Tanzania Forest Conservation Science Report 154

Transcription

Thomas Bruce(RO), Corinne Bailey(ARO)
TZF 154 end of phase report
TANZANIA FOREST RESEARCH
PROGRAMME
Utende Village, Mafia Island, Tanzania
TZF Phase 154 Science Report
October 14th- December 15th
Thomas Bruce (Research Officer)
Corinne Bailey (Assistant Research Officer)
1
Staff Members
Name
Thomas Bruce
Corinne Bailey
Position
Research Officer (RO)
Assistant Research Officer (ARO)
2
1.0 Introduction…………………………………………………………………...…………...4
1.1 Area overview…………………………………………………………………………...4-6
2.0 Training………………………………………………………………………….………...6
2.1 Briefing sessions…..……………………………………………………………….……...6
2.2 Science lectures………………………………………………………………….…….......6
2.3 Field training…………………………………………………………………….…….......7
3.0 Research work programme…………………………………………………………..........8
3.1 Overview……………………….……………………………..……………………….......8
3.2 Survey sites…………………………………………………………………………….8-10
3.3.0 An Investigation into the effects of anthropogenic disturbance on habitat structure and
bird community biodiversity on Mafia Island Tanzania.…..……………………………..11-23
3.3.1 Abstract………………………………………………………………………...11
3.3.2 Introduction…………………………………………………………..……..11-13
3.3.3 Methods……………………………………………………………………..13-15
3.3.4 Results………………………………………………………………………15-21
3.3.5 Discussion……………………………………………………….……….....21-23
3.4.0 A socio-economic survey of hippo-human conflict in Ndagoni, Tanzania………...24-28
3.4.1 Abstract………………………………………………………………………...24
3.4.2 Introduction…………………………………………………….…..…..…...24-25
3.4.3 Methods………………………………………………………………...………25
3.4.4 Results…………………………………………………………..………......25-26
3.4.5 Discussion………………………………………………………………... ..26-28
4.0 Proposed scientific programme for next phase……………………………………….29-30
4.1 Proposed research for next work phase…………………………………………..……...29
4.2 Potential Contributions of future work……………………………………………….29-30
5.0 References………………………………………………………………….…….…...30-34
6.0 Appendices………………………………………………………………….…….……...35
6.1 Annex I………………………………………………………………………..35-37
6.2 Annex II………………………………………………………………………37-44
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1.0 Introduction
Mafia Island and the small group of surrounding islets are part of the Zanzibar Archipelago
off the eastern coast of Tanzania. The island lies approximately 20 km across from the Rufiji
River, on the far edge of the Rufiji Delta. Like the Rufiji River, the island itself is surrounded
by mangroves throughout most of its margin, with coastal forests and grasslands occurring
more inland, on parts of the island untouched by agriculture. While the coastal forests of
Mafia Island are secondary forest, the mangrove forest appears to have been harvested
relatively sustainably in the past, allowing primary mangrove forest to persist (Taylor et al.,
2003). However, as Greenway (1988) discovered the majority of the island’s primary forest
has been cleared for agricultural use, this has formed coastal thicket and small patches of
fragmented forest. One of the main forms of agriculture present are coconut plantations,
which are abundant across the Island.
Established in 1991, the Mafia Island Marine Park covers a large portion of the ocean
surrounding the eastern and southern edge of the island, along with some of the
neighboring islets, such as Chole and Juani (Fig. 1). The Mafia Island Marine Park extends
onto the land, encompassing some of the mangrove forest along the eastern edge of the
island, in addition to the marine habitats throughout Chole Bay.
Islands such as Mafia are important for global biodiversity as they often contain endemic
species. Mafia is part of the Rufiji-Mafia-Kilwa Marine RAMSAR site, which classifies these
wetlands as important for international conservation, used by birds for roosting and
overwintering sites (RAMSAR, 2012). Anthropogenic pressure is increasing on the wetlands
within the area, as rice paddy farming has begun to expand along with around 50
rudimentary snare traps being placed for wading birds covering approximately 200 meters
in the wetlands(T.Bruce pers obvs.). For this reason TZF programme has focused on the
impacts of anthropogenic disturbance on vegetation structure within habitats and the effect
this has on bird community biodiversity.
1.1. Area overview
The Frontier Tanzania Forest Research Programme (TZF) is located on Mafia Island, off the
coast of mainland Tanzania, East Africa. Mafia Island is part of the Tanzanian Spice Islands,
together with Unguja and Pemba. It is centrally located in a group of 15 small sandstone and
coral rag islands in the Indian Ocean, with a total land area of 394 km2 (Figure 1). Mafia is
the largest of these, measuring approximately 50km in length by 15km across at its widest
point.
Much of Mafia’s coastline and surrounding sea areas are part of the Mafia Island Marine
Park (MIMP), which extends predominantly across the south eastern corner of the island
and covers an area of 822 km2 (Goossens et al., 2006). The marine park envelopes some of
the 15 islands in the archipelago, several of which are inhabited, with a total estimated
population of 41,000 as of 2002 (Caplan, 2011). Individuals living on this archipelago are
mostly smallholder farmers that are involved in mixed farming and fishing. The main
agricultural practices include plantations of coco- nuts, cassava, rice, pigeon pea,
pineapples, cashew and mango trees (Goossens et al., 2006).
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As one of the six districts of the Pwani Region, Mafia Island is governed from the mainland.
As with other coastal forests in Tanzania, Mafia Island’s forests and rich biodiversity are
threatened by increased pressure on these resources, lack of government resource
management, increased poverty and limitations on financial and human resources for
conservation (Chami, 1999). The whole of the island became part of The Rufiji Delta- KilwaMafia-RAMSAR site in 2004, which gives a framework for the “wise use” of resources in
areas of natural importance. This framework increased management of the environment,
giving different levels of protection to areas that were of scientific or conservation
importance, as well as considering its uses for local people (Durand, 2004). Despite this,
local opinion is that there is little evidence of responsible bodies taking this framework into
consideration (Rubens and Kazimoto, 2003). More patrolling is required and alternative
sources should be introduced to help to relieve these areas, such as forest plantations to
help take the pressure of mangrove stands and educate locals on the importance of the
forests (Interact, 2010). Habitat destruction is one of the main drivers of species extinction
worldwide and studies have recognised the need for greater effort in protecting threatened
biodiversity in tropical hotspots (Mittermeier et al., 2008). This is especially important when
coastal Tanzanian forests have an estimated 75 endemic plant species and 61 endemic
vertebrate species per 100 km2 of forest area (Myers et al., 2000).
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Figure 1: A satellite map of Mafia island with Utende village, the location of camp is marked
by the red point with a black spot.
2.0 Training
2.1 Briefing sessions
After deployment, volunteers are given briefing sessions on health and safety, medical
issues, TZF project history and camp life as listed in (Table 1).
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Table 1: Briefing sessions conducted during phase 154.
Briefing session
Presenter
Health & Safety
RG
Medical brief
RG
Introduction to TZF project
TB
Camp life and duties
TB,CB
Hazardous flora and fauna on mafia
RG
2.2 Science lectures
Introductory science lectures are given on the TZF research programme and survey
methodology as listed in (Table 2). Revision of marine and avifauna to practice species
identification are undertaken in conjunction with the current projects taking place within
the Terrestrial programme. Lectures and presentations on specific aspects of the TZF
research programme are shown to both staff and volunteers and both are encouraged to
create their own presentations to further their understanding and knowledge. New staff
and volunteers are required to pass a bird identification test with 95% success before they
can carry out surveys independently.
Table 2: Science lectures given in 154.
Science Lectures
Presenter
Introduction to Tanzania Forest Programme
TB
Survey Techniques and Methods
TB,CB
Sengi Conservation and Surveying
TB
Whale Shark Conservation and Biology
TB,CB
Introduction to Birds of Mafia
TB,CB
Bird Identification techniques
TB,CB
2.3 Field training
Subsequently after relevant lectures and background material on each project has been
shown, volunteers are trained on how to use all equipment and are then taken out into the
field to conduct practice surveys (where data is not officially recorded) under the
supervision of staff members.
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Table 3: Training sessions given to new volunteers.
Training sessions
Presenter
Bird identification in field and at camp
TB,CB
Habitat Surveying techniques in the field
TB,CB
Training in field applications of GPS, and compass use
TB,CB
Training in the use of specialist field equipment
TB,CB
Training in survey techniques, quadrats, line transect, point counts
TB,CB
3.0 Research Work Programme
3.1 Overview
The Tanzanian Forest Research Programme has developed on-going projects and begun
trialing new ones.
 In phase 154 a study was conducted investigating how bird community biodiversity
was affected by human disturbance and vegetation structure. A new transect was
added to the paddy fields habitat, this gave us a total of 10 transects two in each
habitat. Survey methodology was changed from point counts to line transects to
reduce the risk of double counting.
 A socio-economic questionnaire was carried out examining the attitudes of locals
towards hippos and wildlife conflict, and to establish how this affects their
livelihoods.
 A trial survey was begun investigating Sengi abundance using sign surveys of nests,
and measuring habitat variables to establish abundance and habitat preference
around Utende.
 A database of Whale shark images has been compiled to try and identify individuals
and see how the population demography off the coast of Killondoni changes through
time.
3.2 Survey Sites
During phase 154, all bird survey sites were located surrounding Utende village (Figure 1).
Many non-native plant species such as cashew nut and coconut trees are present amongst
scrubland as well as paddy fields and grassland for rice cultivation and cattle grazing, with
small areas of wetland and heavily fragmented forests. There are currently a total of ten
bird survey transects in five different habitats; two wetland transects, two paddy field
transects, two scrubland transects used for cattle grazing, two coastal transects and two
forest habitats. Figure 1 shows the locations of the transects in relation to one another and
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major features such as the main road. Table 1 summarises the habitats and their GPS coordinates for the start points of the bird line transect.
Table 1: Summary of line transect names and GPS locations for the bird biodiversity, habitat
structure and disturbance surveys.
Site name/Number
Wetlands 1
Wetlands 2
Paddy fields 1
Paddy Fields 2
Cattle grazing site 1
Cattle grazing site 2
Coastal site 1
Coastal site 2
Forest 1
Forest 2
GPS Coordinates
S 07'58.002 E 039'44.485
S 07'58.093 E 039'44.726
S 07'58.102 E 039'44.456
S 07’58.003 E039’44.179
S 07'58.156 E 039'44.477
S 07'58.153 E 039'44.497
S 07’58.031 E 039’44.556
S 07’58.295 E 039’44.549
S 07’58.378 E 039’44.130
S 07’58.387 E 039’4.077
Paddy Fields 2
1
Figure 1: A satellite Map of the bird survey transect locations
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The hippo socio-economic survey took place in Ndagoni village north of Utende (Figure 2),
this is a land locked area with significant wetland habitats suitable for supporting the small
hippo population. The interview was conducted on the farm of a local man who was widely
respected and knowledgeable about the hippo population, he was able to gather several
farmers to take part in the survey.
Figure 2: A satellite map of Mafia island with the location of Ndagoni village highlighted by
the solid red dot, in relation to Utende the red point with a black centre.
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3.3.0 An Investigation into the effects of anthropogenic disturbance on habitat structure
and bird community biodiversity on Mafia Island Tanzania.
3.3.1 Abstract
As part of the Rufiji-Mafia-Kilwa Marine Reserve, Mafia island was designated a RAMSAR
site in 2004. Mafia Island previously had extensive coastal forests, which have been cleared
for coconut tree plantations, cattle grazing, the planting of other crops and the removal of
wood to build structures and produce charcoal. This study aimed to quantify the effects of
human disturbance on physical habitat structure, bird biodiversity and species richness,
across a range of habitats including wetlands, forest, cattle grazed and coastal, using
standardised line transects and repeated surveys to compare the habitats and disturbance
levels. Species observed are likely an underestimate based on species accumulation curves.
All of the habitats were found to have very high species diversity, particularly coastal and
wetlands. Bird biodiversity was significantly positively correlated with disturbance
(p=<0.05). Despite being heavily disturbed, the wetlands supported the most species of any
of the habitats and had the highest species diversity measures. This provides support for the
requirement of wetland habitat to be protected, owing to its significant role for global bird
biodiversity.
3.3.2 Introduction
Areas are often prioritized within conservation for protection and management, this is due
to the limited resources available to conservationists on local and global scales (Brooks et al.
2006.) These areas can be selected and prioritised accordingly based on a range of criteria
including the severity of threat or changes to biodiversity (Myers et al. 2000), the
conservation of endemic birds (Scharlemann et al. 2004) or the presence of flagship species
(Williams et al. 2000). However, for prioritisation strategies to be effective the information
they are based on needs to remain contemporary to ensure that conservation objectives
remain relevant (Doggart et al. 2006). Therefore, monitoring is a vital tool in the process of
conservation and management of protected areas.
Tanzania, and specifically the coastal forests of Mafia Island are part of the coastal forests of
Eastern Africa’s biodiversity hotspot (Mittermier, 2005). There are a number of criteria that
an area has to meet to qualify as biodiversity hotspot. They have to be areas of high species
endemism and biodiversity that have undergone significant habitat loss of up to 70% of
their primary vegetation (Myers et al. 2000).
Mafia Island previously had extensive coastal forests, which since the 1930’s have been
cleared for coconut tree plantations, cattle grazing, the planting of other crops, such as rice,
and the removal of wood to build structures and produce charcoal. This has resulted in
small patches of forest and coastal thicket remaining on the east of the island (Greenway,
1988). Due to these anthropogenic pressures the Mafia Island Marine Park was established
in 1995, with the aim of monitoring and protecting biodiversity and ensuring the sustainable
farming practices and the use of mangroves on the island. The boundaries of the marine
park extend over the southern and eastern edge of the island covering an area of around
822km2 (Goosens et al. 2006). It is vital that frequent monitoring occurs so that the strategic
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adaptive management plan (SAMP) employed by the marine park can be updated to protect
biodiversity and ecosystem health.
Global bird biodiversity has been declining rapidly due to a range of anthropogenic impacts,
such as habitat loss, hunting and the introduction of disease and invasive species (Bird Life
international 2014a). The IUCN Redlist has classed 197 species as ‘critically endangered’
(Bird Life international 2014b). Estimates for the rate of extinction of birds globally predict
that by 2100, 6-14% of all bird species will become extinct and that 28-56% on islands will
be functionally extinct no longer providing ecosystem services or containing viable
populations (Şekercioğlu et al. 2004). Islands contain significantly more endemic species due
to their geographical isolation, the loss of an endemic species on an island is equivalent to a
global extinction as recolonization cannot occur (Begon, Townsend and Harper, 2006).
Despite one fifth of the worlds bird species being confined to islands, over 90% of bird
species extinctions have occurred on islands (Johnson 1990). Therefore, monitoring of bird
populations is important for global biodiversity due to their high endemism on islands.
Birds are often regarded as indicators of ecosystem health, and a decline in their
biodiversity can provide an early warning to the decline of the biodiversity of other species
such as mammals (Brooks et al. 2000). For example, in a study by Burgess et al. (2000) it was
demonstrated that areas that were suitable for bird species richness captured 77% of
mammals species present in the same area. This demonstrates the potential of birds to act
as indicators for biodiversity decline across other taxa.
As part of the Rufiji-Mafia-Kilwa Marine Reserve, Mafia island, was designated a RAMSAR
site in 2004. This classification means it is regarded as an important wetland habitat
(RAMSAR, 2012) and is an important wintering ground for migratory birds (Mwalyosi 2002).
There is significant pressure on the wetlands from anthropogenic degradation of habitat,
primarily from the expansion of rice paddy fields. Previous studies by Frontier have
demonstrated that wetlands contain a higher bird diversity than the paddy fields. This is
supported by data from Europe which showed that before wetland restoration paddy field
sites had a reduction of birds observed foraging and roosting in the habitat by a factor of 12
(LIFE 2007).
This study aims to quantify the effects of human disturbance on physical habitat structure,
bird biodiversity and species richness, across a range of habitats including wetlands, forest,
cattle grazing sites and coastal forest, using standardised line transects and repeated
surveys to compare the habitat and disturbance levels to one another.
Hypotheses:
1. Biodiversity of bird communities will be negatively correlated with anthropogenic
disturbance.
2. Due to their importance for bird communities the wetlands will have the highest
species richness and biodiversity.
3. Habitats that are experiencing higher disturbance ratings will have smaller tree
height, circumference and a higher % of bare ground than those with lower
disturbance rating.
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4. Observers are more likely to record birds flying within the habitats than those that
are perched in vegetation.
3.3.3 Methods
Bird Survey Methodology
Based on previous studies conducted by Frontier in the area, we monitored biodiversity and
abundance in five habitat types, namely Coastal (C), Rice Paddy Fields (PF), Cattle Grazing
(CG), Wetlands (W), and Forest (F). As well as the eight transects previously established, we
created an additional two, so that each habitat type contained a total of two transects.
All transects were standardized to 300m using a GPS. Line transects were used to reduce the
risk of double counting, with a fixed width of 25m at either side of the line. Bird surveys
were conducted twice monthly (am, pm) for each transect. In keeping with previous reports,
surveys were carried out once in the morning at any time between 06:00-07:00, and in the
afternoon between 16:00 and 17:00.
Each transect was walked by a minimum of two observers trained in bird identification, to
ensure that one observer could record all birds sighted. Prior to beginning the survey,
weather variables such as precipitation, wind and cloud cover were estimated. Precipitation
and wind were estimated on a scale from 0 (none) -4 (very strong). Surveys were not
conducted in very strong wind or heavy rain.
Observers walked the transect at a steady pace of 2km/ hr, recording species seen, their
count, location and activity. Any birds that we were not able to identify to a species level
were recorded as unidentified and removed from analysis. When possible, birds were
identified by call, however in most cases visual identification was necessary to confirm
species. Data was collected continuously over the 300m. Where possible, unknown species
were described or taken photos of for later identification. Location of the bird was recorded
at the first place it was observed, and was grouped into the following bands:
Table 1: Location bands used for surveying bird biodiversity
Location
Ground (G)
Lower Vegetation (LV)
Middle Vegetation (MV)
Upper Vegetation (UV)
Man Made Structure (MM)
Flying (F)
Flying over (FO)
Explanation
<1m
1-3m
>3m
Flying within habitat
Flying above upper canopy height
A broad, universal ethogram was also created in order to record activity type, although
behaviours noted were restricted to “Flying”, “Feeding”, “Landing/Taking off, “Perched”,
“Standing “, “Vocalising” and “Walking”.
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Statistical Analysis
Data analysis was conducted using Estimate S, Microsoft Excel and R statistical software
(version 3.2.2). Pearson’s correlation tests were used to see if there was a significant
relationship between weather variables and species count and abundance. Chi-Squared
tests identified whether there was a significant difference in the locations of birds observed
within all habitats. Chi-Squared tests were also used to establish significant difference
between activities performed when observed, and whether there was a significant
difference in the number of birds observed in October, November and December.
To quantify habitat biodiversity EstimateS v9.2 was used to establish Shannon Weiner,
Simpsons Diversity Index and evenness values. Species richness-based measures were then
used as these are the most sensitive to rare species and the easiest to interpret (Struebig et
al 2011), for this study Chao 1 was used as it was the most accurate. Species richness for all
of the bird communities was estimated using a survey effort of 12 surveys per habitat and a
sample based rarefaction of 100 randomizations, as diversity measurement is dependent on
sample size (Struebig et al 2011). This allowed the production of rarefaction curves for each
habitat. The species similarity between habitats was calculated using the MarczewskiSteinhaus index.
Habitat Survey methodology
Our habitat survey was designed following similar methodology as Shahabuddin and
Kumar’s work on anthropogenic disturbance and bird communities (2006). We carried out
surveys of habitat characteristics for eight of our ten transects (two coastal transects were
unsuitable for assessment). 10m square quadrats were established at 100m intervals along
the transect. Thus a total of 48 plots were marked inside the study site. In each plot, we
collected measurements on vegetation structure and disturbance indicators (Shahabuddin
& Kumar, 2006). Habitat variables measured include the number of trees present in the
quadrats with a circumference at breast height of more than 20cm, the average tree
circumference at breast height, average tree height, average shrub height, canopy cover,
and ground structure. Ground structure was measured using a 0.7m2 quadrat placed at 5
randomly assigned points at each site. In each case, the ground composition (bare ground,
grass, herb, leaf litter, water) was noted at 10cm intervals, and a percentage for each
vegetation type was calculated over the whole transect. Tree height was measured using a
clinometer. Percentage canopy cover was estimated at the centre of each quadrat for lower
canopy (<1m), middle canopy (1-3m) and upper canopy (>3m) layers.
Anthropogenic disturbance was quantified based on indicators of biomass extraction
identified in Shahabuddin and Kumar (2006). Four variables were chosen to show how
intensely the site was used for grazing and fuelwood extraction by local people. Disturbance
indicators included the average scale of lopping from trees (0-4), and the total number of
dung pats, human trails, and charcoal pits within the quadrat. The lopping score for each
tree was measured from 0 – 4 as follows: 0, no lopping; 1, rudimentary signs of lopping; 2,
up to half of the main branches lopped; 3, more than half of the main branches lopped; 4,
the tree reduced to a stump (Shahabuddin & Kumar, 2006). Lopping scale was then
calculated using the mean of the lopping score for each site. For each transect, the totals of
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the four quantitative indicators were averaged to create a disturbance index, so as to
demonstrate the combined effect of various anthropogenic activities on the habitat
(Shahabuddin & Kumar, 2006).
Statistical analysis
Data analysis was conducted using Microsoft Excel and R statistical software. All habitat
characteristics collected over the six sites were averaged for each transect for comparison.
Pearson’s correlation tests were used to correlate habitat variables across all transects with
biodiversity and disturbance indices, and to correlate biodiversity with disturbance.
3.3.4 Results
Species Accumulation Curves
The species accumulation curves for each habitat are presented below. None of the surveys
show a clear asymptote in the curve after 12 samples (Figure 1), this indicates that more
survey effort is required in each of the habitats to ensure that all of the most common
species are recorded. As not all of the habitats had 12 samples total we can compare
species richness at 11 samples. The site with the highest total number of observed species
was the wetlands, with 38 compared to Cattle Grazing, which scored the least with 26
species observed at 11 samples.
40
38
36
34
32
30
Number of Species
28
26
24
22
CG
20
C
18
F
16
PF
14
W
12
10
8
6
4
2
0
0
1
2
3
4
5
6
7
8
9
10
11
12
13
Number of Samples
Figure 1: Sample based rarefied species accumulation curves for bird species in Cattle
Grazing (CG), Coastal (C), Forest (F),Paddy Fields (PF) and Wetlands (W) habitats generated
in EstimateS.
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Species Diversity
The wetlands had the highest Shannon-Weiner value of 2.91 for any of the sites in this
study, this was reflected in the estimated true species richness which was also highest in the
wetlands (Chao1: 52.11). The habitat with the least observed biodiversity was the forest
(Shannon Weiner: 2.58), however the estimated true species richness was higher (Chao1:
49.69) than the cattle grazing (Chao1: 33.36) and coastal (Chao1: 47.05) habitats. This
indicates that despite the forest and cattle grazing habitats having larger Shannon Weiner
values (Table 2), the estimated true species richness based on abundance of the recorded
individuals is higher in the forest.
Table 2: Summary statistics for bird community biodiversity comparing habitats.
Simpsons
Habitat
Shannon Weiner Value
Chao 1
Diversity Index Evenness
Cattle Grazing
2.73
33.36
0.91
0.39
Forest
2.58
49.96
0.92
0.37
Coastal
2.85
47.05
0.86
0.25
Wetlands
2.91
52.11
0.89
0.29
Paddy Field
2.63
48.61
0.92
0.33
All of the habitats had very high species diversity as measured by Simpsons diversity index,
with a difference of 0.08 between the highest diversity and the lowest (Figure 2). The
habitats with the highest species diversity were coastal and wetlands, with a Simpsons
diversity index of 0.92. However, the abundance of each bird species was less evenly
distributed than Cattle Grazing which had the highest observed evenness value (0.39)
(Figure 2). The remaining scores for Simpsons diversity index and evenness for the other
transects can be found in table 2.
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
CG
C
F
Simpsons Diversity Index
PF
W
Eveness
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Figure 2: Simpsons diversity index and evenness values for the bird communities Cattle
Grazing (CG), Coastal (C), Forest (F),Paddy Fields (PF) and Wetlands (W) habitats.
There was a total of 60 species observed between 12 transects in the six different habitats
around Utende village. The habitat with the most species observed was the wetlands with
38 species recorded, compared to cattle grazing which had the least species observed with a
total of 27 species.
The most commonly recorded species was the Common Bulbul (Pycnonotus barbatus),
which was observed 94 times in all of the habitats. Other species recoreded in high
abundance include the White Faced Whistling Duck (Dendrocygna viduata) Bronze Manaikin
(Lonchura cucullata), and the House Crow (Corvus splendens). The abundance observed for
the top ten most commonly seen species can be found in table 3.
Table 3: The top 10 recorded species and the number observed in all of the habitats.
Common Name
Scientific name
No. Observed
Common Bulbul
Pycnonotus barbatus
94
White Faced Whistling Duck
Dendrocygna viduata
88
Bronze Mannikin
Lonchura Cucullata
82
House Crow
Corvus splendens
68
Pied Crow
Corvus albus
65
Common Sandpiper
Actitis hypoleucos
63
Black Bellied Starling
Lamprotornis corruscus
56
Village Weaver
Ploceus cucullatus
45
Marsh Sandpiper
Tringa stagnatillis
40
Cattle Egret
Bubulcus ibis
35
A full species list including the IUCN status and habitats they were observed in is provided in
Annex I.
Habitat Rarity
The habitat with the most unique species was the paddy fields, with seven species not
recorded in any of the other habitat. These include birds often found near bodies of water
such as the Malachite kingfisher (Alcedo cristata), along with grassland and bush birds such
as the Fan-tailed Widowbird (Euplectes axillaris). This is likely due to the heterogeneous
nature of the paddy fields habitat, containing a mix of bush and cultivated bodies of water.
In comparison, both the cattle grazing and forest habitats only had two unique species each,
all of which are associated with forest and bush habitats. The remaining habitats and unique
species that are found in them are summarised in table 4.
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Table 4: Summary of species observed only in one habitat and the habitat they were
observed in, both common and scientific names are reported.
Habitat
Cattle Grazing
Cattle Grazing
Coastal
Coastal
Coastal
Coastal
Forest
Forest
Paddy Fields
Paddy Fields
Paddy Fields
Paddy Fields
Paddy Fields
Paddy Fields
Paddy Fields
Wetlands
Wetlands
Wetlands
Common Name
Eastern Bearded Scrub Robin
Collared Dove
Whimbrel
Tambourine Dove
Red Rumped Swallow
Crab Plover
Purple Banded Sunbird
Hadada Ibis
Purple Heron
Pin Tailed Wydah
Palm Nut Vulture
Malachite Kingfisher
Grey Headed Sparrow
Fan-Tailed Widowbird
Burchells coucal
Three Banded Plover
Pale Batis
White Fronted Plover
Scientific Name
Cercotrichas quadrivirgata
Streptopelia decipiens
Numenius phaeophus
Turtur tympanistria
Cecropis daurica
Dromas ardeola
Cinnyris bifasciatus
Bostrychia rara
Ardea purpurea
Vidua macroura
Grypohierax angolensis
Alcedo cristata
Passer griseus
Euplectes axillaris
Centropus burchelli
Charadrius pecuarius
Batis soror
Charadrius marginatus
All of the habitats had relatively high Marczewski-Steinhaus index scores with 0.25
separating the highest from the lowest value, this indicates that all of the habitats have
similar species compositions (Table 5). This is likely due to the habitats being very close to
one another and all experiencing disturbance.
The two habitats with the most shared species were coastal and paddy fields (MSI: 0.71),
this is likely due to both having large bodies of water and being bordered by both bush and
forest. The habitats with the least shared species MSI:0.46 were the coastal and wetland
habitats, this is unexpected as they are structurally similar to the wetlands being reliant on
tides to flood. The remaining habitats and their similarity index values are summarised in
table 5.
18
Table 5: Marczewski-Steinhaus index (MSI) values comparing each of the habitats,
demonstrating which habitats have the most species in common.
First Habitat
Second Habitat Marczewski-Steinhaus index (MSI)
Cattle Grazing
Forest
0.54
Cattle Grazing
Coastal
0.58
Cattle Grazing
Wetlands
0.5
Cattle Grazing
Paddy Fields
0.64
Forest
Coastal
0.6
Forest
Coastal
0.62
Forest
Paddy Fields
0.56
Coastal
Wetlands
0.46
Coastal
Paddy Fields
0.71
Wetlands
Paddy Fields
0.61
Climatic variables
There was no significant correlation between climatic variables (cloud cover, wind and
precipitation) and species count and abundance (Table 6).
Table 6: Pearson’s R2 correlation coefficients and significance of weather variables on
species count and abundance.
Weather Variables Species Count P- Value Abundance
P- Value
Cloud Cover
0.38
0.77
0.04
0.74
Wind
-0.21
0.11
-0.12
0.34
Precipitation
0.14
0.31
0.004
0.97
Observer variables
There is a significant difference in bird observations at different locations (X 2 = 1165.4, df=7,
p= <0.01). Birds were mostly observed during flight, on the ground, or in the upper
vegetation. Birds were rarely counted from an unknown location or on a man-made
structure (Figure 3).
19
F- Flying
FO- Flying Over
G- Ground
LV- Lower Vegetation
MM- Man Made
MV- Middle Vegetation
U- Unknown
UV- Upper Vegetation
Figure 3: The number of observations of birds in all habitats at different locations with key.
Monthly variation
There is a significant difference in bird observations for the months of October, November
and December (X2 = 34.34, df=2, p = <0.01). Most birds were observed in November
(n=512), with the least amount of birds observed during December (n=345).
Habitat Survey Results
The structure of the vegetation and disturbance ratings for all of the habitats is summarised
in table 6. The wetlands and paddy fields had the highest average disturbance values of all
the habitats, this was reflected in the vegetation structure as they also had the smallest
average CBH, average tree height and number of trees recorded (Table 7). The least
disturbed habitat was the forest, the trees were on average 2.3 times larger than the next
tallest habitat cattle grazing as well as having the tallest average shrub height, largest
average CBH and highest percentage of leaf litter (Table 7). The results for the remaining
habitats are summarized in table 7.
Table 7: Summary of the habitat variables recorded during the surveys around Utende in
2015
140.75
Av. % bare
ground
cover
24.95
Av. Leaf
litter cover
%
39.85
99.5
24
45.65
6.16
325.5
36.87
33.48
54.93
13.71
11
570.6
98.87
112.71
47.46
27.04
Transect
Av. Grass
cover %
Av. Herb
cover %
Av. Water
cover %
Forest
18.64
16.56
0
7
44
Av.
Disturbance
Rating
1.5
Wetlands
37.24
2.28
8.1
3
217
5.01
Paddy Fields
16.67
14.62
0
3
126
3
Cattle
22.04
3.55
0
10
66
2.18
Transect
No. Trees
Av.Tree
Height
Av. Shrub
Height
Av. CBH
Forest
21
1329.31
115.66
Wetlands
1
241
Paddy Fields
Cattle
Grazing
10
No. Stumps
No. cow pats
20
Grazing
As described in Table 8, biodiversity is strongly negatively correlated with the number of
trees (r2=-0.98, df=6, p=0.002) and positively correlated with disturbance (r2=0.76, df=6,
p=0.03) in the habitats analysed. No other significant correlations were found between
habitat variables and biodiversity within the habitat, however average tree height was very
close to the significance threshold, and was negatively correlated with biodiversity (r2=-0.67,
df=6, p=0.07)
Habitat disturbance is negatively correlated with average tree circumference (r2=-076, df=6,
p=0.03), showing that disturbance levels are greater in areas containing trees with a smaller
circumference, such as palm trees or young trees. Disturbance is also negatively correlated
with percentage leaf litter cover (r2=-0.74, df=6, p=0.04), suggesting that areas with thicker
or more established vegetation are less disturbed by anthropogenic factors. This theory is
supported by disturbance rating having a negative correlation with number of trees (r2=0.68, df=6, p=0.06) and with upper canopy cover (r2=-0.68, df=6, p=0.06). Disturbance is
positively correlated with %water cover (r2=0.86, df=6, p=0.005).
Table 8: Pearson’s R2 correlation coefficients between habitat variables, biodiversity and
disturbance. ‘*’ indicates significance of p=<0.05, ‘**’ indicates significance of p=<0.01
Habitat Variables
Biodiversity
P-Value
Disturbance
P-Value
No. Trees
-0.98
<0.01**
-0.68
0.06
Av. Circumference
-0.44
0.28
-0.76
<0.05*
Av. Height
-0.67
0.07
-0.67
0.07
Disturbance Rating
0.76
<0.05*
Av. Shrub height
-0.19
0.66
-0.07
0.86
Cover bare ground
0.13
0.66
0.41
0.31
Cover grass
0.57
0.14
0.39
0.35
Cover herb
-0.36
0.38
-0.4
0.33
Cover leaf litter
-0.6
0.12
-0.74
<0.05*
Cover water
0.55
0.15
0.86
<0.01**
Canopy cover lower
-0.13
0.74
-0.09
0.84
Canopy cover mid
0.62
0.62
-0.5
0.21
Canopy cover upper
-0.42
0.29
-0.68
0.06
3.3.5 Discussion
21
For all of the habitats the species richness recorded are likely an underestimate based on
the species accumulation curves, as none of the habitats have reached an asymptote.
Therefore, more survey effort is required to improve the accuracy of the estimates of
species. This will be done in the following phases to ensure that all of the most common
species in each habitat are recorded.
The habitat with the highest species diversity during this study as measured by species
count, Shannon Weiner and Simpson’s diversity indices was the wetlands. This is supported
by previous studies conducted by Frontier Tanzania (Oliver, 2015) and other studies of
wetland habitats globally (LIFE 2007, Ntongani & Andrew 2013). It is estimated that around
12% of globally threatened birds depend on wetland habitat (Bird life international 2014).
This highlights the importance of wetland habitats for bird biodiversity and conservation
(RAMSAR 2012) and provides further support for the qualification for Mafia as a RAMSAR
site.
However, contrary to other studies conducted which found that paddy fields were poor
supporters of bird biodiversity (Oliver,2015. LIFE 2007), this study found that the paddy
fields contained seven species not seen in any of the other habitats. The paddy fields also
supported more species than the much less disturbed forest habitat, as measured by total
species count, numbers of individuals observed, Shannon Wiener and Simpson’s indices
values. This could be due to the habitat being much more open having the lowest average
shrub height of any of the habitats and containing only 10 trees, this makes it more likely for
observers to be able to see birds moving within the habitat and be able to make a positive
identification as demonstrated by the most birds being observed in this study in flight.
Another potential confounding factor is that the paddy fields are located approximately 300
meters from the wetlands, making it likely that birds will transition between both habitats.
Cattle grazing had the least species observed of any of the habitats. This habitat is located
very close the village and is routinely used as a grazing site for cattle and for wood
extraction as shown by having the largest number of stumps present during the habitat
survey (10). This could indicate that overgrazing has caused a reduction in plant growth and
biomass, which can lead to an increase in the maximum temperature during the dry season
(Belsky et al 1999). This can have negative impact on invertebrate communities, reducing
the carrying capacity of the environment. However, other studies have demonstrated that a
high intensity of cattle grazing can cause an increase in bird and insect abundance by
creating a more heterogeneous habitat of differing successional stages (LIFE,2007). To
establish if cattle grazing is having an impact on bird abundance by reducing invertebrate
abundance, future studies would need to be conducted on the invertebrate communities in
the habitats around Utende.
The habitat with the highest average disturbance rating was the wetlands, with a score of
5.01, the paddy fields also had a high rating of 3.00. This was reflected in the vegetation
structure as the number of trees were the lowest one and ten respectively, the average CBH
was 24cm and 33.48cm and the average tree height 241cm and 325cm. Despite the high
impact of anthropogenic impact including having the highest number of cow pats, and the
least complex vegetation structure, the biodiversity of the bird communities was highest in
22
these transects. Future studies could benefit from incorporating more habitat specific
measures of disturbances for the wetlands and paddy fields compared to the forest and
cattle grazing. As there may be a differences due to natural habitat variation.
A negative correlation between reported biodiversity and the number of trees could
suggest difficulties in observing birds in closed habitats as compared to open habitats,
where birds are more easily seen. The positive correlation between biodiversity and
disturbance could signify this further, although species habitat preference could also be a
factor. This is most likely due to the more open habitat favoring observers in positively
identifying species, and conservation of the wetlands should still remain a priority due to
their important role in avifauna biodiversity (Ntongai & Andrew 2013).
Biodiversity of bird communities was significantly positively correlated with disturbance
(p=0.002) and significantly negatively correlated with the number of trees (p=0.03), this
finding is not supported by other studies such as Ntongani & Andrew (2013), Hassan et al
(2013) and Shahabuddin & Kumar (2006), whodemonstrated that habitats with higher
disturbance had significant decreases in bird community biodiversity. The most likely reason
for this observation is observer bias, as staff and volunteers are here for relatively short
periods of time and despite identification tests being carried the skills required to
effectively, bird surveying takes a lot of practice (Farnsworth et al 2005)
Bird calls were not used for identification in this study as a reliable database wasn’t
available. Future studies would benefit from using sound surveys as it makes positive
identification of species easier in dense habitats such as the forest and could explain why
bird community biodiversity values were lower in the most pristine habitat surveyed.
Conclusions
1. Bird community biodiversity was significantly positively correlated with disturbance
(p=<0.05), this is most likely due to the effects of habitat density on the ability of
observers to accurately detect and identify bird species.
2. Despite being heavily disturbed thewetlands supported the most species of any of
the habitats, and had the highest species diversity measures. This provides further
support for the requirement of wetland habitat to protected, due to its significant
role for global avifauna biodiversity.
3. Disturbance significantly reduced the average circumference and the percentage of
the ground covered by leaf litter (p=<0.05). Tree height (p=0.06) and the number of
trees (p=0.07) were very close to the significance threshold. This demonstrated that
disturbance was having a noticeable effect on habitat structure, potentially reducing
the suitable habitat for some birds by shifting habitats to more open systems.
4. Observers were significantly more likely to observe and successfully record birds in
flight (p=<0.01) than those perching in vegetation. This is the most likely reason for
bird community biodiversity being positively correlated with disturbance in this
study. To counteract this identification using calls could be used in future studies
providing a reliable database of calls can be found.
23
3.4.0 A socio-economic survey of hippo-human conflict in Ndagoni, Tanzania
3.4.1 Abstract
The common hippopotamus (Hippopotamus amphibious) is categorized as Vulnerable on
the IUCN Red List. The species faces the threat of considerable pressure from habitat loss
for agricultural development, as well as being hunted for meat, ivory, and in retaliation for
crop raiding. Crop damage by hippos and other wildlife can be significantly detrimental to
local farmers, causing great economic difficulties and consequent possible retaliation. In this
study Frontier investigated the human hippopotamus conflict in Ndagoni, Mafia, to assess
the economic and social impact of the hippos on landowners and workers. also In addition,
local opinion was sought on management strategies for minimising human hippo conflict in
the future. A high frequency of crop raiding was found in the area compared to similar
studies in Tanzania. The only hippo deterrent used by the respondents was to make noise.
Here, the potential alternative methods to prevent crop raiding are discussed, with the aim
of conserving the small hippo population on the island.
3.4.2 Introduction
The common hippopotamus Hippopotamus amphibious is categorized as Vulnerable on the
IUCN Red List. The species faces the threat of considerable pressure from habitat loss for
agricultural development, as well as being hunted for meat, ivory, and in retaliation for crop
raiding (Vega, 1995). It has been predicted that a level of hunting of 1% could lead to high
population declines over the next 30 to 40 years (Lewison, 2007). Eastern Africa holds the
largest populations of the common hippopotamus and forms a conservation stronghold for
the species, despite large population decline in the Democratic Republic of Congo (Lewison
& Oliver, 2008).
The reliance of the common hippo on freshwater habitats increases the species’ proximity
to human populations and can lead to human wildlife conflict, particularly in times of
drought when there is a greater demand for resources. By 2008, ten countries in Africa had
reported growing numbers of hippo-human conflict, leading to an increased amount of
human mortalities (Lewison & Oliver, 2008). Crop damage by hippos and other wildlife can
be significantly detrimental to local farmers, causing great economic difficulties and
consequent possible retaliation. In this study we investigated the human hippopotamus
conflict to assess the economic and social impact of the hippos on landowners and workers,
as well as their attitudes towards them and past instances of conflict. We also sought local
opinion on management strategies for minimising human hippo conflict in the future.
The study aims to complement and provide a point of comparison with a previous socioeconomic survey on crop damage and conflict in Ruaha National Park, Tanzania (Kendall,
2011). Kendall (2011) described hippo crop raiding as occurring once or twice per year,
predominantly during the wet season (Kendall, 2011). The study further identified a positive
24
correlation between crop raiding and the proximity of the farm to the river. By studying
hippo human conflict in a different area of Tanzania, we can gain a more comprehensive
understanding of the problem. In comparison to the previous study, the study site and
hippo population in Ndagoni, Mafia Island is much smaller, with a known localised
population of approximately 20 individuals. This is well below the minimum viable
population size for the species, which is 500 individuals (Lewison & Oliver, 2008). The small
and isolated hippo population is therefore extremely vulnerable to extinction through
hunting, retaliation for crop raiding, or other conflict with humans. In order to conserve this
population in the future, it is important to investigate the relationship between the hippos
and the local famers.
3.4.3 Methodology
Data Collection
A socio-economic survey was conducted based on the questionnaire used by Kendall (2011)
(Annex II). Six farmers with land based around the hippo population in Ndagoni, Mafia
consented to take part in the survey, which was briefly described as a study of crop raiding
and hippo related issues in the area. Using a translator, all questions were asked to the
group in Swahili and respondents were encouraged to fill in their own questionnaires.
Responses were then translated back to English and recorded for analysis. The
questionnaire totaled 42 questions and the group interview lasted approximately 120
minutes. The survey included questions about the socio economic status of the interviewee,
agricultural characteristics of the farm, economic issues with crop damage in general, and
with hippos in particular. Based on Kendall’s questionnaire, farmers were asked to describe
the stage of plant growth when crops were raided. Plants were categorised as seedlings,
intermediate (larger than half a metre but not harvestable) and mature (Kendall, 2011).
Participants were asked about the effectiveness of the techniques they used to discourage
hippo crop raiding, and what more could be done to protect crops and people from the
threat of hippos. They were also questioned about the possible benefits of maintaining the
hippo population in terms of tourism.
Data Analysis
Data was compiled and analysed using Microsoft Excel software. Survey responses are
presented as the percentage of people giving response to a given question. NA values were
omitted in analysis due to the small sample size. Pie carts and bar graphs were used to
illustrate comparisons where appropriate.
3.4.4 Results
100% of respondents harvested their crops for personal consumption. Farmers grew
multiple crops, including rice (100%), cassava (67%), potato (67%), spinach (67%), tomato
(33%), and onion (6%). All respondents were the primary workers on their fields, spending
over 20 hours in their fields daily during planting and harvest times. Crop raiding was not
identified as a problem when growing crops, though the main pests damaging crops were
defined as birds (42%) and hippos (33%) (Figure 1).
25
The number of crop raids on fields by hippos was reported as comparatively high as
compared to Kendall (Figure 2), with 75% of respondents reporting the occurrence of hippo
crop raids three times or over per year, as compared to 27% in Kendall’s study.
Respondents (%)
Comparison of Crop Raiding Frequency
80
60
40
Kendall
20
This study
0
1 or 2
3+
No. of crop raids annually
Figure 1 Animals responsible for crop damage (%) Figure 2. Comparison of annual crop
raiding frequency between Kendall’s study in Ruaha National Park (2011) and our study on
Mafia.
Hippo occurence was identified predominantly by footprints (83%), as well as actually
sighting the hippo (33%) and dung (33%). All respondents reported crop raids happening at
night, and most frequently during the rainy months of March and April. The height of the
plants when raided most by hippos was reported as intermediate (larger than half a metre
but not yet harvestable)in all cases. In terms of crop preference, 50% of respondents
reported no specific preference, and 67% reported a preference to rice crops. All
respondents reported that both hippo numbers and crop raid frequency has stayed the
same or increased in the last five years. The hippo deterrent method utilised by all
participants was to make noise (100%). When asked why they don’t do more to protect
their crops, 83% of respondents claimed that they did not have sufficient time or energy to
do so. All participants advocated building fences in the future as a way to prevent crop
raiding, if they could afford it. Though all respondents agreed that no action against the
hippo needs to be taken when they damage crops, they thought that the government
should either supply or help build fences to protect crops against the hippos. The
respondents did report benefits to having hippos around their land, as they could bring
more customers and money to the village, however their economic benefits were limited as
they did not draw much business from tourism in the area.
100% of respondents wanted to see the hippo population decrease over the next five years,
their reasoning being that they are a threat to human life as well as farmers’ crops. The last
known hippo attack on a human in the area was on the 18 th of September 1998, when a
hippo killed a human and was consequently shot. All participants were of the opinion that
hippo attacks on humans were preventable through collaboration with the government.
3.4.5 Discussion
26
The survey method used in our study was a group interview, with each participant
completing their own questionnaire. This method had the advantage being more efficient
for translation, however there is also the possibility of bias in that answers were sometimes
discussed within the group. Small sample size potentially reduces the power of the study, so
it may be beneficial to investigate the area for any other farms affected by hippos in future
study. All of the farmers in our study are subsistence farmers and are therefore likely to
suffer great effects from crop damage on their land.
In comparison to Kendall’s study (2011), there was a much greater annual frequency of crop
raids by hippos in Mafia than in Ruaha National Park. Possible reasons for this could be that
there is a relatively high density of hippos within a localized area on the island, whereas the
study site in Kendall’s research was a much larger area. Our study site is not located within
the protected land of the Mafia Island Marine Park, so there are no restrictions or
limitations on the location of farms. In Ruaha National Park, farms may be located at greater
distances from each other, and from habitats with dense hippo populations. Due to issues
with translation, we were unable to visit individual farms. Consequently we could not
establish the distances between farms, nor could we measure the distance of each farm
from the river. This data should be recorded in future studies, to see if there is a correlation
between proximity to the river and crop raiding. However, all participants in our study
recorded a high frequency of hippo crop raids.
In accordance with Kendall’s study, and with the life history of the species, crop raiding
occurred mainly at night, and predominantly in the wet season when the river floods and
comes nearer to the farms. The reported crop preference of hippos in our study varied
between no specific crop and rice. This ambivalence is in accordance with previous studies,
which have found that hippos favoured rice (Eltringham, 1999), maize (Mkanda &
Kumchedwa, 1997), or both equally (Kendall, 2011). The preference for rice in our study
could also be due to the fact that all of the participants grew rice crops, increasing the
likelihood of this crop type being damaged.
The only hippo deterrent used by the respondents was to make noise. This method has the
obvious disadvantages of being unsafe, as it increases the potential for human wildlife
conflict. It also necessitates constant human presence, which could cause economic or
social problems for landowners, for example if a child could not attend school because of
crop guarding (Kendall, 2011). All respondents maintained that a different method was
necessary to prevent crop damage. They advocated building a fence as the best method to
do this. The use of a fence to protect crops would be relatively inexpensive to construct,
however there is no evidence to suggest that fencing would successfully deter the hippos
from the crops. Different types of fences were tested in a study of crop raiding elephants
(Thouless and Sakwa, 1994), and they found that a simple fence with a single electric wire
on top was ineffective, as were stone walls and twelve strand electric fences. This indicates
that fencing may not be the most efficient option for crop protection.
Digging trenches may be a more practical alternative deterrent. They have proved to be
effective for elephants in the past (Lock, 1972), and could be problematic for hippos to
traverse. A possible disadvantage to this method is that trenches may be problematic to
maintain in wetlands, as water could cause the trenches to fill with soil and become
27
ineffective (Nyhus, 2000). Regular maintenance would be necessary to ensure maximum
effectiveness of the barrier (Thapa, 2010). As we can see from the results, crop damage is
not caused exclusively by hippos, but is also perpetrated by birds and monkeys. It therefore
follows that any preventative measure to protect crops should be aimed at multiple pest
species for maximum efficiency. A disadvantage to building fences or digging trenches is
that they are unlikely to deter other crop damaging pests. Further research is recommended
to find a barrier or combination of barriers appropriate to multiple species.
Respondents seemed positive about the potential for ecotourism in the area, particularly if
they could charge tourists a fee to see the hippos (similar to the Mafia Island Marine Park).
They maintained that there wasn’t much business from tourism in the area at present.
Promotion of the site as a tourist attraction could provide an alternative income for the
landowners and encourage positive attitudes towards the hippo population, reducing the
possibility of the human-wildlife conflict.
4.0 Proposed scientific programme for next phase
4.1 Proposed research work for next phase
Continuing monitoring of bird community biodiversity and abundance in the habitats
around Utende is vital to improve understanding of how the communities are changing
through time and with regards to season. This, when combined with the habitat surveys
conducted in the previous phase, will improve knowledge of how disturbance and habitat
structure is effecting bird communities on Mafia. This phase we were able to demonstrate
that despite disturbance being high in the wetlands and paddy fields, bird community
biodiversity was still high and seemingly unaffected. With an improvement in methodology
using bird calls to identify species as well as visual identification, this will reduce some of the
observer bias reported in this phase.
28
The socio-economic survey of the attitudes of locals to hippo-human wildlife conflict,
concluded that whilst having negative attitudes towards the small hippo population they
would benefit from being able to protect their crops which as subsistence farmers they
depend on for food. They could see the potential positives of hippo tourism, this could
provide an alternative sense of income and improve their attitudes towards them. Following
on from this to try and build a lasting and valuable project we will begin applying for grants
to secure funding to try and build fences and ditches to protect the crops.
The resumption of the mangrove health surveys with improved methodology and combining
this with surveying fish biodiversity in the mangroves to investigate whether mangrove
health is affecting fish biodiversity. The most benefit will be gained if surveys can be
conducted in differing use zones, to see if the introduction of the use zones by MIMP is
providing adequate protection to both the habitat and fish biodiversity which the locals
depend on for their livelihood.
A local farmer is planning to release juvenile mangrove crabs (Sycalla sycalla) to try and
boost their populations as they have declined recently affecting local fishermen. We will
begin conducting active surveys of the mangroves before he begins to release them, and
continue after he begins to see if releasing juveniles into the mangroves is affecting the
population abundance.
4.2 Potential contributions of future work
The continuation of surveying bird community biodiversity in a range of habitats will allow a
more reliable estimate of species richness, and how it is changing with seasonality and
through time on Mafia island. This is important in terms of global bird biodiversity due to
the designation of the wetlands as part of a RAMSAR site.
By applying for grants and being able to provide potential barriers to prevent hippo crop
raiding, we would be able to study whether ditches and fences are effective or look into
other means of prevent hippo-human wildlife conflict. Furthermore, by being able to
promote hippo tourism we may be able to aid the conservation of a small population and
encourage the local farmers to act as guardians and stakeholders in the hippos future on
Mafia island.
Resuming surveys in the mangroves investigating the link between mangrove health and
fish biodiversity is important as mangroves act as nurseries for many juvenile fish. This will
be valuable if we can compare the different use zones of the marine park to see if the
protection provided by stricter use restrictions affects fish communities and mangrove
health. As the local community are heavily reliant on fishing to provide food and a source of
income, if there was found to be a decline in fish populations correlated with mangrove
health it would aid MIMP by allowing them to alter their SAMPs.
By beginning a project with Ali, the local crab farmer, we can try and attempt to guide his
expanding operation, as he plans to construct pools in areas of wetlands that he owns that
29
are adjacent to the mangroves. As we find out more about how his project is developing we
can tailor our aims to include habitat surveys such as water quality, as well as how releasing
juvenile crabs is affecting the wild population of the mangrove crab which locals also use as
a source of food and income.
References
Begon, M., Townsend, C. & Harper, J. (2006). Ecology: from individuals to ecosystems.
Malden, MA: Blackwell Pub.
Belsky, A. J., A. Matzke, and S. Uselman. 1999. Survey of livestock influences on stream and
riparian ecosystems in the western United States. Journal of Soil and Water Conservation
54(1): 419-431
Brooks, T. M., Mittermeier, R. A, da Fonseca, G. A. B., Gerlach, J., Hoffmann, M., Lamoreux,
J. F., Mittermeier, C. G., Pilgrim, J. D., & Rodrigues, A. S. L. (2006) Global biodiversity
conservation priorities. Science (New York, N.Y.), 313, 58–61.
Bird Life International (2014a) Data Zone: Endemic bird areas - East African coastal forests.
Available at: http://www.birdlife.org/datazone/ebafactsheet.php?id=100 (accessed:
10/12/2014).
30
Bird Life International (2014b) Wetland and Ramsar. Available at:
http://www.birdlife.org/worldwide/policy/wetlands-and-ramsar (Accessed: 10/03/2015).
Burgess, N., de Klerk, H., Fjeldså, J., Crowe, T. & Rahbek, C. 2000. A preliminary assessment
of congruence between biodiversity patterns in Afrotropical forest birds and forest
mammals. Ostrich 71: 286–290.
Caplan, P. (2011) Population and ethnicity. Available at: http://mafiaislandtanzania.gold.ac.uk/population/ (accessed 20 Sep 2014).
Chami, F.A. (1999) The Early Iron Age On Mafia Island And Its Relationship With The
Mainland. Azania, 34, 1-10.
Doggart, N., Perkin, A., Kiure, J., Fjeldså, J., Poynton, J., & Burgess, N. (2006) Changing
places: How the results of new field work in the Rubeho Mountains influence conservation
priorities in the Eastern Arc Mountains of Tanzania. African Journal of Ecology, 44, 134–144.
Eltringham, S.K. (1999) The Hippos. Academic Press, London, UK.
Farnsworth, G. L., Nichols, J. D., Sauer, J. R., Fancy, S. G., Pollock, K. H., Shriner, S. A., &
Simons, T. R. (2005). Statistical approaches to the analysis of point count data: a little extra
information can go a long way. USDA Forest Service General Technical Report PSW–GTR–
191, 735-743.
Goossens, B., Mbwambo, H., Msangi, A., Geysen, D. & Vreysen, M. (2006) Trypanosomosis
Prevalence In Cattle On Mafia Island (Tanzania). Veterinary Parasitology, 139, 74-83.
Greenway, P. J. revised by Rodgers, WA., Wingfield, RJ. & Mwasumbi, LB.(1988). The
vegetation of Mafia Island, Tanzania. Kirkia 13 (1): 197, 238.
Hassan, S. N., Salum, A. R., Rija, A. A., Modest, R., Kideghesho, J. R., & Malata, P. F. (2013).
Human-induced disturbances influence on bird communities of coastal forests in eastern
Tanzania.
Interact (2010) How to stop illegal logging. The magazine of Progressio. Summer 2010.
Johnson, T. H., & Stattersfield, A. J. (1990). A global review of island endemic
birds. Ibis, 132(2), 167-180.
Kendall, C. J. (2011). The spatial and agricultural basis of crop raiding by the vulnerable
common hippopotamus Hippopotamus amphibius around Ruaha National Park,
Tanzania. Oryx, 45(01), 28-34.
Lewison, R (2007) Population responses to natural and human mediated disturbances:
assessing the vulnerability of the common hippopotamus (Hippopotomus amphibious),
African Journal of Ecology, 45, 407-415.
31
Lewison, R. & Oliver, W. (IUCN SSC Hippo Specialist Subgroup). 2008. Hippopotamus
amphibius. The IUCN Red List of Threatened Species 2008:
e.T10103A3163790.http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T10103A3163790.en.
Downloaded on 15 January 2016
LIFE (2007) LIFE and Europe’s wetlands: Restoring a vital ecosystem. European Commission,
LIFE 111.
Lock, J. M. (1972). The effects of hippopotamus grazing on grasslands. The Journal of
Ecology, 445-467.
Mittermeier, R.A., Myers, N., Thomsen, J.B., Fonseca, D.A. & Olivieri, S. (2008) Biodiversity
Hotspots And Major Tropical Wilderness Areas: Approaches To Setting Conservation
Priorities. Conservation Biology, 12, 516-520.
Mittermeier, R. A., Gil, P. R., Hoffman, M., Pilgrim, J., Brooks, T., Mittermeier, C. G.,
Lamoreux, J., & da Fonseca, G. A. B., (2005) Hotspots revisited: earth’s biologically richest
and most threatened terrestrial ecoregions. Conservation International, Washington, DC.
Mkanda, F.X. & Kumchedwa, B. (1997) Relationship between crop damage by hippopotamus
(Hippopotamus amphibius L.) and farmer complaints in the elephant marsh. Journal of
African Zoology, 111, 27–38.
Myers, N., Mittermeier, R.A., Mittermeier, C.G., da Fonseca, G.A.B. & Kent, J. (2000)
Biodiversity Hotspots For Conservation Priorities. Nature, 403, 853-858.
Mwalyosi, B. (2002). Management of the Rufiji - Delta as a wetland, 115–124.
Ntongani, W.A and Andrew, S.M. (2013) Bird species composition and diversity in habitats
with different disturbance histories at Kilombero wetland, Tanzania. Open Journal of
Ecology 3, 482-488.
Nyhus, P. & Sumianto, R. (2000), Crop raiding elephants and conservation implications at
Way Kambas National Park, Sumatra, Indonesia. Oryx, 34(04), 262-274.
Oliver, K. (2015). Frontier TZF Phase 151 Science Report. London, United Kingdom.
RAMSAR (2012) The Annotated Ramsar List: United Republic of Tanzania. Available at:
http://www.ramsar.org/cda/ (accessed 20 Sep 2014).
Rubens, J and Kazimoto, S (2003) Mafia Island: Demonstration case. Application of the
WPCA- Marine/WWF. Guide book on evaluating effective management in MPA’s.
32
Scharlemann, J. P .W., Green, R. E., & Balmford, A. (2004) Land-use trends in Endemic Bird
Areas: Global expansion of agriculture in areas of high conservation value. Global Change
Biology, 10, 2046–2051.
Şekercioğlu, Ç. H., Daily, G. C., & Ehrlich, P. R. (2004). Ecosystem consequences of bird
declines. Proceedings of the National Academy of Sciences, 101(52), 18042-18047.
Shahabuddin, G., & Kumar, R. (2006). Influence of anthropogenic disturbance on bird
communities in a tropical dry forest: role of vegetation structure. Animal Conservation, 9(4),
404–413.
Struebig, Matthew J., et al. "Parallel declines in species and genetic diversity in tropical
forest fragments." Ecology Letters 14.6 (2011): 582-590.
Taylor, M., Ravilious, C. & Green, E.P. (2003) Mangroves of East Africa. In. UNEP World
Conservation Monitoring Centre.
Thapa,V. (2010) “Habitat fragmentation by land-use change: one-horned rhinoceros in
Nepal and red-cockaded woodpecker in Texas” MSc Thesis, University of Texas.1
Thouless, C. R., Sakwa, J. (1995). Shocking elephants: fences and crop raiders in Laikipia
District, Kenya. Biological conservation, 72(1), 99-107.
Vega, L. (1995). The hippo, threatened due to ivory trade. Quercus III, Mayo.
Williams, P. H., Burgess, N. D., & Rahbek, C. (2000) Flagship species, ecological
complementarity and conserving the diversity of mammals and birds in sub‐Saharan
Africa. Animal Conservation, 3(3), 249-260.
1
Reference from internal report on hippo crop raiding. Reference missing in report.
33
6.0 Annexes
6.1 Annex I
Annex 1: Species list of birds, their IUCN status and which habitats (Cattle Grazing (CG),
Coastal (C), Forest (F),Paddy Fields (PF) and Wetlands (W)). They were recorded in during
phase 154.
Species
Latin name
IUCN Status
African Green pigeon
Treron calva
African Palm Swift
Cypsiurus parvus
African paradise flycatcher
Terpsiphone virdis
Amethyst sunbird
Nectarinia amethystina
Black Backed Puffback
Dryoscopus cubla
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Habitat
Observed
CG, F, W
CG, F, C,
W, P
W
CG, F, C,
W, P
CG, F, C,
W, P
34
Black bellied starling
Lamprotornis corruscus
Black Headed-Apalis
Apalis melanocephala
Black Heron
Egretta ardesiaca
Black Kite
Milvus migrans
Blue-Cheeked Bee eater
Merops persicus
Broad billed roller
Eurystomus glaucurus
Bronze Mannikin
Lonchura culcullata
Burchells coucal
Centropus burchelli
Cattle egret
Bubucus ibis
Collared Dove
Streptopelia decipiens
Collared sunbird
Anthreptes collaris
Common Bulbul
Pycnonotus barbatus
Common sandpiper
Actitis hypoleucos
Crab plover
Dromas ardeola
Dimorphic egret
Egretta dimorpha
Domestic Chicken
Gallus gallus domesticus
Eastern Bearded Scrub
Robin
Emerald spotted Wood
dove
Fan-Tailed Widowbird
Cercotrichas quadrivirgata
Grassland Pipit
Anthus cinnamomeus
Grey Headed sparrow
Passer griseus
Hadada Ibis
Bostrychia rara
House Crow
Corvus splendens
Laughing Dove
Streptopelia senegalensis
Turtur chalcospilos
Euplectes axillaris
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Not
Assessed
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
CG, F, C,
W, P
F, C, P
C
F, C, W
F, C, P
F, C, W, P
CG, F, C,
W, P
P
F, P
CG
CG, F, W, P
CG, F, C,
W, P
F, C, W
C
C, W
CG, F
CG
F, W, P
P
CG, W, P
P
F
CG, F, C,
W, P
F, C, W, P
35
Lesser striped swallow
Cecropis abyssinica
Lilac Breasted Roller
Coracias caudatus
Little Egret
Egretta garzetta
Lizard Buzzard
Kaupifalco monogrammicus
Madagascan bee-eater
Merops superciliosus
Malachite Kingfisher
Alcedo cristata
Marsh sandpiper
Tringa stagnatilis
Olive sunbird
Nectarinia olivacea
Pale batis
Batis soror
Palm nut vulture
Grypohierax angolensis
Pied Crow
Corvus albus
Pied Kingfisher
Ceryle rudis
Pin tailed Wydah
Vidua macroura
Purple banded sunbird
Cinnyris bifasciatus
Purple Heron
Ardea purpurea
Red Eyed Dove
Streptopelia semitorquata
Red-Rumped swallow
Cecropis daurica
Ring-necked Dove
Streptopelia capicola
Common Scimitarbill
Rhinopomastus cyanomelus
Spotted flycatcher
Muscicapa striata
Striated Heron
Butorides striata
Tambourine dove
Turtur tympanistria
Three banded plover
Charadrius pecuarius
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
CG, F C, P
CG, W, P
C, W
P, F
P, W
P
C, W
CG, F, C, W
W
P
CG, C, W, P
CG, W
P
F
P
CG, W
C
CG, C, W, P
CG, C, W
CG, C, W
C, W
C
W
36
Village Weaver
Ploceus melanocephalus
Whimbrel
Numenius phaeophus
White Faced Whistling
Duck
White fronted plover
Dendrocygna viduata
Wire tailed swallow
Hirundo smithii
Yellow-Rumped Tinkerbird
Pogoniulusbilineatus
Zanzibar Sombre Greenbul
Andropadus importunus
Zitting Cisticola
Cisticola juncidis
Charadrius marginatus
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
Least
Concern
F, W, P
C
W, P
W
F, P
CG, C, W, F
CG, C, W, P
CG, F, C,
W, P
6.2 Annex II
Annex II: The questionnaire used for the socio-economic hippo survey
 Verbal consent received to conduct interview
 Consent received to record interview
Date
Village
Questionnaire #
Interviewer(s)
GPS of House
S
E
Other people present
GPS of Farm
S
E
Habitat Surrounding Farm (Was this verified by interviewer?  Yes
 Forest
 River
 Housing
 Other Farms
GPS of Raided Site
S
E
No):
37
 Other (specify)________________________________________________________
Distance to the river? _____________ Which river? ____________________________
Socio-economic Information (of Interviewee)
1. Are you the head of the household?
 Yes
No
2. What is the size of your household? _________________
3. What are your main sources of income?
 Agriculture
 Livestock
 Fishing
 Selling Things
 Job
 Other (specify) ____________________________________
4. Who owns the land where you farm?
 Interviewee
 Other (specify whom) ___________________________________________
5.
a. How many sacks of crops do you grow each year? __________________
b. How much do you sell? _______________________
c. How much of your crop do you and your family eat? ________________
Agricultural characteristics
6. How many acres is your land? _______________________________________
7. How long does it take to walk to your farm from your home (minutes)?
____________________
8. What types of crops do you grow?
How much of the field is each crop (acres)?
How much is a sack of each crop worth?
Crop Grown
Value per sack
How much of the Field?
38
9. Are your crops irrigated?
 Yes
 No
How much is irrigated? ________________________________
10. Are you the primary worker on your fields?
 Yes
 No
If yes, during the planting up to harvest time, how many hours a day do you spend in the
fields?
 less than 1 hour
 1- 5 hours
 6 -10 hours
 11-15 hours
 16 – 20 hours
 More than 20 hours
Crop Damage
11. What problems do you encounter when growing your crops?
________________________________________________________________________
__________________________________________________________________
12. Of the following animals, which are problems in terms of crop damage in your crops?
Hippo
 Yes
 No
Monkey
 Yes
 No
Birds
 Yes
 No
Bushpig
 Yes
 No
Are there any other animals that cause problems in the field?
____________________________________________________________________
13. Which animal causes the most crop damage? _____________________________
Hippos
14. What do you think about hippos?
 Like
 Dislike
 Indifferent
 Unsure
a. Why? _____________________________________________________
__________________________________________________________________
15. Are you afraid of hippos?
39
16. When was the last time hippos damaged or raided your crops?
 This year
 Last year
 2-5 years ago
 More than 5 years ago
If not this year or last year, skip to question 24.
17. How often do hippos raid your crops this year/last year (depending on answer to qu.
16)?
 Once
 Twice
 Three times
 More than three times
18. How much of your crops are/were lost to hippos this year/last year (depending on
answer to qu. 16) in acres?
_______________________________________________________________
19. How do you know it was hippos that raided your crops?
 Footprints
 See the hippo
 Hippo Dung
 Appearance of damaged vegetation
 Other (specify) ____________________________________
20. What time of day does crop damage from hippos occur?
 Morning
 Afternoon
 Evening
 Night
 No specific time
 Unsure
21. Are there particular months when crop damage from hippos has occurred more
often in the last five years?
________________________________________________________________
22. When crop damage from hippos occurs what age are the crops?
 Seedlings (1.5 feet from ground or less)
 Intermediate (2-3 feet from ground)
 Mature (taller than 3 feet, harvestable)
23. Of the crops you grow, which do hippos feed on?
40
 Rice
 Maize
 Millet
 Groundnut
 Other (specify) ________________________________________________
 No specific crop is preferred
 Unsure
24. Have the number of crop raids by hippos on your farm increased, decreased, or
stayed the same in the last five years?
 Increased
 Decreased
 Stayed the same
 Unsure
25. Have the number of hippos near your village increased, decreased, or stayed the
same in the last five years?
 Increased
 Decreased
 Stayed the same
 Unsure
Deterrent Techniques
26. What do you do to keep hippos away from your crops?
Method
Build fence
What material? ______________
Create ditch/moat
Make noise
Guard crops (Day)
Guard crops (Night)
Pepper plants/pepper oil
Effective?
 Yes  Sometimes No
41
Burn
What do you burn? __________
Other (please specify)
Nothing
If Nothing, ask question 27.
27. Why don’t you protect your crops?
 Not enough time/energy
 Not enough money
 No need
 Protecting crops is not effective
 Dangerous
 Other (specify) ________________________________________________
28. What else could be done to protect crops?
________________________________________________________________________
__________________________________________________________________
29. How much time per day in planting to harvest time, do you spend trying to keep
animals away from your crops?
 Less than 1 hour
 1-5 hours
 6-10 hours
 11-15 hours
 16-20 hours
 More than 20 hours
30. How much money do you spend trying to keep animals away from your crops each
year?
_________________________________________________________________
31. What should happen when hippos damage crops?
 Nothing
 Trap and move them
 Shoot them
 Farmers should be compensated
 Other (specify) ________________________________________________
If answered shoot to Question 31, then ask Qu. 32 and skip Qu. 33 and 34. If answered
otherwise, skip Qu. 32.
32. If shot would you eat the meat of a hippo?
42
 Yes
 No
If shoot, what else could you use hippos for?
_________________________________________________________________
33. If don’t shoot why use other solution?
________________________________________________________________________
__________________________________________________________
34. Any benefits of having hippos?  Yes
 No
What?
________________________________________________________________________
__________________________________________________________________
35. Have you noticed any hippo tourism in the area?
36. Do you think that hippo tourism could benefit you?
37. What do you want to see happen to the number of hippos in the area in the next five
years?
 Increase
 Decrease
 Stay the same
 Unsure
38. Do you have other problem with hippos besides crop damage?  Yes
Are hippos a threat to human life?  Yes
 No
 No
What are the other problems? __________________________________________
39. Have people ever been attacked by hippos?  Yes
 No
If no, finish survey here.
40. When was the last known attack?
Date_______________________
Time of day__________________
Location______________________
What happened_______________________________________
Result of attack_________________________________________
41. Are hippo attacks on people preventable?
 Yes
 No
43
a. How? __________________________________________________
42. What should happen when hippos attack people?
 Nothing
 Trap and move them
 Shoot them
 Compensation
 Other (specify) ________________________________________________
If answer shoot for Question 42, but not for Question 31, then ask Question 32.
Thanks for your help and participation!
44

Tanzania Forest Conservation Science Report 154

Transcription

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