Arctic WOLVES - NWT International Polar Year

Transcription

Arctic WOLVES - NWT International Polar Year
IPY PROJECT:
Arctic WOLVES
(Arctic Wildlife Observatories Linking
Vulnerable EcoSystems)
Donald Reid
Wildlife Conservation Society Canada, Whitehorse
What is Arctic WOLVES ?
• International investigation of arctic tundra ecosystems.
• Network of wildlife observing stations in Canada, Norway, Russia,
Netherlands & Greenland (Denmark).
• Repeated measurements of selected parts of the tundra
ecosystem for comparisons around the globe and through time.
Where in Canada ?
Alert
Eureka
Herschel Island
Bylot Island
Walker Bay
Cape Churchill
Akimiski Island
Where in Yukon ?
North Slope – Inuvialuit Settlement Region
2007 through 2010
Herschel Island
ALASKA
YUKON
Komakuk Beach
Yukon Research Goals
 To better understand how energy flows
through the tundra food web.
 Do predators eat so many herbivores that plants do
well, or do herbivores eat most of the plant growth ?
 To investigate possible effects of
climate change on distribution, abundance
and timing of species in the food web.
 What changes have taken place in recent decades ?
Climate Change ?
( Bob Sagar, Don Reid)
ARCTIC TRENDS
•
•
•
•
Warmer Temperatures
Longer Ice-Free Season
Earlier Snow Melt
Later Freeze-up
YUKON NORTH SLOPE
EVIDENCE
• Permafrost Melt and Slumping
• Increasing Coastal Erosion
Frank Doyle
Frank Doyle
TEMPERATURE TRENDS ( 0.5 Co / decade )
Komakuk
mean annual temperature (C)
-5
Komakuk Annual
Shingle Point
-10
y = 0.0509x - 12.401
-15
mean annual temperature (C)
-5.0
Shingle Pt Annual
-10.0
y = 0.0453x - 11.01
-15.0
-20.0
-25.0
1978
1988
date
1998
mean monthly air temperature
(C)
-10.0
February
-15.0
-20.0
-25.0
-30.0
-35.0
1958
1968
1978 date 1988
1998
2008
-15.0
-5.0
1958
2008
1968
1978
1988
date
1998
10.0
June
5.0
0.0
1958
1978
date
1998
-20.0
mean monthly air temperature
(C)
15.0
March
1958
1968
1978
1988
date
1998
mean monthly air temperature
(C)
-5.0
2008
-10.0
1958
1978
date
1998
-20.0
-25.0
1958
1978
date
1998
1998
2008
0.0
October
-5.0
-10.0
-15.0
-20.0
1958
1978
date
1998
November
-30.0
-15.0
August
1958
1968
1978
1988
date
1998
2008
December
-20.0
10.0
-15.0
1988
date
-25.0
15.0
April
1978
-20.0
0.0
-35.0
1968
-15.0
5.0
-30.0
1958
-10.0
July
10.0
-25.0
2008
mean monthly air temperature (C)
1968
mean monthly air temperature (C)
1958
September
0.0
-10.0
-35.0
mean monthly air temperature
(C)
0.0
-5.0
-30.0
mean monthly air temperature
(C)
5.0
May
mean monthly air temperature
(C)
-15.0
5.0
mean monthly air temperature
(C)
January
mean monthly air temperature
(C)
mean monthly air temperature
(C)
mean monthly air temperature
(C)
KOMAKUK
-10.0
-25.0
5.0
-30.0
0.0
-35.0
1958
1978
date
1998
1958
1968
1978
1988
date
1998
2008
Changes in the Food Web ?
Herschel Island Food Web
SNOWY OWL
PEREGRINE
FALCON
WOLVERINE
RED AND
ARCTIC FOXES
WEASELS
SHORTEARED
OWL
LONGTAILED
JAEGER
PARASITIC
JAEGER
GRIZZLY
BEAR
ROUGHLEGGED
HAWK
RAVEN AND
GULLS
CARRION
CARIBOU
MUSKOX
EIDERS
SEABIRDS
LEMMINGS
GEESE
PTARMIGAN
PASSERINE
AND SHORE
BIRDS
INSECTS
HERBS
GRASSES
AND
SEDGES
A. Kenney
DRYAS
SAXIFRAGA
WILLOWS
F. Mueller
MOSSES
A. Blachford
Vegetation
( Scott Gilbert, Isla Myers-Smith, Dorothy Cooley, Catherine Kennedy, Jill Johnstone )
TRENDS ALREADY REPORTED
• Arctic is Greening ( More plant
growth each summer)
• Shrubs do particularly well.
• Lichens lose out
IPY WOLVES RESULTS - YUKON
• Moderate annual growth (120-270
g / m2 dry matter, vascular)
• Shrubs expanding
• Lichens declined since 1980s
• Change in vigour (structure) of
existing species, rather than species
turnover
Insects
( Maria Leung, Scott Gilbert, Don Reid )
ABUNDANCE (Biomass )
• Six times higher on Herschel I.
than Bylot I. ( high arctic ).
• Historical trends ?
RANGE CHANGES ?
Maria Leung
• 6 butterfly species on Herschel
(2007-09) not previously
reported.
• 2 new crane fly species.
• Northwards range expansion ?
Fritz Mueller
Lemmings & Voles
( Charles Krebs, Alice Kenney, Scott Gilbert, Don Reid, Maria Leung, Liz Hofer)
SPECIES
•Normal tundra species:
Collared Lemming, Brown
Lemming, Tundra Vole.
• Komakuk: Northern Redbacked Vole & Singing Vole –
expansion north from
mountains ?
Alice Kenney
• Tundra & Barren-ground
Shrews fully documented.
Fritz Mueller
Fritz Mueller
Cameron
Eckert
ABUNDANCE
• Limited historical data
• Herschel – strong
population fluctuations
(2 – 50 / ha ).
• Komakuk - steady low
densities (<3 / ha ).
• Same general patterns
as in recent decades.
• Noteworthy lack of
typical lemming cycles on
mainland.
Fritz Mueller
LEMMING WINTER HABITAT
• Experiment to increase snow
depth with snow fences.
• Quality of tundra as winter
habitat increases with snow depth,
and with earlier autumn snow.
Alice Kenney
Alice Kenney
Frank Doyle
Birds
( Frank Doyle, Dave Mossop, Mike Nelligan, Alice Kenney, Darielle Talarico, Alistair Blachford,
Maria Leung, Scott Gilbert, Don Reid)
NESTING SPECIES
• Comparing IPY to mid-1980s.
• Declines: Ruddy Turnstone,
Red-necked Phalarope, Baird’s
Sandpiper.
• New nesters: Least Sandpiper,
Buff-breasted Sandpiper, Sandhill
Crane, Peregrine Falcon.
• Possible links to climate: Rising
sea levels / flooding of beaches &
lagoons; increased vegetation
cover; more insect / arthropod
biomass.
• Independent of climate:
Peregrine Falcon
Photos:
Frank Doyle
TIMING OF NESTING
• Comparing IPY to mid-1980s
• Laying dates vary between
years, related to spring
temperatures and snow melt.
• Median hatch date now
earlier for all species, by 3 10 days.
• Climate related because of
link of timing to snow melt.
• Concern of mismatch of
hatching with maximum insect
abundance. Not an obvious
problem in Yukon.
Photos: Frank
Doyle
Savannah Sparrow
Lapland Longspur
Baird's Sandpiper
Semipalmated
Sandpiper
2008
Rough-legged Hawk
2007
Peregrine Falcon
1986
Common Eider
Greater White-fronted
Goose
American Golden
Plover
Long-tailed Jaeger
Common Redpoll
Horned Lark
American Pipit
DAY
10
Month
12
14
16
18
20
22
24
26
28
30
2
4
June
Range of Hatch Dates in 1986 compared to 2007 and 2008
6
8
10
12
14
16
18
20
22
24
July
( No PEFA nesting records in 1986.)
RAPTORS
Snowy Owl
 Herschel I. key nesting site
 Likely negative effects of
increased vegetation
Short-eared Owl
 Competitor with Snowy Owl
& other raptors.
 May benefit from increased
vegetation.
Peregrine Falcon & Roughlegged Hawk
 Cliff nesters
 Up to 50% nests lost
during IPY when permafrost
“cliffs” collapse.
 Climate related, but
localized, impact.
Caribou & Muskoxen
( Don Reid, Dorothy Cooley, Lee-John Meyook, Richard Gordon )
CARIBOU
• Porcupine herd and Herschel Island.
• Early 1970s none resident, and rare
visitors. Humans resident on island.
• 1980s to present: Common in summer.
 2008 summer: 237 with 41 calves
(2.2 caribou / km2 ).
• Winter residents in recent decade
( hunted in Dec, Mar and April ). WHY ?
 Winter food – lichens
 Immediate access to spring forage
• Sustainability of wintering herd ?
 Lichen decline since 1980s
 Thaw-freeze snow crusting (forced
caribou off island in 2008-09).
Fritz Mueller
MUSKOXEN
• Herschel Island
• Early 1970s – none; occasional on
mainland
• Since late 1980s: Regular in summer;
some wintering now.
• 2008: 43 including 11 calves ( 0.4 / km2 )
• Wintering animals stayed on Island
through 2008-09 thaw-freeze event.
• Changes not related to warming climate
Frank Doyle
Alice Kenney
Foxes
( Daniel Gallant, Brian Slough, Don Reid )
ARCTIC & RED FOX
• North Yukon area of overlap.
• Red fox can out-compete and kill
arctic fox.
Steve Zack
• Has a warming climate provided an
advantage to red fox.
• Den occupancy surveys in 1970s,
1985-89, and 2008-09 (IPY) show
stable situation.
 No change in abundance of
one species compared to another
 Dens have changed equally
between species.
Daniel Gallant
Daniel Gallant
• Warming climate not enough to give
red fox an advantage.
• Food abundance is strongly
limiting both species.
Maria Leung
SUMMARY of CHANGES
Related to Changing Climate:
 Permafrost Melt & Coastal Erosion – habitat loss
 Storm surges & higher sea level – habitat loss
 Vegetation – Increased growth, competition
changes, changing habitat structure.
 Distribution of mobile species – new arrivals,
competition changes
 Timing of events – earlier nesting
Not Directly Related to Changing Climate:
 Changes in Caribou and Muskoxen abundance
 Changes in some other species – Peregrine Falcon
Noteworthy Lack of Change:
 Most Species – vegetation, birds, mammals
 Fox species – den occupancy and abundance
Principal Researchers on Yukon Project
 University of British Columbia - Charles Krebs, Alice Kenney, Alistair






Blachford
University of Quebec at Rimouski – Daniel Gallant, Dominique Berteaux,
Elise Bolduc, Laura McKinnon, Joel Bety
Lakehead University - Doug Morris, Som Ale, Bill Halliday
Yukon College – Scott Gilbert, Dave Mossop
University of Alberta – Isla Myers-Smith
Wildlife Conservation Society Canada – Don Reid
Private Researchers – Frank Doyle, Maria Leung, Liz Hofer, Michael
Nelligan, Polly Madsen, Olivier Cimon
Principal Collaborators
 Qikiqtaruk Territorial Park (Yukon Parks) – Richard Gordon, Lee-John
Meyook, Edward McLeod, Colin Gordon, Deon Arey, Dave Ladret, Cameron
Eckert
 Aklavik Hunters and Trappers Committee – Agnes Tardiff, Edward McLeod,
Sam McLeod, Billy Archie
 Parks Canada – Ian McDonald, Seth Oldham, J-F. Bisaillon, Linh Nguyen
 Yukon Environment - Dorothy Cooley, Tom Jung
 Canadian Wildlife Service – Wendy Nixon
Logistics
 Polar Continental Shelf Program; Aklak Air; Canadian Helicopters; Great
Slave Helicopters; Northwright Aviation; Aurora Research Institute