002 41,471 1.06 0.94 1.18 ---2003 37,911 0.34 0.28 0.41 ---2004 36,178 0.43 0.36 0.50 ---2005 38,231 0.31 0.26 0.37 ---2006 26,349 0.74 0.66 0.83 ---2007 25,798 0.48 0.41 0.55 ---2008 B 29,071 1.71 1.58 1.84 ---0.78 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through May 28, 2010 C Will be completed for future reports NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. 138 1 Table 6.7 Estimated overall LGR-to-GRA SARs for PIT-tagged Catherine Creek hatchery spring Chinook, 2001 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 2 3 4 5 6 Smolts arriving LGR A LGR-to-GRA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-GRA with Jacks Non-parametric CI SAR Estimate 90% LL 90%UL 2001 10,885 0.22 0.12 0.34 0.26 0.14 0.40 2002 8,435 0.77 0.56 1.00 1.00 0.76 1.28 2003 7,202 0.31 0.20 0.43 0.40 0.25 0.54 2004 5,348 0.36 0.20 0.54 0.40 0.22 0.58 2005 4,848 0.40 0.22 0.60 0.48 0.27 0.68 2006 4,289 0.49 0.32 0.69 0.61 0.41 0.81 2007 4,695 0.43 0.27 0.59 0.83 0.62 1.04 2008 B 6,605 2.04 TBD TBD 2.87 TBD TBD 0.49 0.64 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through July 26, 2010 NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. Table 6.8 Estimated overall LGR-to-BOA SARs for PIT-tagged Catherine Creek hatchery spring Chinook, 2001 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 7 8 9 10 11 12 13 14 15 Smolts arriving LGR A LGR-to-BOA without Jacks SAR Non-parametric CI Estimate LGR-to-BOA with Jacks C SAR Non-parametric CI Estimate 2001 10,885 0.37 0.23 0.51 ---2002 8,435 1.11 0.83 1.41 ---2003 7,202 0.35 0.22 0.50 ---2004 5,348 0.44 0.25 0.64 ---2005 4,848 0.50 0.30 0.73 ---2006 4,289 0.79 0.58 1.03 ---2007 4,695 0.53 0.36 0.71 ---2008 B 6,605 2.60 2.28 2.93 ---0.66 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through May 28, 2010 C Will be completed for future reports NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. 139 1 Table 6.9 Estimated overall LGR-to-GRA SARs for PIT-tagged McCall hatchery summer Chinook, 1997 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 2 3 4 5 6 Smolts arriving LGR A LGR-to-GRA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-GRA with Jacks Non-parametric CI SAR Estimate 90% LL 90%UL 1997 22,381 1.31 1.15 1.46 1.41 1.25 1.58 1998 27,812 2.50 2.28 2.73 3.07 2.80 3.32 1999 31,571 3.26 3.02 3.49 3.73 3.48 4.02 2000 31,825 3.12 2.92 3.33 3.63 3.41 3.84 2001 36,784 1.20 1.07 1.34 1.55 1.39 1.71 2002 32,599 1.34 1.19 1.50 1.82 1.64 2.00 2003 43,144 0.68 0.60 0.76 1.00 0.91 1.09 2004 40,150 0.39 0.33 0.46 0.47 0.40 0.55 2005 43,229 0.57 0.50 0.64 0.61 0.54 0.69 2006 21,794 1.06 0.95 1.18 1.27 1.15 1.41 2007 19,082 0.89 0.77 1.01 1.42 1.28 1.56 2008 B 21,044 1.01 TBD TBD 2.24 TBD TBD 1.19 1.55 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through July 26, 2010 NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. Table 6.10 Estimated overall LGR-to-BOA SARs for PIT-tagged McCall hatchery summer Chinook, 2000 to 2008. SARs are calculated with and without jacks. Juvenile Migration year 7 8 9 10 11 12 13 14 Smolts arriving LGR A LGR-to-BOA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-BOA with Jacks C Non-parametric CI SAR Estimate 90% LL 90%UL 2000 31,825 3.76 3.53 3.99 ---2001 36,784 1.46 1.30 1.62 ---2002 32,599 1.72 1.54 1.91 ---2003 43,144 0.81 0.72 0.89 ---2004 40,150 0.52 0.44 0.61 ---2005 43,229 0.68 0.60 0.77 ---2006 21,794 1.29 1.15 1.42 ---2007 19,082 1.10 0.97 1.23 ---2008 B 21,044 TBD TBD TBD ---1.18 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through May 28, 2010 – too early to report C Will be completed for future reports NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. 140 1 Table 6.11 Estimated overall LGR-to-GRA SARs for PIT-tagged Imnaha hatchery summer Chinook, 1997 to 2008. SARs are calculated with and without jacks. Juvenile Migration Year 2 3 4 5 6 Smolts arriving LGR A LGR-to-GRA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-GRA with Jacks Non-parametric CI SAR Estimate 90% LL 90%UL 1997 8,254 0.98 0.76 1.23 1.35 1.10 1.64 1998 13,577 0.81 0.63 1.00 1.46 1.20 1.73 1999 13,244 2.41 2.09 2.74 3.20 2.82 3.57 2000 14,267 2.89 2.63 3.15 3.99 3.66 4.31 2001 15,650 0.61 0.48 0.77 0.98 0.80 1.17 2002 13,962 0.68 0.52 0.85 1.02 0.83 1.23 2003 14,948 0.53 0.42 0.65 1.26 1.08 1.43 2004 12,867 0.36 0.25 0.46 0.45 0.33 0.58 2005 11,172 0.27 0.17 0.37 0.32 0.23 0.43 2006 8,753 0.80 0.64 0.96 1.12 0.95 1.30 2007 9,596 0.66 0.53 0.80 1.38 1.18 1.59 2008 B 10,148 1.64 TBD TBD 4.39 TBD TBD 0.83 1.33 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through July 26, 2010 NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. Table 6.12 Estimated overall LGR-to-BOA SARs for PIT-tagged Imnaha hatchery summer Chinook, 2000 to 2008. SARs are calculated with and without jacks. Juvenile Migration Year 7 8 9 10 11 12 13 14 15 Smolts arriving LGR A LGR-to-BOA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-BOA with Jacks C Non-parametric CI SAR Estimate 90% LL 90%UL 2000 14,267 3.61 3.29 3.93 ---2001 15,650 0.81 0.66 0.99 ---2002 13,962 0.92 0.73 1.13 ---2003 14,948 0.71 0.58 0.84 ---2004 12,867 0.57 0.43 0.71 ---2005 11,172 0.35 0.24 0.46 ---2006 8,753 0.99 0.83 1.18 ---2007 9,596 0.84 0.69 1.00 ---2008 B 10,148 TBD TBD TBD ---0.87 Geometric Mean A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with 2-salt returns through May 28, 2010 – too early to report C Will be completed for future reports NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. 141 1 Table 6.13 Estimated overall LGR-to-GRA and LGR-to-BOA SARs for Snake River basin (above LGR) PIT-tagged wild summer steelhead aggregate, 1997 to 2008. Juvenile Migration year 2 3 4 Smolts arriving LGR A SAR Estimate LGR-to-GRA Non-parametric CI 90% LL 90%UL SAR Estimate LGR-to-BOA Non-parametric CI 90% LL 90%UL 1997 3,830 1.16 0.37 2.12 ---1998 7,109 0.30 0.07 0.66 ---1999 8,820 2.84 1.68 4.19 ---2000 13,609 2.66 1.62 3.72 2.99 1.88 4.17 2001 12,929 2.47 0.97 4.49 3.98 1.91 6.21 2002 13,378 2.14 1.24 3.21 2.60 1.47 3.82 2003 12,926 1.57 1.22 1.94 1.86 1.47 2.25 2004 13,263 0.85 0.63 1.08 1.31 1.03 1.58 2005 15,124 0.80 0.60 1.01 1.02 0.81 1.26 2006 5,431 1.14 0.91 1.40 1.92 1.59 2.21 2007 7,083 2.56 2.25 2.88 3.29 2.93 3.66 2008 B 5,730 1.40 1.17 1.67 1.87 1.56 2.16 Geometric Mean 1.41 2.17 (through 2007) A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with only 1-salt returns available. Table 6.14 Estimated overall LGR-to-GRA and LGR-to-BOA SARs for Snake River basin (above LGR) PIT-tagged hatchery summer steelhead aggregates, 1997 to 2008. Juvenile Migration year 5 6 7 8 9 10 11 12 Subbasin and run type Smolts arriving LGR A LGR-to-GRA Non-parametric CI SAR Estimate 90% LL 90%UL LGR-to-BOA D 90% CI SAR Est. LL UL 1997 all 24,710 0.39 0.22 0.59 ---1998 all 23,507 0.56 0.30 0.85 ---1999 all 27,193 0.92 0.59 1.30 ---2000 all 24,565 1.89 1.18 2.70 ---2001 all 20,877 0.92 0.24 1.74 ---2002 all 20,681 0.95 0.40 1.72 ---2003 all 21,400 1.46 1.24 1.68 ---2004 all 17,082 2.08 1.15 3.19 ---2005 all 19,640 1.83 1.17 2.55 ---2006 all 13,473 1.96 1.32 2.62 ---2007 all 21,828 1.64 1.37 1.92 ---2008 B GRN-A 16,858 3.66 3.40 3.94 ---2008 B IMN-A 12,468 4.01 3.68 4.35 ---SAL-A 17,429 4.41 4.15 4.69 ---2008 B C 2008 B SAL-B 18,369 ------2008 B CLW-B 24,718 ------1.18 Geometric Mean (through 2007) A Estimated population of tagged study fish alive to LGR tailrace (includes fish detected at the dam and those estimated to pass undetected) using total tag release through 2005 and TWS tags beginning in 2006. B Incomplete with only 1-salt returns – too early to report for B-run stocks without 2-salts next year. C Excludes 1,200 PIT-tagged Niagara Springs hatchery steelhead due to their low numbers and exclusive return-to-river routing at transportation sites. D Will be completed for future reports. 142 1 Table 6.15 Estimated overall JDA-to-BOA SARs for PIT-tagged John Day River basin wild spring Chinook, 2000 to 2008. SARs are calculated with and without jacks. Juvenile Migration Year 2 3 4 5 6 7 8 Smolts arriving JDA A JDA-to-BOA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL JDA-to-BOA with Jacks C Non-parametric CI SAR Estimate 90% LL 90%UL 2000 1,255 11.39 9.58 13.33 ---2001 2,721 3.90 3.24 4.50 ---2002 2,555 3.72 3.01 4.43 ---2003 4,203 2.93 2.46 3.42 ---2004 2,755 3.19 2.50 4.01 ---2005 3,907 1.82 1.46 2.20 ---2006 2,188 2.10 1.56 2.70 ---2007 2,606 4.53 3.77 5.30 ---2008 B 2,929 5.02 4.22 5.82 ---3.71 Geometric Mean A Estimated population of tagged study fish alive to JDA tailrace (includes fish detected at the dam and those estimated to pass undetected). B Incomplete with 2-salt returns through May 28, 2010 C Will be completed for future reports NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. Table 6.16 Estimated overall BON-to-BOA and release-to-BOA SARs for PIT-tagged Carson hatchery spring Chinook, 2000 to 2008. SARs are calculated without jacks D. Juvenile Migration Year 9 10 11 12 13 14 Smolts arriving BON A BON-to-BOA without Jacks 90% CI SAR Estimate LL UL Smolts released REL-to-BOA without Jacks 90% CI SAR Estimate LL UL 2000 12,945 3.30 2.71 3.91 14,992 2.85 2.62 2001 12,506 1.78 1.50 2.05 14,978 1.49 1.32 2002 12,349 1.22 0.94 1.54 14,983 1.01 0.88 2003 12,709 0.27 0.19 0.36 14,983 0.23 0.17 2004 NA C ------14,973 0.62 0.51 2005 14,053 0.32 0.23 0.42 14,958 0.30 0.23 2006 10,509 0.60 0.45 0.77 14,971 0.42 0.33 2007 NA C ------14,973 0.56 0.46 2008 B 11,681 1.75 1.48 2.05 14,884 1.37 1.22 0.94 0.73 Geometric Mean A Estimated population of tagged study fish alive to BON tailrace (includes fish detected at the dam and those estimated to pass undetected). B Incomplete with 2-salt returns through May 28, 2010 C Not calculated since estimated release-to-BON reach survival rates >1. D SARs with jacks will be completed for future reports NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. 143 3.07 1.65 1.14 0.29 0.73 0.37 0.51 0.67 1.53 1 Table 6.17 Estimated overall MCN-to-BOA SARs for PIT-tagged Cle Elm hatchery spring Chinook, 2000 to 2008. SARs are calculated with and without jacks. Juvenile Migration Year 2 3 4 5 6 7 8 Smolts arriving MCN A MCN-to-BOA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL MCN-to-BOA with Jacks C Non-parametric CI SAR Estimate 90% LL 90%UL 2000 13,794 3.81 3.47 4.14 ---2001 9,228 0.28 0.19 0.37 ---2002 11,728 1.37 1.18 1.56 ---2003 11,962 0.59 0.48 0.71 ---2004 7,982 1.54 1.31 1.79 ---2005 5,784 0.66 0.48 0.83 ---2006 10,141 1.25 1.07 1.44 ---2007 12,675 1.01 0.87 1.16 ---2008 B 11,837 2.75 2.48 3.01 ---1.13 Geometric Mean A Estimated population of tagged study fish alive to MCN tailrace (includes fish detected at the dam and those estimated to pass undetected). B Incomplete with 2-salt returns through May 28, 2010 C Will be completed for future reports NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. Table 6.18 Estimated overall JDA-to-BOA SARs for PIT-tagged John Day River basin wild summer steelhead, 2004 to 2008. Juvenile Migration Year 9 10 11 12 13 Smolts arriving JDA A SAR Estimate JDA-to-BOA Non-parametric CI 90% LL 90%UL 2004 B ----2005 B ----2006 B ----2007 B ----2008 C 3,220 6.68 5.74 7.66 3.71 Geometric Mean A Estimated population of tagged study fish alive to JDA tailrace (includes fish detected at the dam and those estimated to pass undetected). B PIT-tagged wild steelhead for juvenile migration years 2004 to 2007 will be completed for future reports C Incomplete with 1-salt returns only 144 1 Table 6.19 Estimated overall MCN-to-BOA SARs for PIT-tagged Leavenworth hatchery spring Chinook, 2000 to 2008. SARs are calculated with and without jacks. Juvenile Migration Year 2 3 4 5 6 Smolts arriving MCN A MCN-to-BOA without Jacks Non-parametric CI SAR Estimate 90% LL 90%UL MCN-to-BOA with Jacks C Non-parametric CI SAR Estimate 90% LL 90%UL 2000 4,360 1.83 1.48 2.22 ---2001 3,808 0.24 0.13 0.38 ---2002 178,609 0.36 0.34 0.39 ---2003 153,594 0.43 0.40 0.45 ---2004 104,754 0.34 0.31 0.37 ---2005 7,880 0.09 0.04 0.15 ---2006 8,183 0.89 0.72 1.09 ---2007 8,882 0.46 0.34 0.59 ---2008 B 9,118 1.73 1.49 1.97 ---0.48 Geometric Mean A Estimated population of tagged study fish alive to MCN tailrace (includes fish detected at the dam and those estimated to pass undetected). B Incomplete with 2-salt returns through May 28, 2010 C Will be completed for future reports NOTE: 2007 and 2008 SARs and CI will be re-run in September with final 2010 returns. 145 1 Table 6.20. Estimation of first year ocean survival rates, S.o1, for Snake River wild spring/summer Chinook 1994-2007, and wild steelhead, 1997-2007 based on CSS parameter estimates for SAR, inriver survival (SR), proportion transported (pT) and D. Migration Year 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Geometric Mean SAR CSS SAR lgr to lgr-lgr In-river Prop. mouth Survival Transported System excluding Columbia harvest (SR) (pT) D Survival PIT-tagged Wild Spring/Summer Chinook Aggregate S.o1 0.20 0.41 0.44 0.51 0.61 0.59 0.48 0.23 0.61 0.60 0.40 0.48 0.57 TBD 0.863 0.805 0.706 0.572 0.815 0.863 0.709 0.989 0.709 0.694 0.929 0.926 0.667 TBD 0.360 0.420 0.920 0.400 0.550 0.720 0.320 2.160 0.440 0.680 0.450 1.070 0.540 TBD 0.33 0.41 0.77 0.44 0.55 0.69 0.36 2.10 0.48 0.65 0.44 1.01 0.54 TBD 0.004 0.004 0.004 0.017 0.012 0.024 0.017 0.013 0.009 0.003 0.005 0.002 0.008 0.010 0.005 0.004 0.004 0.019 0.014 0.029 0.020 0.015 0.011 0.004 0.006 0.003 0.009 0.013 0.014 0.009 0.006 0.043 0.026 0.042 0.054 0.007 0.024 0.006 0.013 0.003 0.017 TBD 0.448 0.779 0.596 0.588 0.008 0.009 0.022 PIT-tagged Wild Summer Steelhead Aggregate 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Geometric Mean 0.52 0.54 0.45 0.30 0.038 0.52 0.37 0.18 0.27 TBD TBD 0.715 0.892 0.869 0.846 0.992 0.675 0.723 0.974 0.930 TBD TBD 1.034 1.034 1.034 1.034 1.034 1.034 1.034 1.034 1.034 TBD TBD 0.87 0.96 0.94 0.90 1.01 0.85 0.83 0.99 0.96 TBD TBD 0.012 0.003 0.028 0.027 0.025 0.021 0.016 0.009 0.008 0.011 0.026 0.017 0.005 0.043 0.037 0.034 0.028 0.021 0.012 0.011 0.020 0.034 0.020 0.005 0.045 0.041 0.034 0.033 0.025 0.012 0.011 TBD TBD 0.288 0.839 1.034 0.923 0.014 0.020 0.023 2 146 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Chapter 7 Effects of Bypass Systems on Juvenile Travel Times and SARs Introduction Smolt collection or bypass systems are currently in place at seven of the eight dams on the lower Snake and Columbia rivers. Although some studies have found that smolt survival estimates through bypass systems are nearly as high as through spillways (Muir et al. 2001), there are concerns regarding the effects of bypass systems on migration delay (Beeman and Maule 2001), delayed mortality (Budy et al. 2002) and SARs (Tuomikoski et al. 2009). If smolts that migrate through bypass systems express migration delay or delayed mortality, then the direct survival rates that have been estimated for smolts utilizing bypass systems (e.g., Muir et al. 2001) or SARs that are conditioned upon bypass detections may not be providing a comprehensive and accurate picture of the effects of the various migration routes on migration or survival rates. A better understanding of the indirect and delayed effects of passage through bypass systems would assist hydrosystem and fishery managers in developing hydrosystem operations that could assist in the recovery of ESA-listed stocks. Toward the objective of improving understanding of the effects of bypass systems on Chinook salmon and steelhead, we conducted three sets of analyses. In the first set of analyses, we evaluated the effects of bypass systems on fish travel time from Lower Granite Dam to Bonneville Dam. This work evaluates whether fish that are detected in the bypass systems at Little Goose, Lower Monumental, McNary or John Day dams have shorter or longer travel times relative to fish that are not detected at those dams (i.e., passing through spillway or turbine routes). In the second set of analyses, we evaluated the effects of bypass history on SARs from Bonneville Dam outmigration as a juvenile until Bonneville Dam return as an adult. We were interested in evaluating two primary management-oriented questions with these data. First, we were interested in evaluating whether multiple bypass experiences negatively affected post-Bonneville Dam SARs. This question addresses one of the key hypotheses presented in Budy et al. (2002), that previous migration history affects levels of delayed mortality. Support for the Budy et al. (2002) hypothesis would be indicated by significant reductions in post-Bonneville Dam SARs as the number of bypass experiences increased. If so, then hydrosystem management strategies that reduce or minimize the number of bypass experiences would be expected to increase post-BON SARs. The second question we were interested in was whether there was evidence that bypass at particular dams was more harmful than others. If there are indications that a bypass experience at a particular dam reduces post-BON SARs, then those dams could targeted for reducing the proportion of fish that experience the bypass system at that dam through increasing spillway percentages and/or structural modifications to the spillway (e.g., RSWs or TSWs). In the third set of analyses, we use techniques developed in Chapter 5 of Tuomikoski et al. (2009) to explore the hypothesis that cumulative effects of bypassing smolts at dams results in increased mortality expressed in SARs. We perform random effects meta-analysis to estimate the summary distributions of the ratio of SAR(C1) to SAR(C0) from annual estimates of this ratio, for wild Chinook and steelhead. 147 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Effects of bypass systems on juvenile fish travel time Methods Data for these analyses consisted of hatchery and wild spring/summer Chinook salmon and steelhead PIT-tagged and released upriver of Lower Granite Dam (LGR), along with juveniles that were PIT-tagged and released at LGR during juvenile migration years 1998-2009. Fish used in this analysis were restricted to those that were detected at both LGR and Bonneville (BON) dams during the out-migration year, thus all were known to have survived and their travel time from LGR to BON were estimable given their detection dates at each location. We then queried and recorded their detection histories (i.e., whether they were detected or not) at each intermediate dam with a juvenile bypass detection system, which included Little Goose Dam (LGS), Lower Monumental Dam (LMN), McNary Dam (MCN) and John Day Dam (JDA). The number of observations for each migration year, rearing type and species is provided in Table 7.1. Table 7.1 Number of wild and hatchery Chinook (CHN) and steelhead (STH) detected at both LGR and BON for use in travel time analysis over migration years 1998-2009. 18 19 20 21 22 23 24 25 26 27 28 29 Year 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Total wild CHN 1,311 2,626 1,051 1,473 2,009 4,414 1,232 1,127 1,267 1,819 1,048 1,933 21,310 hat. CHN 4,409 8,185 1,157 3,788 1,021 1,840 1,729 3,597 10,141 4,593 4,313 7,319 52,092 wild STH 995 1,598 6,755 202 2,618 2,381 140 134 1,005 993 1,258 1,633 19,712 hat. STH 3,196 8,512 2,374 470 1,935 635 305 330 1,321 2,002 4,496 8,604 34,180 Multiple linear regression was used to evaluate whether bypass systems had an effect on LGR-BON fish travel time (FTT). Previous CSS analyses (e.g., Tuomikoski et al. 2009) showed that median fish travel times for weekly release cohorts exhibit substantial within-season variability. To account for this, we fit third-order polynomial functions of Julian day of release at LGR. To evaluate if bypass systems affected FTT, indicator variables were added to the model, with 1 denoting bypass detection at a dam and 0 denoting non-detection at a dam. The initial model took the form FTT 0 1 D 2 D 2 3 D 3 4 I LGS 5 I LMN 6 I MCN 7 I JDA (Eqn. 7.1) where D is the Julian day of release at LGR, and I LGS , I LMN , I MCN , and I JDA are indicator variables taking the value 1 when a fish is detected in a bypass system at a 148 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 particular dam and 0 when a fish is not detected in a bypass system at that same dam. Consistent with other researchers examining the distribution of data on individual FTT (Zabel and Anderson 1997), the distributions were positively skewed, often with long right tails. Thus the untransformed data were not likely to meet the linear regression model requirement of normally-distributed residuals. Therefore Box-Cox power transformations were conducted using the model in Equation 7.1 to determine an appropriate transformation for achieving normally-distributed residuals. The Box-Cox transformations indicated that an inverse-transformation was appropriate for the majority of the years (1998-2009), species (Chinook or steelhead) and rearing types (hatchery or wild) considered. Each year, species and rearing type was analyzed separately using Equation 7.1, but with the dependent variable being 1/FTT. Estimates of 4 , 5 , 6 and 7 were used to determine the statistical significance (α = 0.05) of the bypass systems on FTT at LGS, LMN, MCN and JDA, respectively. Estimates of mean delay (or acceleration) at each dam of bypassed fish relative to undetected fish was computed by subtracting the back-transformed predictions for FTT of non-detected fish from the backtransformed predictions for FTT of fish detected in the bypass system. Positive values of mean delay indicated that bypassed fish had longer FTT than fish that were not bypassed, and negative values of mean delay indicated that bypassed fish had shorter FTT than fish that were not bypassed. Results There were 48 year-dam combinations for each species and rearing type (Table 7.2, Figures 7.1 and 7.2). For wild Chinook, there were 32 year-dam combinations indicating significant bypass delay (67%), one year-dam combination indicating bypass acceleration (2%) and the remaining 15 year-dam combinations (31%) indicated no significant difference between bypassed and non-detected fish. Similarly, for hatchery Chinook, there were 32 year-dam combinations indicating significant bypass delay (67%), two year-dam combinations indicating bypass acceleration (4%) and the remaining 14 year-dam combinations (29%) indicated no significant difference between bypassed and non-detected fish. For wild steelhead, there were 11 year-dam combinations indicating significant bypass delay (23%), 8 year-dam combinations indicating bypass acceleration (17%) and the remaining 29 year-dam combinations (60%) indicated no significant difference between bypassed and non-detected fish. Similarly, for hatchery steelhead, there were 16 year-dam combinations indicating significant bypass delay (33%), 7 year-dam combinations indicating bypass acceleration (15%) and the remaining 25 year-dam combinations (52%) indicated no significant difference between bypassed and non-detected fish. The results indicated similar patterns for hatchery and wild rearing types of yeardam combinations with significant bypass delay or acceleration (Table 7.2). Cases of significant bypass delay for Chinook ranged from 0.13 d to 5.32 d and averaged 0.69 d. Cases of significant bypass delay for steelhead ranged from 0.19 d to 2.71 d and averaged 0.73 d. The three cases of significant bypass acceleration for Chinook ranged from 0.20 d to 1.10 d and averaged 0.70 d. The 15 cases of significant bypass relative acceleration for steelhead ranged from -0.35 d to -7.55 d and averaged -2.38 d. 149 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 The year-dam combinations that indicated bypass acceleration compared to nondetected fish occurred more often and generally had a higher magnitude during 2001 (Table 7.2), which was a year when most voluntary spill was eliminated at LGS, LMN, MCN and JDA. Additional year-dam combinations where voluntary spill was eliminated included LMN in 2002 for spilling basin repairs and at both LGS and LMN in 2004 and 2005 for maximized transportation operations. Discussion The results of this work are consistent with Beeman and Maule (2001), who measured gatewell and collection channel residence times for radio-tagged juvenile Chinook and steelhead at McNary Dam. They found that median residence times in the gatewell and collection channel were 8.9 h and 2.3 minutes for Chinook, and 3.2 h and 28 minutes for steelhead. We found that the amount of delay associated with bypass systems is approximately 0.7 d, or 16.8 h. Combining our results with those of Beeman and Maule (2001), indicates that there is some amount of forebay delay occurring for both species prior to fish entering the gatewells. It is possible that steelhead may resist the sounding required to enter the gatewells. Plumb et al. (2001) found that steelhead reduce their migration speeds relative to water velocities as they approached Lower Granite Dam, with substantial numbers of fish traveling upriver when water velocities were low or when spill was not provided. Although both species in our analysis demonstrated more cases of migration delay associated with those fish that were bypassed, there were fewer cases of significant migration delay for steelhead than Chinook. If steelhead indeed resist sounding, then one plausible mechanism for this difference may be that the delay associated with bypassed fish is less than the delay associated with fish that pass through the turbines, which require deeper sounding than gatewells. Our results lend some support to this hypothesis. Cases of relative bypass acceleration compared to non-detected fish mainly occurred in 2001, when involuntary spill was terminated at most dams. Under these conditions, steelhead that were bypassed had significantly lower FTTs than steelhead that were not detected in six of the eight cases for hatchery and wild steelhead. The 2001 results suggest that steelhead passing through the turbines (the only non-bypass route available) took significantly longer to migrate than steelhead passing through the bypass systems. This analysis suggests that caution is warranted when interpreting route-specific survival rate estimates. The route-specific survival estimates are defined from the upriver face of a dam to the point of the paired release in the tailrace (Skalski et al. 2002), and survival is similarly defined in paired hose-release studies into individual passage routes (e.g., Muir et al. 2001). These two designs do not account for the amount of delay and mortality that occurs in the forebay. Further, it is not possible to separate the mortality that occurs for smolts destined for each passage route. Because of these issues, the high route-specific survival rates that have been estimated for bypass systems (in addition to the other route-specific estimates) may be providing a misleading picture of the consequences of total passage survival from the forebay, through the individual passage routes, and through the tailrace. Our results indicate that there is a significant amount of migration delay associated with bypass systems, which extends the amount of time smolts are exposed to predators and therefore may also reduce forebay survival rates. 150 1 2 3 4 5 Because of these issues, we believe that caution is warranted when interpreting routespecific survival rate estimates. Other mark-recapture designs that focus on total reach survival using PIT-tags (Burnham et al. 1987, Skalski et al. 1998) are less likely to suffer from these design issues and may better reflect true survival rates for smolt populations. Table 7.2 Estimates of bypass delay (d) for wild and hatchery spring/summer Chinook salmon and steelhead smolts at Little Goose Dam (LGS), Lower Monumental Dam (LMN), McNary Dam (MCN) and John Day Dam (JDA) over migration years 1998-2009. Positive values (black shading) indicate cases where bypassed fish had statistically significant increases in travel time relative to fish not detected at the dam. Negative values (grey shading) indicate cases where bypassed fish had statistically significant reductions in travel time relative to fish not detected at the dam. Blank cells indicate differences that were not statistically significant at the α = 0.05 level. 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Year 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 wild Chinook LGS LMN MCN 0.5 1.0 0.4 0.3 0.8 0.5 0.9 ‐1.1 0.6 0.5 0.6 0.5 0.7 0.4 2.1 0.3 0.4 0.4 0.5 0.5 0.5 0.7 0.3 0.6 1.2 0.4 0.7 JDA 0.7 0.4 1.9 0.4 0.4 0.6 hatchery Chinook LGS LMN MCN JDA 0.7 1.0 ‐0.2 0.9 0.3 0.2 0.4 0.3 0.4 ‐0.8 2.2 1.1 0.6 0.6 0.4 0.9 5.3 0.5 0.3 0.7 0.1 0.1 0.3 0.5 0.7 0.4 0.5 0.6 0.7 0.7 0.5 0.5 0.4 0.5 151 wild steelhead LGS LMN MCN JDA ‐0.4 ‐0.4 0.6 0.4 0.2 ‐4.6 ‐3.0 ‐7.5 ‐0.4 ‐0.4 0.4 0.6 1.1 hatchery steelhead LGS LMN MCN JDA 0.3 0.3 0.4 0.4 ‐0.6 ‐3.6 ‐4.8 ‐6.1 ‐2.1 1.3 2.7 0.7 0.6 0.3 ‐0.7 0.8 0.6 ‐0.4 0.7 0.6 0.4 0.8 1.3 0.4 0.7 0.7 ‐0.7 0.9 1.3 Wild CHN 3.0 2.0 1.0 Bypass delay (d) 0.0 1997 1999 2001 2003 2005 2007 2009 ‐1.0 LGS ‐2.0 LMN MCN JDA Hatch. CHN 6 5 4 Bypass delay (d) 3 2 1 0 1997 ‐1 1 2 3 4 5 6 7 8 9 10 11 1999 2001 2003 2005 LGS ‐2 2007 LMN 2009 MCN JDA Figure 7.1 Estimates of bypass delay for wild (top panel) and hatchery (bottom panel) spring/summer Chinook salmon smolts at Little Goose Dam (LGS, diamonds), Lower Monumental Dam (LMN, squares), McNary Dam (MCN, triangles) and John Day Dam (JDA, circles) over migration years 1998-2009. Positive values indicate cases where bypassed fish had statistically significant increases in travel time relative to fish not detected at the dam. Negative values indicate cases where bypassed fish had statistically significant reductions in travel time relative to fish not detected at the dam. 152 Wild STH 2 Bypass delay (d) 0 1997 1999 2001 2003 2005 2007 2009 ‐2 ‐4 ‐6 LGS ‐8 LMN MCN JDA Hatch. STH 4 2 Bypass delay (d) 0 1997 ‐2 1999 2001 2003 2005 2007 2009 ‐4 ‐6 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 ‐8 LGS LMN MCN JDA Figure 7.2 Estimates of bypass delay for wild (top panel) and hatchery (bottom panel) steelhead smolts at Little Goose Dam (LGS, diamonds), Lower Monumental Dam (LMN, squares), McNary Dam (MCN, triangles) and John Day Dam (JDA, circles) over migration years 1998-2009. Positive values indicate cases where bypassed fish had statistically significant increases in travel time relative to fish not detected at the dam. Negative values indicate cases where bypassed fish had statistically significant reductions in travel time relative to fish not detected at the dam. Effects of bypass systems on post-Bonneville Dam survival Methods The data for this analysis consisted of spring/summer Chinook and steelhead of both hatchery and wild origin that were PIT-tagged and released upriver of Lower Granite Dam (LGR) during migration years 2000-2008 and subsequently detected at Bonneville Dam. Detection histories were determined for each smolt at dams with collection or bypass systems with juvenile PIT-tag detection capabilities, which included LGR, Little Goose Dam (LGS), Lower Monumental Dam (LMN), McNary Dam (MCN), John Day Dam (JDA) and Bonneville Dam (BON). At Bonneville Dam, juvenile smolts could be detected within the juvenile bypass system or within the corner collector (2006 – present). Within the full dataset, we queried for records of smolts that were detected at BON, either in the juvenile bypass system or the corner collector. These fish were 153 1 2 3 4 5 6 7 known to have survived up through detection at BON, and each had an associated bypass history at upriver dams, with the number of previous bypass experiences ranging from zero to five. We then determined whether each smolt that was detected at BON returned to BON as an adult. Thus, these data provide an estimate of the SAR from BON as a smolt to BON as an adult. The number of smolts and adults used in the analysis for each year is provided in Table 7.3. Table 7.3 Number of hatchery and wild Chinook and steelhead detected at Bonneville Dam, the number of adult returns from those smolts, and the corresponding BON-BON SAR across smolt migration years 2000-2008. 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Year 2000 2001 2002 2003 2004 2005 2006 2007 2008 Total CHN smolts CHN adults 10,437 382 7,120 22 15,388 231 15,657 123 4,187 24 5,238 14 11,058 128 18,141 208 7,041 252 94,267 1,384 SAR 3.66% 0.31% 1.50% 0.79% 0.57% 0.27% 1.16% 1.15% 3.58% STH smolts 2,957 456 3,339 3,812 280 299 1,199 2,386 12,117 26,845 STH adults 83 3 87 52 8 1 29 73 477 813 SAR 2.81% 0.66% 2.61% 1.36% 2.86% 0.33% 2.42% 3.06% 3.94% We used logistic regression techniques (Hosmer and Lemeshow 2000) within an information-theoretic framework (Burnham and Anderson 2002) to address these two questions for Chinook and steelhead. The dependent variable was the probability of adult return at BON. We considered five a priori models for characterizing variability in the probability of adult return. Model 1 consisted of year effects and an additive effect of hatchery rearing type to examine whether hatchery smolts consistently had lower or higher post-BON SARs. Model 2 was a year-by-rearing type interaction model, which allowed for annual differences between post-BON SARs for hatchery and wild smolts. Models 3, 4 and 5 also included the year-by-rearing type interaction, but differed in the way bypass effects were modeled. Model 3 included a variable that was the total number of bypass experiences (“TOT.byp”) at upriver dams. Model 4 included one variable that was the number of bypass experiences at Snake River dams (LGR, LGS and LMN, “SNK.byp”) and another variable that was the number of bypass experiences at Columbia River dams (MCN and JDA, “COL.byp”). Model 4 thus examines whether there is a difference in the severity of bypass experiences between dams in the two river systems. Model 5 included indicator variables denoting the location of bypass (“byp.location”) at upriver dams to determine whether bypass systems at individual dams were more or less severe than others. Each model was fit for each species and we recorded the Akaike’s Information Criterion (AIC) for each model, with lower AIC values indicating better fitting models. We then calculated information-theoretic summary statistics, including 154 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 1 AIC differences, ∆i = AICi – AICmin, the individual model likelihoods = exp i , 2 and the model probabilities (Burnham and Anderson 2002): 1 exp i 2 . (Eqn. 7.2) wi 3 1 exp i 2 i 1 The best degree of fit was mainly determined by lowest AIC, but the relative probabilities of each model, given the data and the set of five models considered were also used. The model probabilities provide the weight of evidence in favor of model i being the best model for the data, given that one of the five models is the Kullback-Leibler best model in the set (Burnham and Anderson 2002:75). Results For Chinook, Model 1 indicated that post-BON SARs for hatchery smolts averaged 25% less than wild smolts, and this effect was statistically significant (P < 0.00001). For steelhead, there was a tendency that post-BON SARs for hatchery smolts were lower than wild smolts (estimated effect was an 11% reduction for hatchery smolts relative to wild smolts), but the effect was not statistically significant (P = 0.168). However, for both Chinook and steelhead, Model 2 with the year-by-rearing type interactions had substantially lower AIC values than Model 1 (14 points for CHN and 11 points for STH, Table 7.4), indicating that the relative difference between hatchery and wild smolts varied across years with wild smolts having higher, lower or equivalent post-BON SARs compared to hatchery smolts (Table 7.4, Figure 7.3). Incorporating bypass effects (Models 3, 4 and 5) further reduced AIC values compared to Model 2 (without bypass effects) for both species (Table 7.4), indicating that bypass history was important for characterizing variation in post-BON SARs. For Chinook, Model 3 with the total number of bypass experiences had the lowest AIC value, followed by Model 4. The Model 3 estimates for Chinook showed a 10% reduction in post-BON SARs per bypass experience at upriver dams (P = 0.0001, Table 7.5). For steelhead, Model 4, which differentiated the number of bypasses at Snake River dams versus the number of bypasses at Columbia River dams, had the lowest AIC value. The Model 4 estimates for steelhead showed a 6% reduction in post-BON SAR per bypass experience at Snake River dams (P = 0.21, Table 7.6) and a 22% reduction in post-BON SAR per bypass experience at Columbia River dams (P = 0.0006, Table 7.6). The Model 5 results, which estimate dam-specific bypass effects, showed similar patterns to the lowest-AIC models of each species (Table 7.7). For Chinook, estimates of bypass effects were similar across Snake and Columbia river dams (Table 7.7). For steelhead, estimates of bypass effects were much more severe at MCN and JDA dams than they were at LGR, LGS or LMN (Table 7.8). 155 Table 7.4 Information-theoretic summary statistics for the five models considered for Chinook and steelhead. Model species parameters AIC ∆ AIC model lik. model prob. 1: year + hatch. CHN 10 13740.38 26.81 0.00 0.00 2: year*hatch. CHN 18 13726.53 12.96 0.00 0.00 3: year*hatch. + TOT.byp CHN 19 13713.57 0.00 1.00 0.70 4: year*hatch. + SNK.byp + COL.byp CHN 20 13715.52 1.95 0.38 0.26 5: year*hatch. + byp.location CHN 22 13719.74 6.17 0.05 0.03 1 2 3 4 5 6 7 8 9 10 11 12 13 1: year + hatch. 2: year*hatch. 3: year*hatch. + TOT.byp 4: year*hatch. + SNK.byp + COL.byp 5: year*hatch. + byp.location STH STH STH STH STH 10 18 19 20 22 7200.41 7189.55 7181.51 7178.72 7182.32 21.69 10.83 2.79 0.00 3.60 0.00 0.00 0.25 1.00 0.17 0.00 0.00 0.17 0.71 0.12 Figure 7.3 Model 3 estimates of post-BON SARs for wild (blue squares) and hatchery (yellow circles) Chinook salmon smolts with zero bypass experiences at upriver dams (left panel), and Model 4 estimates of post-BON SARs for wild (blue squares) and hatchery (yellow circles) steelhead smolts with zero bypass experiences at upriver dams (right panel). Error bars represent 95% confidence intervals on the mean post-BON SAR. Hatchery steelhead in 2001 and wild steelhead in 2005 had zero adult returns, precluding the estimation of confidence intervals for those cases. 156 1 Table 7.5 Model 3 logistic regression parameter estimates, standard errors, z values and p-values for Chinook. 2 Variable Estimate Std. Error z value TOT.byp -0.117 0.031 -3.8 2000 wild -2.756 0.092 -30.1 2000 hatchery -3.397 0.070 -48.6 2001 wild -4.818 0.332 -14.5 2001 hatchery -5.747 0.302 -19.0 2002 wild -3.637 0.145 -25.0 2002 hatchery -4.146 0.082 -50.5 2003 wild -5.087 0.247 -20.6 2003 hatchery -4.660 0.100 -46.5 2004 wild -4.468 0.325 -13.7 2004 hatchery -5.163 0.273 -18.9 2005 wild -6.736 1.003 -6.7 2005 hatchery -5.521 0.284 -19.5 2006 wild -3.987 0.249 -16.0 2006 hatchery -4.345 0.101 -42.9 2007 wild -3.896 0.185 -21.0 2007 hatchery -4.400 0.081 -54.5 2008 wild -3.198 0.141 -22.7 2008 hatchery -3.171 0.078 -40.9 157 Pr(> |z| ) 1.29E-04 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 1.88E-11 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 1 Table 7.6 Model 4 logistic regression parameter estimates, standard errors, z values and p-values for steelhead. The high standard errors for hatchery steelhead in 2001 and wild steelhead in 2005 are due to the absence of adult returns from those releases. 2 Variable Estimate Std. Error SNK.byp -0.063 0.050 COL.byp -0.268 0.078 2000 wild -3.000 0.150 2000 hatchery -3.985 0.219 2001 wild -3.793 0.595 2001 hatchery -17.259 245.684 2002 wild -3.478 0.170 2002 hatchery -3.485 0.154 2003 wild -4.265 0.249 2003 hatchery -4.113 0.175 2004 wild -4.460 1.009 2004 hatchery -3.024 0.395 2005 wild -17.301 364.979 2005 hatchery -4.961 1.008 2006 wild -3.895 0.458 2006 hatchery -3.359 0.220 2007 wild -3.135 0.186 2007 hatchery -3.489 0.160 2008 wild -3.133 0.162 2008 hatchery -3.093 0.057 158 z value -1.3 -3.4 -20.0 -18.2 -6.4 -0.1 -20.4 -22.7 -17.1 -23.5 -4.4 -7.7 0.0 -4.9 -8.5 -15.3 -16.8 -21.7 -19.4 -54.0 Pr(> |z| ) 2.07E-01 5.92E-04 2.00E-16 2.00E-16 1.80E-10 9.44E-01 2.00E-16 2.00E-16 2.00E-16 2.00E-16 9.77E-06 1.80E-14 9.62E-01 8.65E-07 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 2.00E-16 1 Table 7.7 Logistic regression parameter estimates, standard errors, z values and p-values for bypass effects of Models 3, 4 and 5 for Chinook. 2 3 Model 3 Variable Estimate Std. Error TOT.byp -0.117 0.031 z value Pr(> |z| ) -3.8 0.0001 Model 4 Variable Estimate Std. Error SNK.byp -0.111 0.041 COL.byp -0.126 0.048 z value Pr(> |z| ) -2.7 0.0062 -2.6 0.0087 Model 5 Variable Estimate Std. Error LGR.byp -0.088 0.073 LGS.byp -0.185 0.072 LMN.byp -0.055 0.073 MCN.byp -0.114 0.061 JDA.byp -0.143 0.078 z value Pr(> |z| ) -1.2 0.2285 -2.6 0.0101 -0.8 0.4528 -1.9 0.0626 -1.8 0.0650 Table 7.8 Logistic regression parameter estimates, standard errors, z values and p-values for bypass effects of Models 3, 4 and 5 for steelhead. 4 5 6 7 8 9 Model 3 Variable Estimate Std. Error TOT.byp -0.127 0.041 z value Pr(> |z| ) -3.1 0.0018 Model 4 Variable Estimate Std. Error SNK.byp -0.063 0.050 COL.byp -0.268 0.078 z value Pr(> |z| ) -1.3 0.2074 -3.4 0.0006 Model 5 Variable Estimate Std. Error LGR.byp -0.101 0.089 LGS.byp -0.116 0.079 LMN.byp 0.061 0.094 MCN.byp -0.249 0.110 JDA.byp -0.291 0.116 z value Pr(> |z| ) -1.1 0.2549 -1.5 0.1445 0.7 0.5148 -2.3 0.0233 -2.5 0.0116 159 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Discussion The results of this analysis lends support to the Budy et al. (2002) hypothesis that the cumulative effects of migration conditions through the hydrosystem affect levels of delayed mortality expressed in post-BON SARs of both Chinook and steelhead. This support comes from Models 3-5, which contained variables measuring the location and number of previous bypass experiences at upriver dams, being the best fitting models based on AIC values among the five models considered for Chinook and steelhead. For both species, there was evidence that as the number of bypass experiences increased, post-BON SARs decreased. As for location of bypass, we found little evidence that postBON SARs of Chinook depended on their location of bypass. However, we found evidence that bypass location affected post-BON SARs of steelhead, with McNary and John Day dam bypass histories having a stronger detrimental effect than bypass at LGR, LGS or LMN. The results from this analysis indicate that SARs conditioned upon bypass detections should be viewed with some caution. Our results showed that post-BON SARs for bypassed smolts are lower than post-BON SARs for non-detected smolts. Therefore analyses that utilize detected smolts as the starting population for calculating SARs are likely to be biased low relative to smolts that are not detected at that same dam. Furthermore, we have provided evidence that subsequent downstream bypass experiences may further influence the resulting SARs, with smolts that pass undetected through the dams expected to have higher SARs than those smolts that are bypassed one or more times. The life-cycle modeling conducted by Kareiva et al. (2000) and Wilson (2003) indicated that improving survival in the estuary and ocean was critical for achieving recovery objectives of ESA-listed Snake River spring/summer Chinook. The results for our work indicate that bypass experiences upriver may be one factor that is lowering post-BON SARs of Chinook and steelhead. Therefore management strategies that reduce the number of bypass experiences through increasing spill proportions or structural modifications to spillways (e.g., RSWs or TSWs), especially at McNary and John Day dams (in the case of steelhead), could assist in increasing post-BON survival rates. Additionally, researchers have found that Chinook and steelhead smolts arriving at BON earlier in the season tend to have higher SARs than smolts that arrive later in the season (Scheuerell et al. 2009). Given the results in the first section of this chapter, increased spillway passage and reduced bypass passage is expected to reduce migration delay, which would allow for Chinook and steelhead smolts to arrive at the estuary faster and in better condition than under a management strategy that maintains higher levels of passage through bypass systems. Meta- Analysis comparing SARs of C1 and C0 wild Chinook and steelhead In this section, techniques developed in Chapter 5 of Tuomikoski et al. (2009) are used to explore the hypothesis that cumulative effects of bypass at dams can result in mortality expressed in SARs. A random effects meta-analysis is performed to estimate summary distributions of the ratio of SAR(C1) to SAR(C0) from annual estimates of this ratio, for wild Chinook and steelhead. 160 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 The C0 group is the estimated number of fish that passed LGR, LGS, and LMN undetected; the C1 group is made up of fish that were detected at least once at any of LGR, LGS, or LMN, and not transported. Fish in either group may or may not be detected at some later facility (i.e. MCN, JDA, BON, TWX). If the SARs of the two groups are equal, we should expect estimates of SAR(C1)/SAR(C0) to center around 1; if SAR(C1) is generally higher, the ratio should on average be > 1; and if SAR(C1) is generally lower, we the ratio should on average be < 1. Methods Annual estimates of SARs for Chinook from 1994-2006 migration years, and for steelhead from 1997 -2006, were used in the analysis. The SAR(C0) and SAR(C1) were estimated using E[C0] and E[C1] estimated smolt numbers (below) and returning adults (without Jacks for Chinook) for each category, and expressed as a differential for comparison (i.e., SAR(C1)/SAR(C0)). Data from migration year 2007 were not used, due to the delayed start of smolt transportation in that and subsequent years, and the desire to avoid non-stationarity. Migration year 2006 is included here because although transportation was delayed, the delay was shorter than in subsequent years, and the portion of the run transported was similar to preceding years, as shown in the following table: Year Lower Granite Dam (LGR) Little Goose Dam (LGS) Lower Monumental Dam (LMN) 19942005 2006 2007 March 25 April 1 April 1 April 20 May 1 April 24 May 8 April 28 May 11 The equations for estimating the expected number of PIT-tagged smolts in C0 and C1 categories are as follows with known numbers removed (dj) at each dam (j) expressed in LGR-equivalents (j = 2 for LGR, 3 for LGS, 4 for LMN, 5 for MCN, 6 for JDA, and 7 for BON): where E[C0] = R1•S1•(1-P2)•(1-P3)•(1-P4) – d0 [7.1] d5.0 d 6.0 d 7.0 d0 S 2 * S3 * S 4 S 2 * S3 * S 4 * S5 S 2 * S3 * S 4 * S 5 * S 6 where E[C1] = R1•S1•[P2 + (1-P2)•P3 + (1-P2)•(1-P3)•P4] – [(d2 + d3 /S2 + d4 /(S2•S3) + d1] d5.1 d 6.1 d 7.1 d1 S 2 * S3 * S 4 S 2 * S3 * S 4 * S5 S 2 * S3 * S 4 * S5 * S 6 161 [7.2] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 In years prior to 2006, PIT-tagged smolts were being bypassed at a relative similar rate across the full season, since transportation occurred across the full season. But beginning in 2006, the start of transportation was delayed, causing a higher portion of C1 fish to migrate earlier in the season, when conditions are favorable (and hence survival on average would be expected to be greater than over the whole season). Also beginning in 2006, the CSS began to pre-assign PIT-tagged smolts into two groups (Groups T and R) as described in Chapter 4. Prior to that year a single aggregate of PIT-tagged wild Chinook and another aggregate of wild steelhead were created for each migration year. The 2006 pre-assigned smolts in Group R follow the return-to-river operations at each of the collector dams over the entire migration season, and therefore provide a more consistent comparison with the years prior to 2006. Therefore, for migration year 2006, a combination of Groups T and R, comparable to the single release group of past years was used for the C0 estimate, while Group R fish was used for C1 estimate (i.e., E[C1] for Group R). This allows the comparison between C1 and C0 smolts to reflect just the impacts of how these smolts passed the Snake River collector dams, since any underlying but unmeasured seasonal trend for in-river survival, if it occurs in 2006, would then apply equally to the C0 and C1 groups. Formulas used to estimate heterogeneity (between-year) variance, summary means, confidence intervals of the mean, and prediction intervals are provided in Tuomikoski et al. (2009). Except as noted below, sample variances used for each year were derived from bootstrap outputs. For wild steelhead, there were no C0 adults detected returning from juvenile migration year 2004. Since the point estimate and sampling variance of SAR(C1)/SAR(C0) are therefore undefined, that year was omitted from the analysis. Data from migration year 2001 were also omitted from the analysis, even though three steelhead adults without juvenile detections at the transport projects were later detected as adults. This was because there was substantial residualism of steelhead that year and these “C0” fish may have passed raceways undetected during a computer outage in mid-May at LGR (Berggren et al. 2005a). The resultant point estimate of SAR(C1)/SAR(C0) was anomalously low (one fifth of the next lowest annual point estimate), and the data from 2001 would have been highly influential in the summary distribution. For wild Chinook, only one C0 adult each was detected returning from juvenile migration years 2001 and 2005. Consequently, for those years the theoretical variance of the natural logarithm of the ratio of two survival rates was used as the estimate of sampling variance, as described in Tuomikoski et al. (2009). Due to the computer outage, the one “C0” Chinook adult return from the 2001 migration may actually have been transported. However, the point estimate was neither the lowest nor the highest of the series, and due to the large sampling variance and consequently tiny weight it receives in estimating the summary effect (Figure 1) it has little influence, and so was retained in the estimation. Results Forest plots are commonly used in meta-analysis to present resulting summary mean distributions and show the influence of estimates from each study on the summary. Figures 7.1 and 7.2 are forest plots showing the summary mean distribution of SAR(C1)/SAR(C0), along with contribution and precision of each annual estimate, for 162 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 wild Chinook and wild steelhead, respectively. Figure 7.3 shows the 90% confidence interval of the summary mean and the 90% prediction interval for both Chinook and steelhead in box and whisker format. The confidence intervals of the means of SAR(C1)/SAR(C0) for both species are entirely below one, indicating a significant mortality effect, at 5% α level, from bypass at one or more collector facilities. Although the mean of the Chinook summary distribution is higher than the mean for steelhead, the confidence interval of the Chinook mean is much smaller, indicating greater confidence in the conclusion of a bypass mortality effect. The wider steelhead confidence interval results from fewer PIT-tagged smolts per year and fewer years of data. Figure 7.1 Forest plot of SAR(C1)/SAR(C0) for wild Chinook. Squares are centered on the point estimate for each year; horizontal lines display the 90% confidence interval for each estimate. X-axis is logarithmic, with vertical line at SAR(C1)/SAR(C0) = 1. The area of each box is proportional to the weight it receives in estimating the summary effect. The diamond is the summary estimate and has its vertical points lined up with the summary mean estimate; the width of the diamond shows the 90% confidence interval of the mean. 163 1 2 3 4 5 6 7 8 Figure 7.2 Forest plot of SAR(C1)/SAR(C0) for wild steelhead. Squares are centered on the point estimate for each year; horizontal lines display the 90% confidence interval for each estimate. X-axis is logarithmic, with vertical line at SAR(C1)/SAR(C0) = 1. The area of each box is proportional to the weight it receives in estimating the summary effect. The diamond is the summary estimate and has its vertical points lined up with the summary mean estimate; the width of the diamond shows the 90% confidence interval of the mean. 10.0 1.0 C1/C0 0.1 9 10 11 12 Chinook Steelhead Figure 7.3 Summary mean SAR(C1)/SAR(C0) (center lines), 90% CIs of summary mean (boxes), and 90% prediction limits of summary (whiskers). 164 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Discussion The summary distributions here show the limitations of relying on SARs of C1 fish as surrogates for the pre-2006 untagged in-river migrating population, for purposes of estimating TIR and D. Due either to limited numbers of C0 adult returns or indeterminate passage history of returnees, or both, on occasion annual TIRs and Ds intended to reflect the experience of untagged fish are estimated for some years using either a mix of C1 and C0 fish or only C1 fish. In addition, estimates of within-season blocks of TIR and D based on passage timing at LGR or another dam are made to examine trends in these quantities over the migration season. These SAR ratios are necessarily calculated using only C1 fish, since a dam passage date is available only for fish which are detected (or released) at that dam. Whatever the reason for the substitution, it seems that TIRs and Ds using C1 fish will tend to substantially overestimate the true values that would be obtained using C0 fish. This caveat should be clearly stated anytime this substitution is employed by investigators. Results presented here should be interpreted with some cautions in mind. A basic assumption of meta-analysis is that the individual studies summarized are statistically independent from each other. Since adjacent year classes of Chinook or steelhead overlap during their ocean residence, and fish from two or more year classes can make the upstream adult migration in the same year, a particular year’s environmental conditions can influence the survival of multiple cohorts. Conversely, given the general strong dependence of marine survival on conditions during the first critical months at sea (e.g., Pearcy 1992), adjacent year classes should experience somewhat different environmental conditions (temporally and spatially). The degree of dependence between adjacent year classes of SARs is difficult to estimate. However, only the ratios of SARs are analyzed here; lack of independence in the absolute SARs does not necessarily imply similar dependence in the ratios of SARs. To the extent that lack of independence is a problem in this analysis, the confidence intervals shown here will be too narrow, with increased probability of a Type 1 error [see Discussion in Tuomikoski et al. (2009), Chapter 5]. The underestimation of the confidence interval of the mean would have to be very large to affect the conclusion of a bypass mortality effect for Chinook. However, given the proximity of the upper confidence limit of the steelhead mean to 1, the potential underestimation of the interval suggests the finding of bypass mortality for steelhead should be considered provisional. The above analysis looked at PIT-tagged wild Chinook and wild steelhead; however, there is further evidence that of a reduced SAR of bypassed fish across the PITtagged hatchery Chinook and steelhead groups analyzed in Chapter 4. For the migration years with uniquely estimated SAR(C0) between 1997 and 2007 (excluding 2001 and 2005 for Chinook and 2001, 2004, and 2005 for steelhead because an estimate for C0 fish was not possible without including C1 fish), the average SAR(C1) was less than the average SAR(C0). This implies that the process of being “collected” to the point necessary for PIT-tag detection and subsequently migrating in-river compromised smoltto-adult survival (Figure 7.4). This reduction in smolt viability is potentially due to the stress, injury, and/or disease factors associated with the “collection” process (Budy et al. 2002; Marmorek et al. 2004). Improving SARs for bypassed and transported salmonid smolts would appear 165 1 2 3 4 5 6 7 8 9 10 11 12 13 to require a reduction in the detrimental effects of the “collection” process. Alternatively, operations could be implemented which reduced the proportion of in-river migrating fish that experience the collection process, such as increasing spill and/or flow levels, thereby increasing the SARs of in-river migrants through reducing the number of collection and bypass experiences of smolts. Figure 7.4 Comparison of average SAR(C0) and SAR(C1) for the PIT-tagged PIT-tagged hatchery steelhead aggregate [HST] and the four CSS PIT-tagged hatchery Chinook groups with longest time series (Rapid River [RAPH], Dworshak [DWOR], McCall [MCCA] and Imnaha [IMNA]) for years noted in text. Years 2006 and 2007 use SAR(C1) values of Group R fish to eliminate the effect of starting transportation later in those two years compared to the earlier years being averaged. 166 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 References Beeman, J.W., and A.G. Maule. 2001. Residence times and diel passage distributions of radio-tagged juvenile spring Chinook salmon and steelhead in a gatewell and fish collection channel of a Columbia River dam. North American Journal of Fisheries Management 21:455–463. Berggren, T.J., and M.J. Filardo. 1993. 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Hydrobiologia 609:289-300. 174 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Appendix A Source of PIT-tagged Fish PIT-tagged Wild Chinook Aggregate – Composition by Drainage Table A.1 Number of PIT-tagged wild Chinook parr/smolts from tributaries above Lower Granite Dam (plus Snake River trap) used in the CSS analyses for migration years 1994 to 2009. Clearwater Snake Grande Salmon Imnaha River River trapA Ronde River River River Migr Total Year PIT tags (Rkm 224) (Rkm 225) (Rkm 271) (Rkm 303) (Rkm 308) 1994 49,657 8,292 1,423 8,828 27,725 3,391 1995 74,639 17,605 1,948 12,330 40,609 2,148 1996 21,523 2,246 913 7,079 7,016 4,269 1997 9,781 671 None 3,870 3,543 1,697 1998 33,836 4,681 921 8,644 11,179 8,411 1999 81,493 13,695 3,051 11,240 43,323 10,184 2000 67,841 9,921 1,526 7,706 39,609 9,079 2001 47,775 3,745 29 6,354 23,107 14,540 2002 67,286 14,060 1,077 9,715 36,051 6,428 2003 103,012 15,106 381 14,057 60,261 13,165 2004 99,743 17,214 541 12,104 56,153 13,731 2005 111,152 23,897 318 9,243 67,829 9,865 2006 52,978 8,663 2,639 10,457 30,094 1,125 2007 52,496 3,041 373 9,267 28,561 11,254 2008 47,899 4,477 0 8,316 24,266 10,840 2009 47,880 5,111 0 7,848 26,140 8,781 Average percent of total 15.7% 1.6% 15.2% 54.2% 13.3% A Snake River trap at Lewiston, ID, collects fish originating in Salmon, Imnaha, and Grande Ronde rivers. PIT-tagged Rapid River Hatchery Spring Chinook – Salmon River Drainage Table A.2 Rapid River Hatchery spring Chinook (RAPH) PIT-tagged and released in Salmon River basin specifically for CSS (long time series), 1997 to 2009. Migration Hatchery Fish# / Median Length at PIT Tags PIT Tag Year Release lb Tagging (mm) Released Proportion 1997 85,838 20.5 100 A 40,451 0.4712 1998 896,170 20.3 117 48,336 0.0539 1999 2,847,283 17.9 120 47,812 0.0168 2000 2,462,354 19.2 119 47,747 0.0194 2001 736,601 18.8 118 55,085 0.0748 2002 2,669,476 19.8 122 54,908 0.0206 2003 2,330,557 18.8 119 54,763 0.0235 2004 2,762,058 24.5 (none taken) 51,969 0.0188 2005 2,761,430 19.1 124 51,975 0.0188 2006 2,530,528 19.3 129 51,874 0.0205 2007 2,498,246 20 117 51,759 0.0207 2008 2,493,719 16.7 125 51,689 0.0207 2009 2,503,711 20.0 (none taken) 51,725 0.0207 A Tagged in fall 5 months before release; otherwise tagged in winter/spring 1-3 months before release. 175 1 2 3 4 5 6 7 8 9 10 11 12 13 14 PIT-tagged Dworshak Hatchery Spring Chinook – Clearwater River Drainage Table A.3 Dworshak Hatchery spring Chinook (DWOR) PIT-tagged and released in Clearwater River basin specifically for CSS (long time series), 1997 to 2009. Migration Hatchery Fish# / Median Length at PIT Tags PIT Tag Year Release lb Tagging A (mm) Released Proportion 1997 53,078 12.7 118 14,080 0.2653 1998 973,400 20.9 121 47,703 0.049 1999 1,044,511 21 116 47,845 0.0458 2000 1,017,873 24 112 47,743 0.0469 2001 333,120 19.7 121 55,139 0.1655 2002 1,000,561 20.1 119 54,725 0.0547 2003 1,033,982 21.4 120 54,708 0.0529 2004 1,078,923 20.2 113 51,616 0.0478 2005 1,072,359 19.2 112 51,819 0.0483 2006 1,007,738 20 108 51,900 0.0515 2007 963,211 17.7 114 51,649 0.0536 2008 939,000 23.5 105 49,384 0.0526 2009 1,014,748 21.2 113 50,829 0.0501 A Tagged in winter/spring 1-3 months before release. PIT-tagged McCall Hatchery Summer Chinook – Salmon River Drainage Table A.4 McCall Hatchery summer Chinook (MCCA) PIT-tagged and released in Salmon River basin specifically for CSS (long time series), 1997 to 2009. Migration Hatchery Fish# / Median Length at PIT Tags PIT Tag Year Release lb Tagging A (mm) Released Proportion 1997 238,647 17.1 128 52,652 0.2206 1998 393,872 17.5 126 47,340 0.1202 1999 1,143,083 23.9 117 47,985 0.042 2000 1,039,930 23.3 117 47,705 0.0459 2001 1,076,846 19.4 129 55,124 0.0512 2002 1,022,550 23 122 54,734 0.0535 2003 1,053,660 21.1 121 74,317 0.0705 2004 1,088,810 20.9 (none taken) 71,363 0.0655 2005 1,047,530 20.9 121 71,725 0.0685 2006 1,096,130 18.1 126 51,895 0.0473 2007 1,087,170 19.1 122 51,726 0.0476 2008 1,060,540 19.5 129 51,678 0.0487 2009 1,106,700 21.3 (none taken) 51,495 0.0465 A Tagged in winter/spring 1-3 months before release. 176 1 2 PIT-tagged Imnaha Hatchery Summer Chinook – Imnaha River Drainage 3 4 Table A.5 Imnaha Hatchery summer Chinook (IMNA) PIT-tagged and released in Imnaha River basin specifically for CSS (long time series), 1997 to 2009. Migration Hatchery Fish# / Median Length at PIT Tags PIT Tag Year Release lb Tagging (mm) Released Proportion 1997 50,911 17 122A 13,378 0.2628 1998 93,108 21.1 122A 19,825 0.2129 1999 184,725 18.5 117 19,939 0.1079 2000 179,797 19.1 113 20,819 0.1158 2001 123,014 16 121 20,922 0.1701 2002 303,737 14.1 121 20,920 0.0689 2003 268,426 16.3 123 20,904 0.0779 2004 398,469 26.1 98 20,910 0.0525 2005 435,186 24.5 105 20,917 0.0481 2006 320,752 27.1 105 20,623 0.0643 2007 432,530 21.6 107 20,885 0.0483 2008 348,910 20.3 116 20,760 0.0595 2009 234,963 20.0 110 20,863 0.0888 A Tagged in winter/spring 1-3 months before release; otherwise tagged in fall 5-7 months before release. 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 PIT-tagged Catherine Creek AP Spring Chinook – Grande Ronde River Drainage Table A.6 Catherine Creek Hatchery spring Chinook (CATH) PIT-tagged and released in Grande Ronde River basin specifically for CSS (long time series), 2001 to 2009. Migration Hatchery Fish# / Median Length at PIT Tags PIT Tag Year Release lb Tagging A (mm) Released Proportion 2001 136,833 19.7 117 20,915 0.1529 2002 180,343 18.6 115 20,796 0.1153 2003 105,292 12.8 123 20,628 0.1959 2004 162,614 23.2 109 20,994 0.1291 2005 189,580 25.1 106 20,839 0.1099 2006 68,820 22.7 102 20,958 0.3045 2007 71,268 26.9 102 20,817 0.2921 2008 116,882 17.9 112 20,717 0.1772 2009 138,843 22.7 107 20,840 0.1501 A Tagged in fall 5-7 months before release. PIT-tagged Hatchery Chinook Additions to CSS Table A.7 Additional hatchery spring and summer Chinook PIT-tagged A and released in Grande Ronde River basin with participation with the CSS beginning in 2009. Hatchery Fish# / PIT Tags PIT Tag Release lb Released Proportion Hatchery Stock Clearwater H (CLWH) spring 2,214,144 16.8 68,649 0.0310 Sawtooth H (SAWT) spring 274,644 14.0 18,671 0.0680 Pahsimeroi H (PAHP) summer 870,842 11.3 18,749 0.0215 A No lengths taken at time of tagging 177 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 PIT-tagged Wild Steelhead Aggregate – Composition by Drainage Table A.8 Number of PIT-tagged wild steelhead smolts from tributaries above Lower Granite Dam (plus Snake River trap) used in the CSS analyses for migration years 1997 to 2009. Clearwater Snake Grande Salmon Imnaha River River trapA Ronde River River River Migr Total Year PIT tags (Rkm 224) (Rkm 225) (Rkm 271) (Rkm 303) (Rkm 308) 1997 7,703 5,518 68 248 1,158 711 1998 10,512 4,131 1,032 887 1,683 2,779 1999 15,763 5,095 886 1,628 5,569 2,585 2000 24,254 8,688 1,211 3,618 6,245 4,492 2001 24,487 8,845 867 3,370 7,844 3,561 2002 25,183 10,206 2,368 3,353 6,136 3,120 2003 24,284 5,885 1,197 4,261 6,969 5,972 2004 25,156 7,642 1,922 2,977 7,102 5,513 2005 25,000 8,391 2,749 B 3,771 5,652 4,437 2006 16,579 8,301 4 1,950 4,090 2,234 2007 17,857 5,001 1 2,170 4,112 6,573 2008 16,229 7,249 11 1,048 5,649 2,272 2009 16,628 4,067 4 1,494 5,953 5,110 Average % of total 35.7% 4.9% 12.3% 27.3% 19.8% A Snake River trap at Lewiston, ID, collects fish originating in Grande Ronde, Salmon, and Imnaha rivers; wild steelhead at this trap are not part of pre-assigned smolts in 2006 to 2009 – the few tags shown on wild steelhead were originally planned for use on wild Chinook tagging. B Includes 1,400 PIT-tagged wild steelhead released in Asotin Creek (Rkm 234). PIT-tagged Hatchery Steelhead Aggregate – Composition by Drainage Table A.9 Number of PIT-tagged hatchery steelhead smolts from tributaries above Lower Granite Dam (plus Snake River trap) used in the CSS analyses for migration years 1997 to 2007. Clearwater Snake Grande Salmon Imnaha River River trapB Ronde River River River Migr Total Year PIT tagsA (Rkm 224) (Rkm 225) (Rkm 271) (Rkm 303) (Rkm 308) 1997 35,705 12,872 725 6,039 9,394 6,379 1998 30,913 8,451 4,209 4,904 8,457 4,604 1999 36,968 11,486 3,925 5,316 9,132 6,808 2000 32,000 8,488 3,290 5,348 8,173 6,436 2001 29,099 9,155 3,126 4,677 7,859 3,995 2002 26,573 7,819 4,722 3,888 7,011 2,839 2003 26,379 4,912 4,171 3,113 7,764 6,123 2004 19,879 3,400 4,841 2,263 4,072 5,098 2005 23,520 7,228 3,354 2,395 3,684 6,802 2006 16,068 4,545 2,146 4,397 3,208 1,667 2007 26,608 3,893 2,545 8,979 8,820 2,086 Average % of total 27.1% 12.2% 16.9% 25.5% 17.4% A Total includes PIT-tagged hatchery steelhead released below HCD ranging between 57 and 301tags per year, and averaging 0.9% of total across the 11 years. B Snake River trap at Lewiston, ID, collects fish released in Grande Ronde, Salmon, and Imnaha rivers, and below Hells Canyon Dam. 178 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 PIT-tagged Hatchery Steelhead by Drainage and Run-type for 2008 Table A.10 Number of PIT-tagged hatchery steelhead smolts from tributaries above Lower Granite Dam used in the CSS analyses for migration year 2008. Median Length at PIT Tags Tributary / run Tag PIT Tag Hatchery Fish# / lb Tagging (mm) Released SiteA Proportion Release Clearwater – B CLWH 819,264 4.6 (none taken) 20,018 0.0244 DWOR 2,025,453 5.8 175 27,276 0.0135 IRRI 803,847 4.4 134 16,465 0.0205 LYFE 175,961 4.6 (none taken) 4,000 0.0227 Grande Ronde – A Imnaha – A IRRI 274,865 4.8 136 14,877 0.0541 Salmon – A MAVA 713,194 4.6 (none taken) 10,030 0.0141 A-run HAGE 1,208,489 4.1 (none taken) 18,116 0.0150 Salmon – B MAVA 907,723 4.7 (none taken) 24,442 0.0269 B-run HAGE 179,034 4.7 (none taken) 11,330 0.0633 A Hatchery at which steelhead were PIT-tagged: CLWH – Clearwater H; DWOR – Dworshak NFH; Irrigon H – IRRI; Magic Valley H – MAVA; and Hagerman NFH – HAGE. Niagara Springs H (NISP) is not included this year since its release of 1200 PIT-tagged smolts (none in monitor-mode) is not on scale with the magnitude of PIT-tagging at the other hatcheries being analyzed. B Tagged in fall 5-7 months before release; otherwise tagged in winter/spring 1-4 months before release. PIT-tagged Hatchery Steelhead by Drainage and Run-type for 2009 Table A.11 Number of PIT-tagged hatchery steelhead smolts from tributaries above Lower Granite Dam used in the CSS analyses for migration year 2009. Median Length at PIT Tags Tributary / run Tag PIT Tag Hatchery Fish# / lb Tagging (mm) Released SiteA Proportion Release Clearwater – B CLWH 748,928 4.7 (none taken) 21,193 0.0270 DWOR 1,297,545 6.5 185 28,307 0.0218 Grande Ronde – A IRRI 652,424 3.8 187 22,239 0.0341 LYFE 170,232 4.7 (none taken) 5,991 0.0352 Imnaha – A IRRI 187,401 4.5 179 20,848 0.1112 MAVA 812,563 4.8 (none taken) 15,486 0.0191 Salmon – A HAGE 1,249,216 4.4 (none taken) 16,576 0.0133 NISP 1,248,101 3.9 (none taken) 17,064 0.0137 Salmon – B MAVA 839,634 4.8 (none taken) 21,911 0.0261 HAGE 171,094 4.6 (none taken) 8,344 0.0488 Below HCD – A NISP 526,743 4.6 (none taken) 7,398 0.0140 A Hatchery at which steelhead were PIT-tagged: CLWH – Clearwater H; DWOR – Dworshak NFH; Irrigon H – IRRI; Magic Valley H – MAVA; Hagerman NFH – HAGE; and Niagara Springs H – NISP. B Tagged in fall 5-7 months before release; otherwise tagged in winter/spring 1-4 months before release. 179 1 2 Appendix B Dam-specific Transportation SARs Table B.1 Estimated dam-specific transportation SARs (%) of the PIT-tagged wild Chinook aggregate for juvenile migration years 1994 to 2008 (with 90% confidence intervals). Transported smolts from total PIT-tag release in years through 2005 and from Group TWS in years beginning 2006. Migr SAR(TLGR) Adult SAR(TLGS) A SAR(TLMN) A Adult Year % (CI%) # % (CI%) % (CI%) # Adult # 1994 0.67 (0.28 – 1.12) 7 0.52 (0.00 – 1.11) 2 NA None 1995 0.41 (0.18 – 0.68) 7 0.28 (0.00 – 0.84) 1 NA None 1996 0.37 (0.00 – 1.10) 1 1.18 (0.00 – 3.41) 1 NA None 1997 1.08 (0.00 – 2.37) 2 6.67 (0.00 – 14.8) 2 NA None 1998 1.34 (0.72 – 2.01) 11 0.84 (0.00 – 1.66) 3 1.27 (0.00 – 3.53) 1 1999 2.53 (1.82 – 3.28) 28 2.82 (1.49 – 4.47) 9 2.09 (0.72 – 3.58) 6 2000 1.22 (0.31 – 2.27) 4 2.46 (0.87 – 4.29) 6 1.07 (0.00 – 2.38) 2 2001 1.33 (0.46 – 2.23) 6 1.39 (0.00 – 4.11) 1 NA None 2002 0.61 (0.30 – 0.95) 10 1.08 (0.70 – 1.53) 20 0.60 (0.00 – 1.79) 1 2003 0.31 (0.19 – 0.45) 16 0.51 (0.28 – 0.75) 13 0.17 (0.00 – 0.50) 1 2004 0.55 (0.42 – 0.67) 49 0.46 (0.25 – 0.68) 13 0.72 (0.25 – 1.24) 6 2005 0.22 (0.16 – 0.29) 27 0.31 (0.16 – 0.48) 10 NA None 2006 0.72 (0.49 – 0.96) 28 0.72 (0.51 – 0.93) 31 1.24 (0.78 – 1.77) 17 2007 1.23 (x.xx – 0.xx) 26 1.44 (x.xx – x.xx) 9 0.89 (x.xx – x.xx) 3 2008 B 2.68 (x.xx – 0.xx) 94 1.63 (x.xx – x.xx) 28 0.92 (x.xx – x.xx) 4 A Transported smolt include first-time detected fish only from total release in years through 2005 and first-time and prior-detected fish from Group TWS in years beginning 2006. A Migration year 2008 is incomplete until 3-salt returns at GRA. 3 4 Table B.2 Estimated dam-specific transportation SAR percentages of PIT-tagged Rapid River hatchery spring Chinook for juvenile migration years 1997 to 2008 (with 90% confidence intervals). Transported smolts from total PIT-tag release in years through 2005 and from Group TWS in years beginning 2006. Migr SAR(TLGR) Adult SAR(TLGS) A SAR(TLMN) A Adult Year % (CI%) # % (CI%) % (CI%) # Adult # 1997 0.80 (0.58 – 1.02) 33 NA None 2.63 (0.00 – 7.89) 1 1998 2.12 (1.89 – 2.35) 239 1.18 (0.75 – 1.72) 16 1.02 (0.00 – 2.29) 2 1999 3.20 (2.89 – 3.52) 236 3.22 (2.79 – 3.64) 152 1.03 (0.31 – 2.13) 3 2000 2.34 (2.10 – 2.58) 243 1.89 (1.52 – 2.30) 79 2.23 (1.43 – 3.06) 27 2001 1.18 (1.04 – 1.33) 182 0.74 (0.49 – 1.00) 21 0.69 (0.17 – 1.29) 4 2002 1.14 (0.91 – 1.39) 61 0.94 (0.72 – 1.17) 50 1.05 (0.37 – 1.74) 6 2003 0.32 (0.23 – 0.43) 27 0.13 (0.05 – 0.23) 5 0.17 (0.00 – 0.53) 1 2004 0.39 (0.31 – 0.48) 53 0.30 (0.17 – 0.42) 16 0.18 (0.00 – 0.54) 1 2005 0.26 (0.19 – 0.33) 41 0.35 (0.22 – 0.51) 14 NA None 2006 0.67 (0.53 – 0.83) 53 0.54 (0.39 – 0.70) 34 0.63 (0.38 – 0.89) 17 2007 0.58 (0.42 – 0.75) 35 0.20 (0.00 – 0.41) 3 0.17 (0.00 – 0.42) 2 2008 B 1.49 (x.xx –x.xx) 161 1.33 (x.xx – x.xx) 69 0.98 (x.xx – x.xx) 7 A Transported smolt include first-time detected fish only from total release in years through 2005 and first-time and prior-detected fish from Group TWS in years beginning 2006. A Migration year 2008 is incomplete until 3-salt returns at GRA. 5 180 Table B.3 Estimated dam-specific transportation SAR percentages of PIT-tagged Dworshak hatchery spring Chinook for juvenile migration years 1997 to 2008 (with 90% confidence intervals). Transported smolts from total PIT-tag release in years through 2005 and from Group TWS in years beginning 2006. Migr SAR(TLGR) Adult SAR(TLGS) A SAR(TLMN) A Adult Year % (CI%) # % (CI%) Adult # % (CI%) # 1997 0.86 (0.54 – 1.23) 16 NA None NA None 1998 0.99 (0.85 – 1.14) 110 0.62 (0.41 – 0.85) 22 NA None 1999 1.26 (1.01 – 1.53) 62 1.29 (0.99 – 1.59) 49 0.83 (0.21 – 1.62) 4 2000 1.18 (1.01 – 1.37) 116 1.08 (0.83 – 1.32) 53 0.69 (0.40 – 1.03) 14 2001 0.36 (0.29 – 0.44) 60 0.44 (0.27 – 0.60) 18 0.16 (0.00 – 0.47) 1 2002 0.64 (0.44 – 0.83) 26 0.74 (0.54 – 0.96) 32 0.27 (0.00 – 0.60) 2 2003 0.28 (0.18 – 0.39) 20 0.28 (0.16 –0.41) 12 0.18 (0.00 – 0.38) 2 2004 0.17 (0.12 – 0.24) 22 0.45 (0.34 – 0.58) 37 0.36 (0.00 – 0.81) 2 2005 0.21 (0.16 – 0.29) 32 0.20 (0.11 – 0.31) 11 NA None 2006 0.39 (0.24 – 0.56) 16 0.41 (0.28 – 0.56) 25 0.52 (0.31 – 0.75) 15 2007 0.63 (0.32 – 0.99) 9 0.66 (0.21 – 1.33) 3 0.51 (0.00 – 1.20) 2 2008 B 0.48 (x.xx – x.xx) 17 0.93 (x.xx – x.xx) 35 1.84 (x.xx – x.xx) 13 A Transported smolt include first-time detected fish only from total release in years through 2005 and first-time and prior-detected fish from Group TWS in years beginning 2006. A Migration year 2008 is incomplete until 3-salt returns at GRA. 1 2 Table B.4 Estimated dam-specific transportation SAR percentages of PIT-tagged Catherine Creek hatchery spring Chinook for juvenile migration years 2001 to 2008 (with 90% confidence intervals). Transported smolts from total PIT-tag release in years through 2005 and from Group TWS in years beginning 2006. Migr SAR(TLGR) Adult SAR(TLGS) A SAR(TLMN) A Adult Year % (CI%) # % (CI%) Adult # % (CI%) # 2001 0.33 (0.18 – 0.50) 11 NA None NA None 2002 1.09 (0.66 – 1.53) 16 0.72 (0.29 – 1.18) 8 NA None 2003 0.32 (0.12 – 0.57) 5 0.57 (0.14 – 1.06) 4 NA None 2004 0.29 (0.10 – 0.48) 6 0.57 (0.14 – 1.04) 4 1.37 (0.00 – 4.17) 1 2005 0.32 (0.11 – 0.53) 6 0.95 (0.36 – 1.72) 5 NA None 2006 0.26 (0.08 – 0.53) 3 0.54 (0.19 – 0.95) 6 0.89 (0.22 – 1.69) 4 2007 0.51 (0.22 – 0.84) 7 0.20 (0.00 – 0.61) 1 1.08 (0.00 – 2.22) 3 2008 B 2.47 (x.xx – x.xx) 47 2.87 (x.xx – x.xx) 44 2.03 (x.xx – x.xx) 7 A Transported smolt include first-time detected fish only from total release in years through 2005 and first-time and prior-detected fish from Group TWS in years beginning 2006. A Migration year 2008 is incomplete until 3-salt returns at GRA. 181 1 Table B.5 Estimated dam-specific transportation SAR percentages of PIT-tagged McCall hatchery summer Chinook for juvenile migration years 1997 to 2008 (with 90% confidence intervals). Transported smolts from total PIT-tag release in years through 2005 and from Group TWS in years beginning 2006. Migr SAR(TLGR) Adult SAR(TLGS) A SAR(TLMN) A Adult Year % (CI%) # % (CI%) Adult # % (CI%) # 1997 1.49 (1.21 – 1.76) 87 2.86 (0.85 – 5.83) 3 3.23 (0.00 – 9.52) 1 1998 2.93 (2.65 – 3.22) 263 1.00 (0.46 – 1.62) 9 0.64 (0.00 – 1.88) 1 1999 4.36 (3.88 – 4.83) 206 3.23 (2.82 – 3.65) 161 4.93 (2.26 – 7.58) 10 2000 4.54 (4.18 –4.94) 386 3.26 (2.69 – 3.83) 92 2.45 (1.61 – 3.36) 19 2001 1.41 (1.23 – 1.58) 184 0.76 (0.49 – 1.05) 20 0.40 (0.00 – 0.91) 2 2002 1.63 (1.31 – 1.95) 70 1.43 (1.14 – 1.74) 59 1.00 (0.00 – 2.21) 2 2003 0.82 (0.66 – 0.98) 68 0.85 (0.62 – 1.10) 36 0.81 (0.34 – 1.31) 7 2004 0.43 (0.35 – 0.51) 70 0.36 (0.21 – 0.53) 14 NA None 2005 0.67 (0.59 – 0.77) 116 0.53 (0.36 – 0.72) 24 0.02 (0.00 – 0.07) 1 2006 1.35 (1.12 – 1.59) 80 0.98 (0.75 – 1.23) 46 1.60 (1.14 – 2.03) 37 2007 1.55 (1.21 – 1.90) 54 1.35 (0.77 – 2.05) 12 1.30 (0.65 – 1.98) 10 2008 B 1.24 (x.xx – x.xx) 69 1.24 (x.xx – x.xx) 49 1.91 (x.xx – x.xx) 15 A Transported smolt include first-time detected fish only from total release in years through 2005 and first-time and prior-detected fish from Group TWS in years beginning 2006. A Migration year 2008 is incomplete until 3-salt returns at GRA. 2 3 Table B.6 Estimated dam-specific transportation SAR percentages of PIT-tagged Imnaha hatchery summer Chinook for juvenile migration years 1997 to 2008 (with 90% confidence intervals). Transported smolts from total PIT-tag release in years through 2005 and from Group TWS in years beginning 2006. Migr SAR(TLGR) Adult SAR(TLGS) A SAR(TLMN) A Adult Year % (CI%) # % (CI%) Adult # % (CI%) # 1997 1.21 (0.84 – 1.66) 25 NA None NA None 1998 0.92 (0.69 – 1.18) 37 0.66 (0.17 – 1.22) 4 NA None 1999 3.43 (2.82 – 4.08) 74 2.31 (1.80 – 2.86) 53 2.63 (0.00 – 5.31) 3 2000 3.99 (3.50 – 4.48) 154 2.48 (1.91 – 3.09) 45 2.26 (1.18 – 3.36) 12 2001 0.73 (0.56 – 0.92) 42 0.37 (0.13 – 0.64) 6 NA None 2002 0.74 (0.38 – 1.12) 12 0.82 (0.51 – 1.19) 16 1.55 (0.00 – 2.97) 3 2003 0.58 (0.36 – 0.81) 18 0.64 (0.32 – 0.99) 10 0.67 (0.00 – 1.58) 2 2004 0.34 (0.21 – 0.48) 16 0.42 (0.20 – 0.68) 8 1.23 (0.00 – 2.91) 2 2005 0.34 (0.20 – 0.48) 15 0.15 (0.00 – 0.36) 2 NA None 2006 0.83 (0.47 – 1.22) 16 0.81 (0.54 – 1.11) 19 1.22 (0.61 – 1.90) 10 2007 1.26 (0.82 – 1.70) 21 0.39 (0.00 – 1.12) 1 NA None 2008 B 1.51 (x.xx – x.xx) 50 2.44 (x.xx – x.xx) 42 1.37 (x.xx – x.xx) 4 A Transported smolt include first-time detected fish only from total release in years through 2005 and first-time and prior-detected fish from Group TWS in years beginning 2006. B Migration year 2008 is incomplete until 3-salt returns at GRA. 182 1 Table B.7 Estimated dam-specific transportation SAR percentages of PIT-tagged wild steelhead in the annual aggregate groups for 1997 to 2007 (with 90% confidence intervals). Transported smolts from total PIT-tag release in years through 2005 and from Group TWS in years beginning 2006. Migr SAR(TLGR) Adult SAR(TLGS) A Adult SAR(TLMN) A Adults Year % CI % # % (CI%) # % (CI%) # 1997 1.87 (0.47 – 3.59) 4 NA None NA None 1998 0.34 (0.00 – 1.00) 1 NA None NA None 1999 2.69 (0.98 – 4.65) 6 4.44 (1.12 – 8.43) 4 2.99 (0.00 – 7.04) 2 2000 3.50 (1.51 – 5.64) 7 3.37 (0.00 – 6.86) 3 2.73 (0.74 – 5.36) 3 2001 3.09 (1.16 – 5.59) 5 NA None NA None 2002 3.91 (1.55 – 6.82) 5 1.61 (0.00 – 4.92) 1 2.22 (0.65 – 4.41) 3 2003 1.73 (1.15 – 2.40) 21 2.75 (1.71 – 3.85) 18 2.20 (0.84 – 4.07) 5 2004 0.91 (0.66 – 1.19) 31 0.87 (0.37 – 1.40) 7 0.63 (0.00 – 1.90) 1 2005 0.97 (0.71 – 1.25) 34 0.62 (0.27 – 1.01) 7 NA None 2006 1.23 (0.82 – 1.75) 19 1.56 (1.03 – 2.13) 22 1.16 (0.45 – 2.08) 5 2007 B 4.25 (3.40 – 5.10) 70 4.85 (3.61 – 6.28) 35 4.66 (2.69 – 6.94) 13 A Transported smolt include first-time detected fish only from total release in years through 2005 and first-time and prior-detected fish from Group TWS in years beginning 2006. B Migration year 2007 is incomplete until 3-salt returns (if any) occur at GRA after 7/1/2010. 2 3 Table B.8 Estimated dam-specific transportation SAR percentages of PIT-tagged hatchery steelhead in the annual aggregate groups for 1997 to 2007 (with 90% confidence intervals). Transported smolts from total PIT-tag release in years through 2007 since pre-assignment of hatchery steelhead smolts to Group TWS begins in 2008. Migr SAR(TLGR) Adult SAR(TLGS) A SAR(TLMN) A Adult Year % CI % # % (CI%) Adult # % (CI%) # 1997 0.59 (0.27 – 0.96) 9 NA None NA None 1998 0.63 (0.24 – 1.13) 5 0.28 (0.00 – 0.84) 1 0.64 (0.00 – 1.91) 1 1999 1.03 (0.50 – 1.69) 8 1.37 (0.34 – 2.57) 4 NA None 2000 3.01 (1.74 – 4.56) 14 1.37 (0.00 – 3.90) 1 1.09 (0.00 – 3.09) 1 2001 1.21 (0.30 – 2.32) 4 NA None NA None 2002 2.42 (0.70 – 4.93) 3 NA None NA None 2003 1.98 (1.49 – 2.49) 41 2.12 (1.51 – 2.76) 32 1.21 (0.59 – 1.86) 10 2004 1.70 (0.58 – 2.83) 6 4.60 (1.28 – 8.54) 4 NA None 2005 2.37 (1.43 – 3.43) 15 1.03 (0.00 – 2.29) 2 2.86 (0.00 – 8.82) 1 2006 1.65 (0.63 – 3.02) 5 2.58 (1.51 – 3.82) 13 2.37 (1.02 – 4.07) 7 2007 B 1.88 (1.22 – 2.59) 19 2.63 (1.78 – 3.51) 25 1.97 (1.13 – 3.02) 12 A Transported smolt include first-time detected fish only from total release in years through 2005 and first-time and prior-detected fish from total release in years beginning 2006. B Migration year 2007 is incomplete until 3-salt returns (if any) occur at GRA after 7/1/2010. 183 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Appendix C Estimate proportion of smolts experiencing TX, C0, and C1 passage routes The random pre-assignment of part of a release of PIT-tagged fish to monitormode (Group T) allows direct estimation of the proportion of smolts experiencing TX, C0, and C1 passage routes for the CSS PIT-tag groups in recent years. Pre-assigning of the CSS PIT-tag wild and hatchery Chinook and wild steelhead groups began with the 2006 smolt migration season. Pre-assignments do not begin until 2008 for PIT-tagged hatchery steelhead. Group T reflects the untagged fish passage experience under a given year’s fish passage management scenario. Methods In years prior to 2006, when marks were not pre-assigned to passage groups, the estimated number of smolts in each study category was adjusted to a projection of what that number could be if the proportion of smolts in each study category was the same as the run-at-large. This was done by utilizing the COE transportation and bypass numbers at LGR, LGS, and LMN, which are collected at the level of species and rearing type (the latter to a lesser degree of accuracy). These seasonal proportions were applied to the PIT-tagged smolts transported for a given group of interest at each dam and summed in LGR-equivalents to provide a projection of T0* smolts transported for that particular group. The projection of C1* bypassed was simply the remainder of (T0 + C0 –T0*) smolts. These projections are presented in Chapter 7 (Tables 7.7, 7.8, 7.13, and 7.14 for PIT-tagged wild Chinook, hatchery Chinook by individual hatchery, wild steelhead, and hatchery steelhead, respectively) of the CSS 2009 Annual Report (Tuomikoski 2009). In years 2006 and later, the proportion of TX, C0, and C1 smolts are computed directly from Group T for each corresponding CSS PIT-tag group. The reach survival rates Sj and collection probabilities Pj are computed with the total release (combined Group T smolts and the return-to-river Group R smolts) and passed to Group T, while the parameters R1, X12, X1A2, X1AA2, and C1 removals (d1, d2, d3, d4) and C0 removals (d0) are specific to Group T. As described in Chapter 4, equation 4.4 is used for estimating the TX smolt numbers, and the expectation equations 4.5 and 4.6, respectively, are used for estimating the C0 and C1 smolt numbers in Group T. In order for the proportion of Group T smolts being routed to TX, C0, and C1 to reflect those in-river migrants estimated alive to the tailrace of LMN expanded to LGR-equivalents, any removals below LMN need to be added back into the C0 and C1 estimates. The following equations are therefore used to estimate the number of PIT-tagged smolts in Group T for each of the three passage history experience categories: TX = X12 + X1A2 / S2 + X1AA2 / (S2•S3) [C.1] C0* = E(C0) + d0 = R1•S1•(1-P2)•(1-P3)•(1-P4) [C.2] C1* = E(C1) + d1 = R1•S1•[P2 + (1-P2)•P3 + (1-P2)•(1-P3)•P4] – [(d2 + d3/S2 + d4/(S2•S3)] [C.3] 184 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 and P[TX] = TX / (TX + C0* + C1*) [C.4] P[C0*] = C0* / (TX + C0* + C1*) [C.5] P[C1*] = C1* / (TX + C0* + C1*) [C.6] Results Beginning in 2006 there was a major shift in the transportation operations within the FCRPS. The start of transportation was delayed at the three Snake River collector dams due to research findings suggesting that fish transported too early in the migration season survival less than if the fish were allowed to migrate in-river. In years prior to 2006, transportation commenced as soon as the Snake River collection facilities became operational each year, which was around March 25 at LGR and April 1 at LGS and LMN. For years 2006 to 2009, the start of collecting fish for transportation has been delayed to: Year Lower Granite Dam (LGR) Little Goose Dam (LGS) Lower Monumental Dam (LMN) 2006 2007 2008 2009 April 20 May 1 May 1 May 1 April 24 May 8 May 9 May 5 April 28 May 11 May 12 May 8 In years prior to 2006, the start time of transportation encompassed most of the emigrating groups of CSS marked fish. With the change to a later start of transportation beginning in 2006, there is now a portion of the population that migrates entirely in-river through the hydrosystem before transportation begins. This reduces the proportion of the smolt population being transported in a given year as seen in Table C.1 particularly in 2007 through 2009 with the later start of transportation compared to 2006. The outmigration of PIT-tagged Dworshak NFH spring Chinook tends to commence earlier than the other four CSS PIT-tag hatchery Chinook group and has consistently had the lowest proportion transported in all four years (range 8.3% - 52.2%). The other four CSS hatchery groups had fairly similar proportions transported within any given year, with the highest proportions occurring in 2006 (range 65.3 – 70.5%) and lowest proportions in 2007 (range 22.5 – 47.3%). The PIT-tagged wild Chinook aggregate also had the highest proportion transported in 2006 (66.4%) and lowest in 2007 (21.3%). The PIT-tagged wild steelhead aggregate likewise had the highest proportion transported in 2006 (64.9%), while both years 2007 and 2008 had the lowest proportion transport at 40.1% and 40.5%, respectively. With the later start of transportation in 2007 to 2009 (the first half of May), the goal of reaching a 50% spread-the-risk transport versus in-river migration appears to be more attainable now than was possible in earlier years for both wild Chinook and wild steelhead stocks. 185 1 2 3 4 Table C.1 Estimated proportion of PIT-tagged smolts in CSS wild and hatchery Chinook and wild steelhead groups experiencing passage through transportation, bypass, or without detection at the Snake River transportation sites (based on PIT-tagged fish in the monitor-mode (TWS) group). (Non-parametric 90% confidence intervals are shown.) Fish source1 Transportation LL Passage w/o detection Bypass passage Pr(C0) LL UL Pr(C1) LL UL Smolt Migration Year 2006 RAPH 0.705 0.697 0.713 0.213 0.209 0.218 0.082 0.074 0.090 DWOR 0.522 0.515 0.530 0.319 0.314 0.325 0.158 0.151 0.166 CATH 0.680 0.654 0.706 0.256 0.241 0.269 0.064 0.040 0.090 MCCA 0.653 0.643 0.663 0.275 0.269 0.281 0.072 0.062 0.081 IMNA 0.669 0.654 0.685 0.215 0.206 0.223 0.116 0.101 0.131 WCh 0.664 0.652 0.676 0.151 0.147 0.156 0.184 0.173 0.197 WSt 0.649 0.631 0.667 0.072 0.067 0.077 0.280 0.262 0.298 Smolt Migration Year 2007 RAPH 0.347 0.341 0.354 0.519 0.513 0.525 0.134 0.126 0.141 DWOR 0.083 0.081 0.086 0.687 0.682 0.692 0.230 0.225 0.235 CATH 0.473 0.452 0.494 0.465 0.451 0.479 0.062 0.042 0.081 MCCA 0.274 0.267 0.281 0.616 0.610 0.623 0.110 0.102 0.117 IMNA 0.225 0.216 0.234 0.552 0.543 0.561 0.223 0.212 0.234 WCh 0.213 0.207 0.220 0.490 0.483 0.496 0.297 0.289 0.306 WSt 0.401 0.385 0.416 0.385 0.373 0.399 0.214 0.198 0.229 Smolt Migration Year 2008 RAPH 0.585 0.578 0.593 0.281 0.275 0.286 0.134 0.127 0.141 DWOR 0.338 0.331 0.345 0.470 0.463 0.478 0.192 0.184 0.199 CATH 0.600 0.579 0.619 0.293 0.281 0.306 0.107 0.088 0.125 MCCA 0.521 0.511 0.531 0.361 0.353 0.368 0.118 0.109 0.127 IMNA 0.541 0.528 0.552 0.283 0.275 0.292 0.176 0.164 0.188 WCh 0.428 0.417 0.437 0.299 0.293 0.306 0.273 0.263 0.284 WSt 0.405 0.390 0.420 0.317 0.305 0.329 0.278 0.261 0.293 Smolt Migration Year 2009 RAPH 0.437 0.430 0.443 0.404 0.398 0.410 0.159 0.152 0.167 DWOR 0.341 0.334 0.347 0.478 0.472 0.485 0.181 0.173 0.189 CATH 0.562 0.543 0.582 0.353 0.341 0.366 0.085 0.066 0.103 MCCA 0.404 0.395 0.412 0.468 0.460 0.475 0.128 0.120 0.137 IMNA 0.504 0.491 0.517 0.373 0.364 0.383 0.123 0.110 0.135 WCh 0.426 0.417 0.435 0.225 0.221 0.230 0.349 0.339 0.359 WSt 0.453 0.439 0.467 0.190 0.183 0.198 0.357 0.343 0.372 1 Hatchery Chinoook: DWOR =Dworshak H; IMNA=Imnaha AP; MCCA=McCall H; RAPH=Rapid River H; and CATH=Catherine Creek AP. Wild Chinook aggregate is WCh and wild steelhead aggregate is WSt. 5 6 7 8 9 10 11 12 13 14 15 16 Pr(TX) UL There are several benefits of having Group T for estimating these three passage experience proportions. The previous constraint of limiting transportation to first-time detects has been eliminated in creating the TX group, and so fish bypassed at an upstream dam are now included if transported at a downstream dam. Delaying the start of transportation does not add any complication to the estimation process. Since Group T follows the monitor-mode operations at the transportation sites, it best reflects the untagged population of transported and bypassed smolts at those sites. Therefore, there is no need to adjust the PIT-tag data using proportions of collected run-at-large smolts transported and bypassed at the dams, which is available only at the species and rearing type level, to individual PIT-tagged hatchery groups that may have different passage timing history. 186