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Primate and large mammal targeted surveys, Phase II
Bumbuna Hydroelectric Dam,
Sierra Leone: Priority species
August 2017
Jessica Ganas – Swaray, Mimi Arandjelovic, Natalia Bolaños, Genevieve
Campbell, Rosa Garriga, Suzanne Livingstone, Adeline Serckx
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TABLE OF CONTENTS
1 EXECUTIVE SUMMARY ............................................................................................................... 7
2 INTRODUCTION ........................................................................................................................... 10
3 METHODS ....................................................................................................................................... 13
3.1 Study area ................................................................................................................................... 13
3.2 Survey methods .......................................................................................................................... 16
3.2.1 Community interviews ........................................................................................................ 16
3.2.2 Reconnaissance (recce) walks ............................................................................................. 17
3.2.3 Camera trapping .................................................................................................................. 18
3.2.4 Chimpanzee DNA data collection ...................................................................................... 19
3.3 Data analysis .............................................................................................................................. 20
4 RESULTS AND DISCUSSION ...................................................................................................... 23
4.1 Community interviews ............................................................................................................... 23
4.1.1 Species presence ................................................................................................................. 23
4.1.2 Population trends ................................................................................................................ 24
4.1.3 Hunting ............................................................................................................................... 25
4.2 Recces......................................................................................................................................... 27
4.2.1 Overall species presence ..................................................................................................... 27
4.2.2 Human disturbance ............................................................................................................. 30
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4.3 Camera traps ............................................................................................................................... 33
4.4 Priority species ........................................................................................................................... 33
4.4.1 Western Chimpanzees ......................................................................................................... 33
4.4.2 Pygmy Hippos ..................................................................................................................... 49
4.4.3 Black and White Colobus ................................................................................................... 51
4.4.4 Red Colobus ........................................................................................................................ 53
4.4.5 Diana Monkey ..................................................................................................................... 54
4.5 Comparisons of survey data with previous studies .................................................................... 56
4.6 Human activities and priority species ........................................................................................ 58
4.6.1 Hunting ............................................................................................................................... 59
4.6.2 Habitat destruction .............................................................................................................. 59
4.6.3 Crop-raiding ........................................................................................................................ 60
5 SUMMARY / CONCLUSIONS ..................................................................................................... 64
5.1 Overall species composition........................................................ Error! Bookmark not defined.
5.2 Western Chimpanzees ................................................................................................................ 64
5.3 Pygmy Hippos ............................................................................................................................ 65
5.4 Black and White Colobus ........................................................................................................... 66
5.5 Red Colobus and Diana Monkeys .............................................................................................. 66
5.6 Ungulates .................................................................................................................................... 66
5.7 Human disturbance ..................................................................................................................... 67
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6 RECOMMENDATION FOR DRY SEASON 2018 SURVEY .................................................... 68
7 BIBLIOGRAPHY ............................................................................................................................ 71
8 APPENDICES .................................................................................................................................. 76
8.1 Appendix 1. Supplementary maps ............................................................................................. 76
8.2 Appendix 2. Habitat type definitions ......................................................................................... 79
8.3 Appendix 3. A selection of photographs of large mammals captured on the camera traps. ...... 80
8.4 Appendix 4. Photographs of field observations ......................................................................... 85
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TABLE OF FIGURES
Figure A. Study area. . .............................................................................................................................. 15
Figure B. The locations of the four types of data collection. .................................................................... 22
Figure C. Species presence according to interviews. ................................................................................ 23
Figure D. The communities’ perceptions of species populations. ............................................................ 24
Figure E. Communities and hunting activities. ......................................................................................... 26
Figure F. The number of human disturbance activities in the area. .......................................................... 30
Figure G. The distribution of habitat disturbance types across the study site. ......................................... 31
Figure H. Survey effort and human disturbance activities. ...................................................................... 32
Figure I. Recce survey effort and locations of the proposed chimpanzee groups. ................................... 37
Figure J. Recce survey effort and corresponding locations of chimpanzee observations. ....................... 39
Figure K. The locations of chimpanzees in June 2017. ............................................................................ 40
Figure L. A comparison of identified chimpanzee locations from 2014, 2016, and 2017. ...................... 41
Figure M. The number of chimpanzee nests categorized by age. ............................................................ 46
Figure N. The percentage of habitat types each chimpanzee nest was located in. ................................... 46
Figure O. The frequency of tree species used for nesting by chimpanzees. ............................................. 47
Figure P. Locations of Western Chimpanzee evidence. ........................................................................... 48
Figure Q. Locations of Pygmy Hippo evidence........................................................................................ 50
Figure R. Location of Black and White Colobus . .................................................................................... 52
Figure S. Locations of Red colobus surveys ............................................................................................. 53
Figure T. Recce survey effort and three priority species locations. .......................................................... 55
Figure U. Priority species occurrence and human disturbance activities. ................................................ 63
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TABLE OF TABLES
Table 1. A description of each nest age classification .............................................................................. 18
Table 2. A comparison of the results of the three methods used to quantify species presence ................ 28
Table 3. A summary of the different chimpanzee “groups”. .................................................................... 36
Table 4. A comparison of encounter rates conducted for four studies between 2014 – 2017. ................. 57
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1 EXECUTIVE SUMMARY
We conducted targeted baseline surveys for the planned upgrade to the Bumbuna Hydroelectric
Power Plant and corresponding facilities based in Yiben, Northern Sierra Leone focusing on five priority
species of large mammal: the Western Chimpanzee (Pan troglodytes verus), the Red Colobus monkey
(Piliocolobus badius), the Black and White Colobus monkey (Colobus polykomos), the Diana monkey
(Cercopithecus diana), and the Pygmy hippopotamus (Choeropsis liberiensis). This study is to be
completed in two parts: the first phase, the current study (taking place in the wet season, June 2017), and
the second phase, taking place in the dry season in early 2018. Conducting surveys in a wet and a dry
season will give a comprehensive understanding of the presence, abundance, and habitat use of these
priority species and other large mammals within this area and will provide information to inform the
design of mitigations in the Biodiversity Action Plan.
Surveys reported on here took place from 06 June – 28 June 2017. The objectives of the overall
study are to:
1) Improve the understanding of each priority species’ presence, distribution, and habitat use
around the inundation area;
2) For Western Chimpanzees, assess their relative abundance, the number of communities present
and their possible territory size;
3) For Western Chimpanzees and Pygmy Hippos, understand potential corridors that would allow
them to move outside of the inundation area, and
4) Identify threats and their corresponding spatial distribution within the study area.
8
The results presented in this study are the first part of a larger piece of work whereby additional
information will be gathered in the dry season in 2018, and analysis will be conducted with a detailed
habitat map created at the same time as this report (Collins and Mitchard 2017).
In this study, three teams collected data from communities and forests located within the study
area. Data were collected via community interviews, recces, camera traps, and chimpanzee dung collection
for the purposes of genetic analysis.
Interviews with 44 communities around the inundation area reported 24 species of large mammals
ranging near their villages. During field surveys, we quantified the presence of 16 species of large
mammals including the priority species Western Chimpanzees, Pygmy Hippos, and Black and White
Colobus monkeys while camera traps identified 13 species of mammals (including small mammals) on
the camera traps (species quantified using these two methods were not mutually exclusive).
We confirmed the presence of six out of the nine groups of chimpanzees previously documented
in the area and also recorded the presence of chimpanzees in five new areas. Two of those areas were not
investigated during this study period, but will be surveyed in the Wet Season in 2018. Genetic analysis
identified 20 unique adult individuals belonging to potentially four different groups (these same groups
were also identified by nest counts) with a female to male sex ratio of 3:1, which is atypical of what has
been previously reported in past studies. Chimpanzee evidence was primarily found in small patches of
Hillslope and Gallery forests. Our results show that at least one chimpanzee group whose home range is
inside the inundation area will be directly impacted by project activities, while the remaining groups may
be indirectly impacted by competition for resources with people as communities are relocated from the
inundation area to other areas in the greater project area. We recommended avoiding relocating
communities close to chimpanzee areas.
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We documented the presence (direct sighting) of two Black and White Colobus in a small forest
patch approximately 3 km north of the inundation area. This is the first time that presence has been
documented in the area since 2005. Given the likely very low density of this species in the study area, no
communities should be relocated near this forest patch. Although five villages indicated that Red Colobus
still ranged in the area (at low numbers), we were unable to verify its presence in the field. Both Colobus
species are typically restricted to forested areas, so any forest conservation measure that protect Black and
White Colobus, would also by default protect Red Colobus. No villages indicated Diana monkeys ranged
in the area and we were unable to document Diana monkey presence.
We recorded pygmy hippo signs in two areas on the Seli river (inside the inundation area) as well
as three other locations on the Mameli river. Pygmy hippos on the Seli will probably lose important
habitat, including the loss of herbaceous vegetation (their staple food source) near the river, as a result of
the flooding of the inundation area. If flooding is unavoidable in this area, mitigation measures such as
reducing human disturbance (e.g. artisanal mining) as well as conducting sensitization campaigns in the
other areas where pygmy hippos range near the inundation area will be critical for pygmy hippos’ survival.
Human disturbance is relatively high throughout the study area. Signs of human disturbance were
the second most recorded observation on recces, which were primarily conducted in forests. Outside of
the recces, the landscape is dominated by slash and burn agriculture. The most common human
disturbance sign recorded was hunting, following by artisanal gold mining, and logging. Considering
Primates and Pygmy Hippos, up to 58% of respondents in community interviews indicated that they hunt
these species. Addressing the level of human disturbance, in particular in areas where priority species
range will be critical for conservation efforts in the area.
For the 2018 dry season survey, we propose the following actions: 1) Conduct systematic transect
sampling in targeted areas within the study area, based on the current findings of chimpanzee presence to
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quantify population density; 2) Conduct additional recces in areas thought to contain chimpanzees, but
not covered under planned transect surveys. This will give us a better picture of chimpanzee distribution
in order to make informed decisions with community resettlements and fully understand the project’s
impact; 3) Continue to collect chimpanzee dung for genetic analysis, placing priority in areas where we
do not fully understand the number of chimpanzee groups; and 4) Conduct additional recces to survey for
Pygmy hippos, Red Colobus, and Black and White Colobus in targeted areas. These data could then be
used for habitat suitability maps for planning conservation areas and potential movement corridors.
2 INTRODUCTION
The following targeted study aimed to complement data collected as part of the Environmental
Impact Assessment (EIA) for the upgrade to the Bumbuna Hydroelectric Power Plant and corresponding
facilities based in Yiben, in the Koinadugu District, Northern Sierra Leone. Since 1996, there have been
several EIAs examining various areas surrounding the original Bumbuna Dam including what is now
known as the Bumbuna Conservation Area (BCA), sections surrounding the corresponding transmission
line, the Yiben Dam, and areas within and near the Yiben inundation area (Nippon Koei 2007, Samba
2013, Ganas & Garriga 2014, Garriga & Humle 2016, Garriga 2016). These studies documented the
presence of small, medium, and large mammals in these areas, including species of conservation concern
including the Western chimpanzee (Pan troglodytes verus) and the Pygmy hippopotamus (Choeropsis
liberienesis). The current study is intended to re-survey some of these areas to confirm the continued
presence or absence of species previously recorded, and to also include previously unsurveyed areas, in
particular areas outside the inundation area that may potentially be impacted indirectly by project
activities. This survey focuses primarily on five priority species, based on results from Critical Habitat
assessment and Species Prioritisation report (TBC 2017), and which are considered threatened according
the IUCN Red List: The Western Chimpanzee (Critically Endangered), the Pygmy Hippopotamus and
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the Western Red Colobus (Piliocolobus badius, both Endangered) and the Western Black and White
Colobus (Colobus polykomos) and Diana Monkey (Cercopithecus diana, both Vulnerable). It should be
noted that it is likely that the Black and White Colobus and Diana Monkey status will be raised to Critically
Endangered in the near future (IUCN Primate Specialist Group pers. comm. 2017). These complementary
studies are intended to be completed in two parts: the first phase, the current study, taking place in the wet
season, June 2017, and the second phase, taking place in the dry season in early 2018. Conducting surveys
in a wet and a dry season will give a comprehensive understanding of the presence, abundance, and habitat
use of these priority species and other large mammal species within this area.
Objectives:
Focusing on these five priority species, the objectives of this phase (wet season 2017) are:
Western chimpanzees
a) Collect and update information on their distribution and habitat use throughout the study area
b) Assess the number of communities present and their possible territory size
c) To understand any potential corridors that would allow them to move outside of the inundation
area.
d) Use this information to inform further surveys to be conducted in the dry season in 2018.
Pygmy hippos
a) Gain an improved understanding of their presence and distribution, particularly in and around the
inundation area
b) To understand any potential corridors that would allow them to move outside of the inundation
area.
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Red colobus, Black and white colobus, Diana monkeys
a) Gain an improved understanding of their presence and spatial distribution within the study area
For all species:
a) Identify existing threats and their corresponding spatial distribution within the study area
Although we are focused on these priority species, we also aim to quantify information on the
presence/absence of other large mammals such as Buffalo, duikers, and pangolins.
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3 METHODS
3.1 Study area
The study area encompassed the environs surrounding the Bumbuna Hydroelectric Power Plant and
planned Yiben reservoir. A discrete management unit (DMU), a result of a Critical Habitat assessment
conducted by TBC in 2017, was demarcated around these areas serving as an ecological unit and for the
purposes of this study, was used as a basis for determining locations to investigate our research questions
on priority species (Figure A).
The area is characterized by a forest savannah mosaic with a high annual rainfall (2000 – 3000 mm)
concentrated within a 7-month wet season. This begins in May and ends in October with maximum rainfall
of around 600 mm in August. The Seli River is the dominant river system, and the basis for the dam,
running southwest through the study area. The study area is located at the base of the Sula Mountains
with a landscape characterized by moderate to high relief (300 m – 600 m). It is also dominated by human
activities, in particular slash and burn agriculture, with seven habitat types present: Gallery forest,
Hillslope forest, Woodland savannah, Seasonally wet grassland, Agriculture, Freshwater swamp, River
channel community, Inselbergs, and Exposed substrate (Collins & Mitchard 2017). The closest Protected
Area outside of our study area is nearby Loma Mountains National Park. It is home to a relatively high
mammal biodiversity including Pygmy Hippos and Western Chimpanzees (Brnic et al. 2010; Kortenhoven
2009).
The Bumbuna Conservation Area (BCA, 3,532 ha) is small protected area northwest of the
Bumbuna Hydroelectric Project and is included in this study. It was recognized by an Act of Parliament
in 2008 and is managed by the Bumbuna Watershed Management Authority, a semi-autonomous authority
under the Ministry of Energy and Power. The objectives of the BCA include environmental management
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and biodiversity conservation and was created in part to preserve biodiversity in the Bumbuna
Hydroelectric Dam area. A management plan was put into place in 2007 and current activities include
wildlife biomonitoring, including the use of camera traps. It is important to note that Samba (2013)
conducted a large mammal survey in the Bumbuna Conservation Area and found that the abundance and
spatial distribution of large mammals were reduced since a previous Environmental Impact Assessment
in 2006 (Nippon Koei 2007).
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Figure A. Study area.
The DMU was used as a spatial unit of analysis for the critical habitat assessment conducted by TBC in
2017 and represents an ecological unit within which the Hydroelectric Dam project and corresponding
activities could directly and indirectly affect priority species.
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3.2 Survey methods
Surveys took place from 06 June – 28 June 2017. Three teams, consisting of a team leader, two
field assistants, and one to two local guides collected data from communities and forests located within
the study area. Data were collected via community interviews, recces, camera traps, and chimpanzee dung
collection for the purposes of genetic analysis (Figure B).
3.2.1 Community interviews
We conducted 64 structured interviews in 44 villages within the DMU. Because one of the
objectives of the interviews was to gain new information about species presence and distribution in areas
outside of the Yiben inundation area, most of the interviews took place in villages northeast, north and
northwest of the Yiben inundation area (Figure B). Interviews were conducted after first gaining
permission from the village chief. Typically, interviews were with a group of community members,
frequently including farmers and hunters. At the discretion of the research team, there were sometimes
multiple interviews within a village if the village was deemed ‘large’ and data collection would benefit
from gathering further information from a broader cross-section of the community.
During the interviews, we asked about primate, ungulate, and pangolin presence in the community
areas, including their farms (which may be up to 7 km away from the village). Depending on what was
most comfortable for community members, interviews were conducted in a combination of Krio, Kuranko,
and/or Limba. To be as accurate as possible on species identification, we first asked interviewees to list
the animal species observed in the area, and afterwards, provided them with animal guides with pictures
to confirm species identities. A total of 27 medium and large mammal species were presented in the guide,
including one, the African elephant, which was known not to range in the area. This species was presented
to aid in understanding the accuracy of interviewees responses. After confirming priority species were
17
present in the area (Western chimpanzees, Red Colobus monkeys, Black and White Colobus monkeys,
Diana monkeys, and Pygmy hippos) we next asked interviewees to detail where these species were found,
and during which times of the year. This information was then used to direct where research teams would
conduct reconnaissance (recce) walks. Typically, if an interview indicated priority species ranged in the
area, we would return to the village on a later date, and together with a hunter or farmer from the village,
travel to the area where interviewees indicated a priority species ranged and began a recce. We also asked
the communities’ observations on primate group sizes, the population trends of primate species and pygmy
hippos, if these species were hunted, if these species raided their crops, and any polyspecific associations
(interactions/relationships) among different primate species.
3.2.2 Reconnaissance (recce) walks
During this phase of the study, we conducted recce walks to gain a better understanding of the
distribution of priority species, particularly in areas that have not been surveyed in previous studies. These
data will aid in formulating a plan of where systematic transects will be walked during the second phase
of this study in 2018. Recces for this study were not ‘traditional’ recces in which observers walk a path
of least resistance in a pre-determined direction, not varying by more than 40° (Kühl et al. 2008). Since
one of the primary objectives of this study is to gain a better understanding of the priority species
distribution, abundance, and habitat use, we biased recces to place them in areas where these species were
thought to range (drawing on information collecting during community interviews, and as well, where
priority species were indicated to range based on previous studies). Within these areas, every effort was
made to survey across different habitat types and altitudes. During a recce walk, data were collected direct
and indirect presence of primates, ungulates, and pangolins (i.e. direct observations, footprints, dung,
feeding remains, vocalizations, nests, trails), and of human disturbance (e.g. snares, empty gun shell
cartridges, mining, farming, and logging evidence) recording their habitat type and GPS location. Habitat
18
type classifications (Hillslope, Gallery, Woodland, Seasonally wet grassland, Swamp, River channel
community, Inselberg, Agriculture, and Exposed substrate, see Appendix 2 for a description of habitat
types that were developed as part of the habitat mapping aspect of the study area (Collins & Mitchard
2017). Unlike previous studies, we did not collect data on smaller mammal species such as rats,
porcupines, and mongoose as the aim was to focus data collection on priority species.
We collected additional information from chimpanzee nests found along the recce. Each nest was
classified by its age (fresh, recent, old, very old), following Tutin & Fernandez, (1984, Table 1), and when
possible, the species of the tree the nest was located in was recorded. Many times, multiple nests were in
a single tree, or trees that were very close together, and thus one GPS location sometimes represented
multiple nests.
Table 1. A description of each chimpanzee nest age classification (following Tutin & Fernandez
1984)
Nest age classification Description
Fresh Leaves forming the nest are completely green
Recent Leaves forming the nest are changing color; a mixture of green and brown
leaves
Old Leaves forming the nest are brown, but the nest is still entirely formed with
branches
Very old There are no leaves remaining but the nest is still identifiable by broken
branches
3.2.3 Camera trapping
To aid in documenting the presence of western chimpanzees and pygmy hippos, we placed ten
infrared, remotely sensed digital cameras in the study area (Bushnell 14 MP Trophy Cam HD). Eight
cameras were placed near rivers/streams where either local people indicated pygmy hippos have ranged
in the past and/or direct evidence of hippos were found. The remaining two cameras were placed in areas
19
of relatively high chimpanzee nest density. Camera were set between 08 June and 28 June 2017, and were
in the field for an average of 16 days (SD = 1.9 days, Figure B). Cameras were programmed to be
operational 24 hours (including infrared during nighttime hours), set to high sensitivity, and to record
three consecutive photos without delay once triggered. Date, time, and camera ID were stamped on each
photograph. Animals from the photographs were identified following Kingdon (2015).
We recorded the following information from the cameras: 1) # of trap days (one camera at one
location for 24 hrs.), 2) survey effort (total number of trap days for all cameras), and 3) trap success (#
of independent events/100 trap nights). We also calculated 4) # of independent events, which can be
defined as a) consecutive photographs of different species, and b) consecutive photographs of individuals
of the same species taken more than 30 minutes apart.
3.2.4 Chimpanzee DNA data collection
Documenting chimpanzee abundance by recces and transects comes with challenges due to
chimpanzees’ shy nature and low densities as well as inherent impreciseness that comes with collecting
data using indirect methods (i.e. nest counts). Collecting feces and extracting DNA from them is an
accurate and innovative way of identifying and surveying for chimpanzees (Arandjelovic et al. 2010,
2011). The extraction of DNA can aid in identifying the number of chimpanzees and chimpanzee
communities present, their distribution and ranging patterns. To complement data collection on
chimpanzee presence using recce walks, we also collected (fresh) faecal samples found close to
chimpanzee fresh nests when possible, using the 2-step method, which involved collecting and storing
feces in 90% alcohol, and later, in silica gel (Nsubuga et al. 2004). For each sample collected, a GPS
location was recorded. Sometimes, multiple dung samples were located in a small area close together (e.g.
under a single tree), and in these instances, one GPS location represented multiple dung samples.
However, each sample collected had a unique ID.
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During our recce walks, locating fresh nests to collect chimpanzee faeces was a priority. Because
we already have an understanding of where chimpanzees range around the greater Bumbuna environs
(Bumbuna Conservation Area, Kamasapi area, and Masamarandugu/Worowaia area, from Nippon Koei
2007, Samba 2013) one team focused on collecting samples from these three areas. The other two teams
conducted recces in other areas indicated to contain priority species and collected chimpanzee faecal
samples when possible. For all areas in which samples were collected, teams revisited the same area
towards the end of the study to re-sample for faeces to better ascertain community belonging and to
estimate abundance through mark-recapture techniques (Arandjelovic et al. 2010, 2011)
Samples were sent to the Max Planck Institute for Evolutionary Anthropology in Leipzig,
Germany for genetic analysis.
3.3 Data analysis
To assess relative abundance, we calculated an encounter rate by dividing the total number of signs
observed per species by the total length of all recces (km). Signs were recorded as independent if they
were separated by >5 meters. In addition, on the path leading up to the start of the recce, or after the end
of the recce, if we encountered any large mammal or human disturbance sign, we also recorded its
corresponding GPS location, sign type, and habitat type (“ad-lib” data). Ad lib data were not used to
calculate the encounter rate, but were used to calculate overall species presence and overall human
disturbance activities.
In addition to large mammal signs, we also collected data on human disturbance. To analyze all
observed human disturbances (recces, ad-lib, camera traps), we classified human disturbance variables
into four categories: 1) Agricultural activities (domestic animal dung, active farms, and farm huts), 2)
Gold mining (any presence along rivers of mining pits/tools, etc.), 3) Hunting (empty shell cartridges,
21
heard gunshots, and direct observation of guns, hunting paths, pit traps, snares, traps and trap fences) and
4) Logging (multiple logging boards stacked awaiting pickup). It is important to note that because the
study area was a human dominated landscape with many agricultural activities, we did not record evidence
of agriculture outside of the recces, and data on agriculture for the entire DMU is underrepresented.
22
Figure B. Locations of the four types of data collection.
a) Community interviews, b) recce walks, c) camera trapping, and d) chimpanzee dung collection for
genetic analysis.
1=Badala, 2=Bendukoro, 3=Bendukura, 4=Benekorafoo, 5=Diang Sokurella, 6=Fogo, 7=Gbogoroma, 8=Herekoh, 9=Igaia,
10=Kafogo, 11=Kakekoro, 12=Kamabareh, 13=Kamakiya, 14=Kamansu, 15=Kamaron, 16=Kamayeke, 17=Kamayimbo,
18=Kania, 19=Kasaray Kunday, 20=Heremakonokenema, 21=Kodala, 22=Kondenbaia, 23=Konkoba 2, 24=Kormator,
25=Lengekoro, 26=Makekoro, 27=Medina, 28=Sandia, 29=Sarako, 30=Sokurela, 31=Tonkoia, 32=Yara, 33=Yisaia,
34=Konkomba, 35=Worowaia, 36=Kayako 2, 37=Fadugu, 38=Simbek, 39=Kakarma, 40=Kasine, 41=Temne Moria, 42=Diang
Sokurella 2, 43=Siselah, 44=Alusania.
23
4 RESULTS AND DISCUSSION
4.1 Community interviews
4.1.1 Species presence
Of the 44 villages interviewed, 24 species of large mammal were indicated to range in the study
area (those species that were presented in the wildlife guide, Figure C). The most common species said to
be present was the African buffalo, followed by the Red river hog and Maxwell’s duiker.
Four out of the five priority species (Western chimpanzee, Black and White Colobus monkey,
Red Colobus monkey, and Pygmy hippo) were said to be present. No villages reported the Diana monkey
to range around their communities.
Figure C. Species presences according to interviews. Priority species are indicated in red. The
percentage of interviews indicating the presence of each large mammal species ranging in their community
area. Actual number of interviews are indicated at the top of each species’ bar.
42 42 41 41 40 40 3937 36 35
33 32 32
29
2321 20
15 15 1513
108
4
0
10
20
30
40
50
60
70
80
90
100
% in
terv
iew
s
Animal species
24
4.1.2 Population trends
Between 50 and 68% of communities perceived the four priority species (excluding Diana
monkeys which were not thought to range in the area) populations to have declined over time, agreeing
with each species current documented population trend across their range (Humle et al. 2016, Ransom et
al. 2015, Oates et al. 2008; Oates et al 2016, Figure D). Communities indicated that the remaining primate
species populations, Olive baboons, Campbell’s monkeys, Spot-nosed monkeys, Patas monkeys and
Green monkeys (which can be considered more adaptable than the priority species), were actually
increasing.
Figure D. Community perceptions of species populations.
Not all species had corresponding information from every village due to local ranging patterns, and thus
not all answers are equal to the total number of interviews conducted during the study. The number in
parenthesis on the X-axis represents the total number of interviews while the data from the Y-axis
represents the percentage of interviews.
0
10
20
30
40
50
60
70
80
90
100
% in
terv
iew
s
Animal species
Inceased Decreased Unsure No change
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4.1.3 Hunting
Respondents were asked whether Pygmy hippos/primate species found in their greater community
area were hunted. They answered either “yes”, “no” or “unsure”. Alarmingly, pygmy hippos received the
greatest number of “yeses” (58%) but chimpanzees and red colobus received the least amount (17%, 0%,
Figure E). It is important to point out that the killing of chimpanzees and pygmy hippos is illegal in Sierra
Leone, and that there has been an ongoing campaign by Tacugama Chimpanzee Sanctuary and the
Government of Sierra Leone to raise awareness about this law, so it is very possible that respondents did
not answer truthfully about hunting these species for fear of persecution, although many of the respondents
were Muslim, so there is also a religious taboo against eating primates. Interestingly, for some of those
respondents who stated they hunted, they also said they themselves did not eat bushmeat, but sold it for
profit.
26
Figure E. Communities and hunting.
The percentage of interviews where community members indicated they hunted each primate
species/pygmy hippo The X-axis indicates the species, and in parenthesis after the name is the total
number of interviews where this species was said to range (and therefore respondents we able to answer
this question).
Table 2. Summary results of interview data for priority species.
Species Presence (% of
communities
recorded these
species ranging in
their area)
Population trend Hunting (% of
communities
who said they
hunt these
species)
Black and White
Colobus
34% Declining 35%
Diana monkey 0% n/a n/a
Pygmy hippo 34% Declining 58%
Red Colobus 11% Declining 0%
Western
Chimpanzee
66% Declining 17%
0102030405060708090
100
% in
terv
iew
s
Species
27
4.2 Recces
4.2.1 Overall species presence
We walked 78.2 km along 49 recces ranging in length from 172.3m – 4198.1 m (average = 1533.6
m; SD = 1042 m). Considering only recces, and those mammal species that were the focus of this study,
we recorded signs from 13 species from three families. Further, we recorded an additional species, the
Patas monkey ad libitum (Table 3)
The most common sign observed of non-human animals were of Western chimpanzees, followed
by Red river hogs, and then “primates”. Often in the field it is difficult to attribute indirect sign of primate
presence (e.g. feeding remains) to a particular species and therefore, the majority of indirect signs of
primates were not categorized to the species level. Because our recces were in part biased to search for
locations thought to be inhabited by chimpanzees, the result of a very high encounter rate for chimpanzee
sign should be interpreted with caution. Recces for this study were primarily biased to search for signs of
priority species, therefore the variation in encounter rates among all species may have been affected by
this bias.
28
Table 3. A comparison of the results using three methods. Priority species are highlighted.
Camera traps Recces Interviews
Order Common name Scientific name Intl
status
#
independent
events
#
locations
Trap
success
Encount
er rate
# recces
encountered
on
% villages
respondents
replied ‘yes’
to presence
# villages that
replied ‘yes’
to presence
CARNIVORA Genet spp. Genetta sp. n/a 9 5 6.1 n/a n/a n/a n/a
Mongoose sp. n/a 1 1 0.68 n/a n/a n/a n/a
Otter sp. 0 0 0 0.05 2 n/a n/a
CETARTIOD
-ACTYLA
Bay duiker Cephalophus dorsalis NT 0 0 0 0.01 1 75% 33
Black duiker Cephalophus niger LC 0 0 0 0 0 82% 36
Bongo Tragelaphus
eurycerus
NT 0 0 0 0 0 45% 20
Bushbuck Tragelaphus scriptus LC 1 1 0.68 0.17 9 91% 40
Forest hog Hylochoerus
meinertzhageni
LC 0 0 0 0 0 48% 21
Maxwell’s
duiker
Philantomba
maxwellii
LC 1 1 0.68 0.18 8 93% 41
Pygmy hippo Choeropsis
liberiensis
EN 0 0 0 0.09 3 34% 15
Red river hog Potamochoerus
porcus
LC 0 0 0 0.59 21 95% 42
Royal antelope Neotragus pygmaeus LC 0 0 0 0 0 23% 10
Warthog Phacochoerus
africanus
LC 0 0 0 0 0 18% 8
Waterbuck Kobus ellipsiprymnus LC 0 0 0 0 0 30% 13
Water
chevrotain
Hyemoschus
aquaticus
LC 9 3 6.08 0 0 80% 35
Yellow-backed
duiker
Cephalophus
silvicultor
NT 0 0 0 0 0 52% 23
PHOLIDOTA Giant ground
pangolin
Smutsia gigantea VU 0 0 0 0 0 84% 37
White-bellied
pangolin
Phataginus tricuspis
VU 0 0 0 0 0 91% 40
29
CAMERA TRAPS RECCES INTERVIEWS
Order
Common name Scientific name Int’l
status
#
independent
events
#
locations
Trap
success
Encount
er rate
#recces
encountered
on
% villages
respondents
replied ‘yes’
to presence
# villages that
replied ‘yes’
to presence
PRIMATE Black and White
Colobus monkey
Colobus polykomos VU 0 0 0 1 34% 15
Campbell’s
monkey
Cecropithecus
campbelli
LC 0 0 0 0.06 4 48% 21
Green monkey Chlorocebus sabaeus LC 0 0 0 0.01 1 73% 32
Human* Homo sapien n/a 3 3 2.03 0.86 n/a n/a n/a
Olive baboon Papio anubis LC 0 0 0 0 0 34% 15
Patas monkey Erythrocebus patas LC 2 1 11.49 0.05 0* 89% 39
“Primate” n/a n/a n/a n/a 0.46 n/a n/a n/a
Red colobus Piliocolobus badius EN 0 0 0 0 0 11% 5
Sooty mangabey Cercocebus atys NT 0 0 0 0.01 1 73% 32
Spot-nosed
monkey
Cercopithecus
petaurista
LC 0 0 0 0.01 1 93% 41
Western
chimpanzee
Pan troglodytes verus CR 0 0 0 6.2 29 66% 29
RODENTIA African brush-
tailed porcupine
Atherurus africanus LC 9 4 6.1 n/a n/a
n/a
n/a
Fire-footed rope
squirrel
Funisciurus pyrropus LC 4 2 2.7 n/a n/a n/a n/a
Giant-pouched
rat
Cricetomys emini LC 5 3 3.4 n/a n/a n/a n/a
TULIDENTA-
TA
Aardvark Orycteropus afer LC n/a n/a n/a 0.04 1 n/a n/a
CR = Critically endangered; EN = Endangered; NT = Near threatened; VU = Vulnerable; LC = Least concern. n/a indicates species we not recorded on recces, or
asked about in community interviews, or did not appear on camera trap photographs.
30
4.2.2 Human disturbance
Besides chimpanzees, there were more signs of human disturbance (gun cartridge shells, mining
evidence, etc.) than any large mammal on the recce walks (encounter rate = 0.7 signs/km). Hunting was
the most common sign, followed by artisanal mining, and logging (Figure F, G, H). It is important to point
out that data on agriculture were only recorded on recces, and not outside of the recces, so any observation
of agriculture in this study were only those evidences found in the forest patches/areas we surveyed, and
were thus underestimated. Many areas within the DMU are dominated by slash and burn agriculture, and
therefore these data do not represent the area as a whole. In 2018, we will be collecting data along
systematically placed transects, and these data will give us information on human disturbance activities
across the DMU, rather than just those found on transects placed primarily in forest patches.
Figure F. The number of human disturbance activities in the study area.
Data are included from recces, ad libitum observations, and camera traps.
0
10
20
30
40
50
60
70
80
90
100
Agriculture Gold-mining Hunting Logging Settlement
% o
f si
gns
of
hu
man
dis
turb
ance
Human disturbance type
31
Figure G. The distribution of habitat disturbance types across the study site. Data were collected
only on recces; therefore the predominance of slash and burn agriculture across the landscape are not
represented by these data, rather the data displays human disturbance primarily along recces, which were
mainly in forested areas.
32
Figure H. Survey effort and human disturbance activities
Each grid cell is 1 km x 1 km and represents an area that was covered during the recces. Each colored grid
(see legend) represents the presence of a human disturbance activity(s) encountered while collecting data
on the recces. The absence of color in a grid represents an area that was surveyed, but evidence of human
disturbance was not recorded. Data were collected only on recces; therefore the predominance of slash
and burn agriculture across the landscape are not represented by these data, rather the data displays human
disturbance primarily along recces, which were mainly in forested areas.
33
4.3 Camera traps
We captured a minimum of 16 species of mammals and birds from six orders (Primates, Rodentia,
Carnivora, Canidae, Cetartiodactyla, and Musophagiformes). Sixteen is the minimum because there were
some species that we were unable to identify to the species level (only Genus). For the purposes of this
study, we are only interested in the results of Primates and Cetartiodactyla, but we present all results in
Table 3. See Annex for examples of mammals captured in the camera traps. None of the five priority
species were recorded with the camera traps.
Seven cameras were placed in Gallery forest, two in Woodland, and one in Hillslope. Of the ten
cameras deployed, one camera malfunctioned soon after installation and one camera captured no images
(but was functional). Animal images were captured in eight out of the ten cameras. The total trap nights
of effort was 148 (mean =16.6 days; SD = 1.9). There were a total of 212 photographs, constituting a total
of 75 independent events. Of the sixteen-identifiable species photographed, only four were large mammals
(i.e. Maxwell’s duiker, Bushbuck, Patas monkey, and Water Chevrotain). Four cameras (18 photos)
captured either hunters or domestic dogs. The camera that malfunctioned was placed in a Gallery forest
along the Seli River, inside the inundation area, in a location thought to contain Pygmy hippos.
4.4 Priority species
4.4.1 Western chimpanzees
4.4.1.1 Potential grouping patterns
Using recce walks and ad lib data, we confirmed chimpanzees still range in six of the nine areas
previously identified by past studies as areas chimpanzees range in (Nippon Koei 2007, Samba 2013,
Ganas & Garriga 2014, Garriga & Humle 2016, Garriga 2016, Figure C, Table 4). Of the three areas that
were unconfirmed, one area was surveyed, and two remain un-surveyed (see page 37 for further details).
34
Confirmed areas include the Bumbuna Conservation Area, Worowaia, Kamasapi, Yisaia, Kondembaia,
and Kamaron (Figure I). In addition to verifying their continued presence in these areas, we also increased
our understanding of where these chimpanzee groups range, expanding on knowledge from previous
surveys (Figure I).
We also identified five previously unknown areas where chimpanzees range (Table 4, Figures I,
J). The first new grouping is less than two kilometers from the inundation area boundary, near the village
of Gbogoroma, (“Gbogoroma group”). For the purposes of this study, we use the term “group” to identify
evidence of chimpanzees located very close together (evidence < 4 km apart from each other).
The second grouping is farther north, in forest patches located between Konkoma, Konkoba 2, and
Tonkoia (“Konkoba 2 group”). In this latter area, the majority of nest locations are relatively close
together, but there is also a group of nests approximately 4 kilometers to the north of these particular nest
locations (Figure I). We also collected dung from these northern nest groupings. Genetic analysis in this
study documented different individuals between these two sub-groups, but further collection and analysis
is needed to accurately determine if this is one or two separate communities. During the 2018 survey,
priority will be placed on collecting dung samples from both areas.
The third area is just east of the village of Temne Moria (“Temne Moria group”), approximately 4
km north of the eastern portion of the inundation area (Figure I). Preliminarily, based on both distance and
human activities in these areas, we can suggest that these three new “group” locations are possibly
different groups from what is currently known. However, without visual or genetic identification, this
cannot be completely verified.
35
The fourth grouping is approximately 2 km southeast of the farthest most eastern tip of the
inundation area (“Dukono group”, Figure I). This area is highly degraded with a few very small patches
of forest, surrounded by slash and burn agricultural activities (pers obs).
The final new group (“Benekoro group”), found near the village of Benekoro, south of the
inundation area may or may not be the same group of chimpanzees as those verified in Yisaia (Figure I).
As well, the Kamaron group may or not be part of the Yisaia group. Agricultural activities in these areas
are high, with relatively few forest patches. One possibility could be that there are multiple groups with
few members living in these different small forest patches. A second possibility is that these three distinct
observations are from one group, and this group travels very far among the forest patches in search of
food and nesting sites. We aim to focus efforts on dung collection in 2018 in these areas to aid in
determining the number of chimpanzee groups in this area.
36
Table 4. The different chimpanzee “groups” documented during this study.
For the purpose of this analysis, we defined “group” as a group of evidence from chimpanzees located <4 km from each other. One group of
points within the Konkoba 2 group are nearly 4 km apart from another group of locations. Here, we consider them the same group, but hope to
further investigate this group in 2018.
Chimp group Previously
known or new
group
Approximate
distance to the
Yiben Inundation
Area (km)
Collected
dung
samples?
Comments
Kondembaia
Previously known
<75 meters
No -In 2016, evidence recorded inside inundation area.
-In this study, nests recorded on either side of inundation area.
-Flooding is likely to fragment the suitable habitat available to
this group or restrict access to certain parts of their range
Gbogoroma
New
1.1
Yes Forest patches in this area also contain Black and White
Colobus
Yisaia
Previously known 1.4
Yes May or may not be part of the Kameron group and/or part of
the Benecoro group
Kamaron
Previously known 1.7
No May or may not be part of the Yisaia group (distance between
locations is 4 km away)
Dukono New 2.2 No
Temne Moria New 3.7 No
Benecoro New 4.1 No May or may not be part of the Yisaia group
Konkoba 2
New 13.7 Yes One nest group in the northern most section of these locations
may or may not be part of this group
Bumbuna
Conservation Area
Previously known n/a Yes
Worowaia Previously known n/a Yes
Kamasapi Previously known n/a Yes
37
Figure I. Recce survey effort and locations of the proposed chimpanzee groups.
Each grid cell is 1 km x 1 km and represents an area that was covered during the recces.
38
With the exception of evidence from the Kamaron and Dukono groups, all chimpanzee evidence
indicated (via fresh nests) that the chimpanzees were using these areas in June of 2017 (Figure K).
Research in 2018 will help understand the chimpanzees’ habitat use patterns, and whether certain areas
are used seasonally or year-round.
There were also areas that we either could not re-confirm chimpanzee presence, or that their
density was previously documented to be very low, and current survey efforts was dedicated elsewhere
(Figure L). First, although one chimpanzee was found to range in the inundation area in 2016 (a single
male chimpanzee, “Hut 44”, Garriga 2016) due to time limitations, the teams decided to concentrate
survey efforts elsewhere. Second, given that Garriga (2016) could not re-confirm evidence of chimpanzees
in the Kamandi area (documented by Ganas & Garriga 2014), we also did not conduct work in this area.
Although Brnic et al. (2010) and Ganas & Garriga (2014) recorded indirect evidence of chimpanzees in
here, during Garriga’s interviews with community members in the Kamandi area in 2016, it appears that
either a single chimpanzee or a very small group inhabits the area. Time permitting, we will conduct at
least one recce in this area to confirm presence/absence of chimpanzees. Third, we did not find any
evidence of chimpanzees in the Sandia-Fonema zone, where chimpanzees were previously documented
to range (Samba 2013, Ganas & Garriga 2014).
The reduced presence of chimpanzees in the inundation area is likely attributed to deforestation
and logging activities (Garriga & Humle 2016, pers obs). However, past studies have not found
chimpanzees to use this area extensively (Nippon Koei 2007, Samba 2013, Ganas & Garriga 2014, Garriga
& Humle 2016, Garriga 2016). This study documented the use of small forest patches by chimpanzees;
including areas very near the inundation area (Gbogoroma and Kondembaia groups). It is possible that the
vast majority of small forest patches that could support chimpanzees in the inundation area are now mostly
gone which could explain the lack of presence.
39
Figure J. Recce survey effort and locations of chimpanzee observations.
Each grid cell is 1 km x 1 km and represents areas that were covered during the recces. Each colored grid
(see legend) represents the encounter rate/km2 of chimpanzees in each of the grids. The absence of color
in a grid represents an area that was surveyed, but evidence of chimpanzees was not found.
40
Figure K. The locations of chimpanzees in June 2017.
Observations represent all fresh and recent sign, which include fresh and recent nests, dung, and feeding
remains, and any direct observations of chimpanzees. Each grid cell is 1 km x 1 km and represents areas
that were covered during the recces while points represent actual locations of nests/signs. The absence of
color in a grid represents an area that was surveyed, but evidence of chimpanzees was not found.
41
Figure L. A comparison of identified chimpanzee locations from 2014, 2016, and 2017.
Each grid cell is 1 km x 1 km and represents areas that were surveyed during the recces. Each colored grid (see legend) represents the
presence of chimpanzee sign or activities observed during the recces in particular years. The absence of color in a grid represents an
area that was surveyed, but evidence of chimpanzees was not found.
42
4.4.1.2 Genetic analysis
Of the 66 samples we collected for genetic analysis, we were able to successfully genotype 39,
resulting in the identification of 20 unique individuals from four groups (Bumbuna Conservation Area,
Kamasapi, Gbogoroma, and Konkoba 2; multiple samples could be from the same individual[s], Table 4).
For one group, “Konkoba 2”, we collected samples twice at two different locations separated by ~4km
(Figure I). Analysis demonstrated no overlap with individuals between these two sub-collections. This
tentatively suggests that these may be two separate groups; further collection in this area may help in
discerning if this group is one or two
Separate Chimpanzee groups that were defined by nest counts and groupings matched the results
from the genetic analysis. Although we identified more groups through nest counts than through genetic
analysis, this is because we were unable to collect samples from all groups. Considering those groups we
collected samples from, analysis identified between one and eight individuals per group, with a sex ratio
of 15 females to five males, although results varied by group (3:1 ratio; Table 5). Other field studies have
demonstrated an average sex ratio (female: male) of 1.4:1 (Hill et al. 2001), while this study documented
a 3:1 ratio. Although our results are too preliminary to confidently explain the differences between our
study and others, a skew towards females could be because males are the first individuals to be impacted
by hunting and inter-groups conflicts (the latter due to chimpanzees relocating to new areas out of
necessity, e.g. human disturbance). If this skew is indeed representative of the population of western
chimpanzees within the study area, this could demonstrate an uncertainty for their long-term survival here.
Interestingly, from the Bumbuna Conservation Area, we identified one male and seven females.
All samples were collected from the southern portion of the conservation area (samples were separated by
up to 1.8 km), because feedback from the local communities indicated that is where chimpanzees were.
Previous studies in this area found a maximum of nine individuals based on direct observation (four adults,
43
three juveniles, and two infants) and six individuals based on transects (confidence interval = 2 – 17;
Nippon Koei 2007; Samba 2013). Because dung is only collected from weaned individuals, this
preliminarily suggests that this community could be larger than previously thought. These results
underscore the usefulness of genetic analysis as a survey tool. It will be important to continue to collect
dung samples from this group during the 2018 dry season survey to allow a more precise estimate of group
composition and structure.
Although very preliminary, using mark-recapture model statistical analysis (CAPWIRE), we
calculated a population estimate of chimpanzees in the DMU. There are a minimum of 20 individuals in
the area, and we estimate a chimpanzee population of between 30 and 153 chimpanzees. As the sampling
area was not resampled multiple times and areas between sampling locations were not surveyed intensely,
this most probably represents an underestimate for the entire area. In order to obtain a population estimate
with a greater level of accuracy and precision, during the next field study in 2018, teams will focus on
collecting samples intensively from at least two groups of chimpanzees, where samples have already been
collected during this study.
44
Table 5. Chimpanzee genetic analysis
Groups where we were able to identify individuals and groups by genetic analysis are highlighted in gray.
Although samples were collected in Worowaia and Yisaia, due to issues with sample quality and
contamination, DNA was unable to be extracted from them.
Group Samples
collected?
# samples
collected
Total #
uniquely
identified
individuals
#
males
# females Comments
BCA Yes 26 8 1 7 Some samples here were mistakenly
stored improperly. This resulted in
the inability to extract DNA from all
samples.
Gbogoroma Yes 4 1 0 1
Kamasapi Yes 20 4 1 3 Although 20 samples were collected
here, two individuals were sampled
many times (unknowingly)
Konkoba 2 “a”
Yes 5 4 0 4 We are currently considering this
group and Konkoba 2 “b” the same
group based on locations of nests, but
these results underscore the need for
further sampling in this area.
Samples from Konkoba “a” and “b”
were 4.2 km apart
Konkoba 2 “b” Yes 4 3 3 0 We are currently considering this
group and Konkoba 2 “a” the same
group based on locations of nests, but
these results underscore the need for
further sampling in this area.
Samples from Konkoba “a” and “b”
were 4.2 km apart
Worowaia Yes 6 0 -- -- DNA was not able to be extracted
from these samples, possibly due to
age of sample (< 24 hrs. old)
Benecoro No n/a n/a n/a n/a
Dukono No n/a n/a n/a n/a
Kamaron No n/a n/a n/a n/a
Kondembaia No n/a n/a n/a n/a
Temne Moria No n/a n/a n/a n/a
Yisaia Yes 1 0 -- --
TOTAL
SAMPLES
20 5 15
45
4.4.1.3 Nesting site characteristics
In total (recces and ad-lib data), we counted 431 chimpanzee nests of four different age classes.
The greatest number of nest ages were classified as ‘old’, following by fresh, recent and very old (Figure
M). However, because nests do not stay in each stage for an equal amount of time, this doesn’t indicate
anything particularly significant about the chimpanzee population. Further, because chimpanzees
sometimes re-use nesting sites, the number of nests per site does not give an indication of the number of
chimpanzees in a group (Marchesi et al. 1995). Of these nests, Hillslope Forest contained most nests
(64.8%) followed by Gallery (21.4%), Woodland (32.8%) and Agriculture (0.9%; Figure N).
We identified a minimum of 19 tree species where chimpanzee made their nests, which was 30%
of the total number of trees (Figure N). The most common tree was Elaeis guineensis (Oil palm), followed
by Parinari excelsa, Dialium guinense, Melanie sp. and Cola lateritia. Cola lateritia was fruiting during
the study period and evidence of both chimpanzee and monkey feeding remains of this species were
documented. Botanical skills varied among teams and therefore the unidentified species of trees the
chimpanzees nested in may not be mutually exclusive from those that were identified. Further, the Oil
palm tree is one of the most easily recognized tree species, and all team members could identify it,
therefore it is possible that it is overrepresented in these results. Previous research in various locations in
West Africa have also documented these tree species as both important sources of food (fruit and nuts) as
well as nesting sites (Anderson et al. 1983; Brnic et al. 2010; Carvalho et al. 2014; Harding 1984; Humle
& Matsuzawa 2004; Hockings & Sousa 2013; Normand et al. 2009; Sousa et al. 2011; Yamakoshi &
Sugiyama 1995). Based on this information, we can preliminarily suggest that these species could also be
considered important for chimpanzees in our study area, and should be noted for future conservation and
rehabilitation plans in the area.
46
Figure M. The number of chimpanzee nests categorized by age (following Tutin & Fernandez 1984).
Figure N. The percentage of habitat types each chimpanzee nest was located in.
Habitat classification following Collins & Mitchard (2017). See Appendix 2 for habitat type descriptions.
0
50
100
150
200
250
Fresh Recent Old Very old
Nu
mb
ero
f n
ests
Nest age
Agriculture Gallery Hillslope Woodland
47
Figure O. The frequency of tree species used for nesting by chimpanzees.
Not all species of trees were able to be identified (70.3% remained unidentified)
4.4.1.4 Chimpanzees’ use of the inundation area
Our current understanding of chimpanzee habitat use in the inundation area is that at least one
group uses this area (Kondembaia group, Garriga 2016), and four other groups have been documented to
range in close proximity (< 2 km, this study). Considering the Kondembaia group, not only have studies
documented chimpanzee sign in the inundation area, the current study documented nests on either side of
it, suggesting that this area of the inundation zone is somewhat important. Systematic transects are planned
for this area to better understand the degree of importance the inundation area has to this group, as well
as those chimpanzee groups that we have documented to range in close proximity.
Planned research in 2018 will systematically quantify larger areas using transects to not only
estimate population abundance, but also quantify habitat use in more detail. One interesting question is
0
5
10
15
20
25
30
35
Nu
mb
er o
f o
ccu
ran
ces
Tree species
48
how chimpanzees move among these forest patches. Many of the areas in between these forest patches are
farms, and/or areas populated by people.
Figure P. Locations of Western Chimpanzee evidence.
49
4.4.2 Pygmy hippos
Indirect signs of pygmy hippos were found in five different locations (Figure Q, T). (1) The first
is a single sign (trail) along the Seli river, inside the Yiben inundation area. (2) The second is a set of signs
also along the Seli River, separated by a minimum of ~500 meters [footprints]. (3) The third, fourth and
fifth signs are along the Mameli river, relatively near the villages of Kurekurena and Temne Moria [dung
and footprints]. Very little is known on the ranging patterns/habitat use of pygmy hippos. One study in
the Ivory Coast found that females have overlapping home ranges, and were 40 -60 hectares in size (Roth
et al. 2004). Therefore, it is possible that the two observations documented on the Seli River are from the
same individual, but these signs are far enough apart that they could also be considered to be from different
individuals. The three locations on the Mameli are likely to be different individuals. Previous research
described pygmy hippos as ranging close to Yiben, inside the inundation zone, along the Seli river (Nippon
Koei 2007, Samba 2013). Due to logistical reasons, we were unable to reach this area to confirm whether
pygmy hippos still ranged here. We plan to survey this area during the dry season in 2018.
The majority of pygmy hippo signs were located in Gallery forests (87.5%) followed by
Agriculture (12.5%). Pygmy hippos have very specific habitat requirements and are typically tied to rivers
(Hillers et al. 2017). Pygmy hippos are not necessarily found exclusively in rivers near/in forests, and a
recent study in southern Sierra Leone found that the majority of pygmy hippo sign was located in fallow
land or “farmbush” (close to rivers, Hillers et al. 2017). The closest confirmed population of pygmy hippos
resides in nearby Loma Mountains National Park, with the next population much farther south (~200 km)
in the Gola Forest National Park environs (Conway et al. 2014; Hillers et al. 2007, Kortenhoven 2009).
50
Figure Q. Locations of Pygmy Hippo evidence.
51
4.4.3 Black and white colobus
This study is the first since 1996 to observe Black and White Colobus. We observed two
individuals in a small forest patch near the village of Gbogoroma (Figure R). This species has been
difficult to locate, given their likely low density in the area and shy nature. Previous studies over the last
ten years failed to observe any signs of Black and White Colobus, so our research can be considered a
success, and an indication that this species still ranges in this area. We located this species in part because
our team specifically searched for it with the assistance of a local farmer. Black and White Colobus
monkeys are difficult to document with traditional transects/recces and this may partially explain why
previous research did not document this species. The western black and white colobus has a specialized
diet preferring unripe tree fruit seeds and leaves, and whose population density can be predicted by a high
protein to fiber ratio of mature leaves (DaSilva 1992; Chapman et al. 2002). Because of their ecological
needs, it is likely that there a few remaining habitats in the DMU that can support this species. Therefore,
forests where black and white colobus are found should be prioritized for protection. Planned further
targeted surveys will be conducted in this area and other potential black and white colobus ranges within
the DMU in 2018, which will give us a better understanding of their range and habitat use in the overall
study area and highlight which areas need preservation.
52
Figure R. Location of Black and White Colobus evidence.
53
4.4.4 Red colobus
We did not observe any sign of Red Colobus (only five villages indicated this species ranged in
the area). All previous studies in this area have not observed any signs of Red Colobus presence. It is very
likely that if Red Colobus still range within the DMU, they do so at a very low density. Further targeted
surveys in the dry season for 2018 may be able to provide stronger evidence for their survival, or lack
thereof, in the DMU.
Figure S. Locations of Red Colobus surveys. Grid cells are used to ensure that particular areas are
equally covered, and as well, to determine which areas still need to be investigated for further surveys.
54
4.4.5 Diana monkey
We did not document the presence of Diana Monkeys either on recces or camera traps. The
presence of Diana Monkeys was also not confirmed in previous studies (Nippon Koei 2007, Samba 2013,
Ganas & Garriga 2014, Garriga & Humle 2016, Garriga 2016). No communities indicated Diana Monkeys
range in the area. The DMU is on the edge of the Diana Monkeys known range (Oates et al. 2016), and it
is possible that either Diana monkeys have never ranged here, or it has been a long time since they have
been present.
55
Figure T. Recce survey effort and three priority species locations.
Each grid cell is 1 km x 1 km and represents areas that were covered during the recces. Each color
represents the different priority species encountered during the recces. The absence of color in a grid
represents an area that was surveyed, but evidence of priority species was not found.
56
4.5 Comparisons of 2017 survey data with previous studies
Comparing our results with surveys undertaken for EIAs in 2014 and 2016 show some interesting
differences, which likely can be attributed to the survey designs of each study. Previous EIAs used
traditional recces which followed a path of least resistance not varying by more than 40°, while our
research biased recces in our search for the five priority species, including visiting areas known to be
inhabited by western chimpanzees to collect dung. Because of the bias, the majority of recces in this study
were located in the two habitats where chimpanzees and pygmy hippos were primarily found (Hillslope
and Gallery forests). As a result, the encounter rate for chimpanzees in this study is dramatically higher
(6.2/km vs. <1/km for all others since 2014, Table 6) than previous research. Likewise, differences in
recces could account for a much lower encounter rate of generalist ungulates like the Bushbuck, that can
adapt to a variety of habitat types. Interestingly, this study has been the first to document the presence of
black and white colobus, and the first since 2013 to document pygmy hippos.
57
Table 6. A comparison of encounter rates for four studies between 2014 – 2017.
Previous studies collected data on small mammals, but because they were not the focus of this study, we
do not present those data here. Priority species are highlighted.
Order Common name Scientific
name
Int’l
statu
s
ER-
this
study
ER –
July
2016
ER –
April
2016
ER –
May
2014
CARNIVORA Otter sp. NT1 0.05 0 0 0
CETARTIODACTYLA African buffalo Syncerus
caffer
LC 0.15 0.33 0.03 0.08
Bay duiker Cephalophus
dorsalis
NT 0.01 0 0.11 0.03
Black duiker Cephalophus
niger
LC 0 0 0 0.03
Bongo Tragolaphus
eurycerus
NT 0 0 0 0.03
Bushbuck Tragelaphus
scriptus
LC 0.17 0.51 1.05 2.79
Maxwell’s
duiker
Philantomba
maxwellii
LC 0.18 0.37 1.14 1.48
Pygmy
hippopotamus
Choeropsis
liberiensis
E 0.09 0 0 0
Red river hog Potamochoeru
s porcus
LC 0.59 0.51 0.65 0.4
Red-flanked
duiker
Cephalophus
rufilatus
LC 0 0 0.03 0
Warthog Phacochoerus
africanus
LC 0 0 0.03 0.46
Waterbuck Kobus
ellipsiprymnus
LC 0 0 0 0.03
Yellow-backed
duiker
Cephalophus
silvicultor
NT 0 0.09 0.11 0.4
PHOLIDOTA Pangolin sp. V1 0 0 0.03 0.03
PRIMATE Black and White
Colobus
Colobus
polykomos
V 0.01 0 0 0
Campbell’s
monkey
Cercopithecus
campbelli
LC
0.06 0.12 0.06 0.03
58
1These animals were not able to be identified to species, and likewise, for the species that range in Sierra Leone, Genus differs,
so only the common name is provided. 2Although we did not document Patas monkeys on the recces, we observed them in the
field (ad lib) and as well recorded 2 independent events of them on a camera trap. 3Animals classified as ‘monkey’ from past
studies are classified as ‘primate’ here. The broad classification is due to the difficulties of identifying indirect primate signs
to the species level.
4.6 Human activities and priority species
Based on our results, it appears that the remaining pygmy hippo population in the study area is
under severe threat. Pygmy hippos, although only verified in 12 villages (27.2%) as occurring in the area,
received the greatest percentage of affirmative responses as to whether they are hunted (Figure E). We
also found that the number one human disturbance activity along the recces was artisanal gold mining
(Figure G). Garriga (2016) also documented mining in other locations along the Seli river in 2016. Mining
has been suggested as a major threat to pygmy hippo populations in their range (Collen et al., 2011;
Ransom et al. 2015) and can be considered the same here. Some of the local field assistants that we worked
with during the pygmy hippo searches noted that gold mining had driven away pygmy hippos from areas
they were previously found in. Avoiding any damage to the remaining habitats where pygmy hippos are
currently found in must be considered a major conservation priority in this area.
Green monkey Chlorocebus
sabaeus
LC 0.01 0.01 0 0
Lesser spot-
nosed monkey
Cercopithecus
petaurista
LC 0.01
0 0.06 0.03
Patas Monkey2 Erythrocebus
patas
LC 0* 0.01 0 0
Primate3 n/a 0.46 0.37 0.63 0.88
Sooty mangabey Cercocebus
atys
NT 0.01 0.04 0 0
Western
chimpanzee
Pan
troglodytes
verus
CE 6.2 0.10 0.91 0.54
TUBULIDENTATA Aardvark Orycteropus
afer
LC 0.04 0.04 0.03 0.03
59
4.6.1 Hunting
Hunting appears to be one of the greatest threats to biodiversity in the DMU, a similar threat across
sub-Saharan Africa (Brashares et al. 2004; Laurance et al. 2006; Walsh, et al. 2003). In our study, between
17 and 58% of respondents indicated that they hunt either primates or pygmy hippos. It is also illegal to
kill chimpanzees and pygmy hippos in Sierra Leone, so the amount of people hunting these species is also
probably an underestimation. To be successful, any conservation efforts in the future in this area must
address hunting.
4.6.2 Habitat destruction
Although not quantified during our study, habitat destruction is also a major threat to priority
species in this area. The majority of evidence of priority species were located in very small forest patches
surrounded by slash and burn agricultural activities. There are currently no laws or restrictions that prohibit
communities from cutting down these remaining forest patches, and in fact, we observed logging and slash
and burn agricultural activities of forests patches during our study. Primates can move between forest
patches for survival, but they may not choose to do so if hunting is occurring or if there is no possibility
due to high human population. For priority species survival in this area, protection of the few remaining
forest patches must be a major priority. It is important to note that human agricultural activities currently
dominant inside of the Bumbuna Conservation Area, with only a few very small remaining patches of
forest. Additionally, evidence of hunting was also recorded here. Given its status as a protected area, and
that a group of Critically Endangered Western Chimpanzees resides here, these observations were
alarming.
60
4.6.3 Crop-raiding
One situation that may create conflict and reduce tolerance between species such as chimpanzees
and local people is crop-raiding. During our interviews, 45% of villages (13) that reported chimpanzee
presence in their area also claimed that chimpanzees raided their crops. However, most community
members also stated that chimpanzees were not the worst culprits of crop-raiding and instead underscored
the damages inflicted on their crops by species such as Patas monkeys and Green monkeys. For future
successful conservation effort in the area, it will be important to understand the link between an animal’s
food availability in their habitat, crop availability, and distance of farms to forests (Hill 1997, Naughton-
Treves et al. 1998, Warren et al. 2007).
4.7 Project impact on priority species
The observation of up to eight chimpanzee groups inside the DMU (not including the three groups
near Bumbuna) indicates that more chimpanzee groups will be impacted either indirectly or directly by
project activities than previously thought. With the flooding of the inundation area, one group,
“Kondembaia group” will lose part of its territory (further studies in 2018 will aim to quantify how much).
The remaining groups will be indirectly impacted by competition for resources with humans from
resettlement of communities from inside the inundation area to other areas within the DMU. There is also
the potential that the loss of habitat from project activities and/or human resettlement will push
chimpanzee groups towards each other resulting in conflict (potentially lethal) between groups. Given that
chimpanzees are already under intense pressure in the area from habitat loss and hunting, it is imperative
that these remaining habitats are protected (primarily Hillslope and Gallery forests). Given the added
importance of forests for soil and water conservation, preventing landslides, and climate regulation, it is
also in the best interests of local people to work towards preserving these areas.
61
The observation of pygmy hippo sign along the Seli River indicates that some or all of their habitats
in these areas will be lost due to project activities (primarily by flooding the Yiben inundation area).
Although the habitat requirements of pygmy hippos include access to water (Hillers et al. 2017), flooding
does not necessarily mean that their habitat availability will increase. Although our knowledge of pygmy
hippos is limited, we know that in Southern Sierra Leone, over half of pygmy hippo evidence was
documented in farmbush (farmed areas that are regenerating), where herbaceous vegetation, the primary
item in their diets grows (Hillers et al. 2017). By flooding the inundation area, although water availability
will increase, it will probably destroy large areas of food availability for pygmy hippos. This study also
documented pygmy hippo signs along the Mameli river, outside of the inundation area (Figure Q). If
mitigation cannot occur to preserve areas on the Seli river for pygmy hippos, we recommend that
conservation activities, including sensitization of the local population, in areas within the DMU, such as
the Mameli river, take place.
The forest patch near Gbogoroma where Black and White Colobus were observed should be also
be prioritized for protection.
4.8 Mitigation
Based on this study’s findings, we suggest the following mitigation activities:
Avoidance
• Avoid the relocation of villages from inside the inundation to areas near where priority species
are found to avoid placing additional pressure on these forest patches.
• We suggest that communities are not relocated within 7 km of forest patches inhabited by
priority species. This is justified because we observed that community members are willing to
walk very long distances per day to farm (which is done primarily by burning forest). In this
62
way, the priority species will be buffered to some degree from potential habitat loss. Social
survey teams should discuss this with communities for input
Minimization
• Led by conservation collaborators, conduct environmental/conservation sensitization campaigns,
focusing in communities near the areas where priority species have been found (Figure T).
• Sensitisation should include information on the illegality of killing chimpanzees and pygmy
hippos, and the importance of Gallery and Hillslope forests not just for priority species, but for
water and soil conservation for local communities.
Reforestation
Consider reforestation activities to connect forest patches as some are relatively close
together.
Additional conservation measures
• Establish collaborations with local and/or international conservation partners to direct
conservation programmes to monitor priority species and illegal activities within the DMU; these
activities should be developed in collaboration with local communities in a bottom up approach.
63
Figure U. Priority species occurrence and human disturbance.
Each grid cell (1 km x 1 km) represents an area that was surveyed. There are individual points to represent
each priority species observation, and if any human disturbance activities occurred in that surveyed cell,
it was colored red.
64
5 SUMMARY / CONCLUSIONS
5.1 Summarized field results
• We conducted 64 interviews in 44 villages, with communities identifying 24 species of large
mammals ranging near their villages.
• We identified the presence of 16 species of large mammals via recces, camera traps, and ad libitum
data, including the priority species Western Chimpanzees, Pygmy Hippos, and Black and White
Colobus.
• We documented 13 species of mammals (including small mammals) on the camera traps (not
including domestic dogs and hunters). None of the five priority species were captured by the
cameras.
5.2 Western Chimpanzees
• Western chimpanzee’s nests were the most common sign documented on the recces, but recces
were biased to search for chimpanzees.
• We confirmed the presence of six of the previously nine groups/areas chimpanzees documented in
past studies (Bumbuna Conservation Area, Kamasapi, Worowaia, Yisaia, Kondembaia, Kamaron)
• We recorded the presence of chimpanzees in five new areas (Gbogoroma, Konkoba 2, Temne
Moria, Kukono, and Benekoro). It could be possible that there are three to five chimpanzee groups
from these locations. Further research, including continued genetic analysis, will aid in discerning
among the groups.
• Chimpanzee evidence (primarily nests) was primarily found in two habitat types: Hillslope
(64.8%) and Gallery (21.4%) forests. These habitats should be prioritised for protection.
65
• Chimpanzees were not recorded inside the inundation area in this study, but four groups were
recorded ranging <1.7 km away from the boundary.
• The “Kondembaia” Chimpanzee group uses part of the inundation area in its home range and will
be directly impacted by habitat loss as a result of planned flooding. The remaining Chimpanzee
groups may be indirectly impacted by competition for resources with people, especially if
communities that are relocated from the inundation are placed close to where the Chimpanzees are
ranging.
• Tree species that can be considered important to western chimpanzees in the study area, based on
the location of nests include Elaeis guineensis (Oil palm), Parinari excelsa, Dialium guineense,
Melanie sp., and Cola lateritia.
• Of the 66 samples we collected for genetic analysis, we were able to successfully genotype 39,
resulting in the identification of 20 unique individuals from four groups.
• The genetic analysis documented 15 females and 5 males, indicated a 3:1 sex ratio. Although the
genetic identification of more individuals in this area is important to determine if this sex ratio is
true throughout the population, these results may indicate that males have been negatively
impacted by hunting and/or competition with other groups as resources in this area are limited.
• Mitigation efforts should include biomonitoring of Chimpanzees populations along with
simultaneous monitoring of human disturbance activities, as well as sensitization campaigns.
5.3 Pygmy Hippos
• We observed pygmy hippo signs in five different location. Two locations were along the Seli river,
in the inundation zone. The remaining three were located on the Mameli River relatively near the
villages of Kurekunema and Temne Moria.
66
• Despite deploying eight camera traps in areas where pygmy hippos were thought to range, cameras
failed to capture any pygmy hippos evidence, however they are notoriously difficult to capture on
camera traps.
• Pygmy hippos along the Seli river will be directly impacted by project activities (i.e. flooding) by
the loss of herbaceous vegetation, their primary food source.
• Mitigation should include addressing the artisanal gold mining that is occurring throughout the
area, as this activity negatively effects pygmy hippos and adding conservation activities around
the Mameli rivers, where pygmy hippos occur outside the inundation, but inside the DMU.
5.4 Black and White Colobus
• We documented the presence (direct sighting) of two Black and white colobus monkeys in a small
forest patch relatively near the village of Gbogoroma, approximately 3 km north of the inundation
area.
• This is the first survey in Bumbuna to document the presence of this species.
• This forest patch should be prioritised for protection.
5.5 Red Colobus and Diana Monkeys
• Although five villages indicated that red colobus still ranged in the area (at low numbers), we were
unable to verify its presence in the field.
• No villages indicated Diana Monkeys ranged in the area, and we also were unable to document its
presence. Past studies have been unable to observe their signs. This may indicate that this species
has been locally extirpated for some time.
5.6 Ungulates
• We recorded six of the possible 14 species though to range in the area (excluding pygmy hippo)
67
• The most common ungulate sign recorded was the Red River hog
• We did not record the Bongo (threatened species) by recces/camera traps, although 14
communities indicated they ranged around their communities.
5.7 Human disturbance
• The landscape throughout the DMU is dominated by villages and vast amounts of slash and burn
agriculture
• Human disturbance is relatively high in the area. Its signs were the second most recorded
observation on recces. Camera traps also recorded signs of hunting through pictures of a hunter
with a gun, and in another location, a domestic dog, which may have been a hunting dog.
• The most common human disturbance sign recorded was hunting, following by gold mining, and
hunting.
• Considering Primate species and Pygmy Hippos, up to 58% of respondents in community
interviews indicated that they hunt these species. Alarmingly, pygmy hippos received the greatest
percentage (58%) of positive responses to hunting. Chimpanzees response was relatively low
(17%) however, killing chimpanzees and pygmy hippos is illegal in Sierra Leone, so there is a
strong chance that not all respondents answered truthfully.
• Ameliorating human disturbance activities must be a part of successful conservation activities in
the area.
68
6 RECOMMENDATION FOR DRY SEASON 2018 SURVEY
We propose the following actions for the field surveys in 2018:
1. Conduct systematic transect sampling in targeted areas within the Terrestrial DMU to estimate
chimpanzee abundance and aid in the creation of a habitat suitability map for this species for the entire
area. Transects will be placed in areas confirmed to contain chimpanzees. We propose placing transects
in either one of the following areas:
a) Gbogoroma area. This area contains a relatively high number of signs (74) in four distinct areas. These
forest patches also contain Black and white colobus monkeys.
b) Konkoba 2 area. We recorded a relatively high number of chimpanzee sign (176) in this area.
c) Benekoro/Yisaia/Kamaron/Kormontor area. Ecologically, this area is different from Gbogoroma and
Konkoba 2 areas. This area is highly degraded and forests patches appears to be small and far apart.
Collecting data in this area will not only contribute to the population size estimate, but will help us better
understand chimpanzee habitat use in this area.
d) East of Kondembaia. Transects would cover where the Kondembaia groups ranges, and portions of the
inundation area which have not been previously surveyed. Given the groups proximity to the inundation
area (locations <75 m, and in 2016, evidence documented within it), surveying this portion is important.
2. Conduct additional recces in areas thought to contain chimpanzees, but not covered under
planned transect surveys in 2018. Based on information discovered towards the end of the current
study’s fieldwork, we suggest collecting data on recces in areas near Temne Moria, and area(s) near
Kamandi where studies in 2010 and 2014 confirmed chimpanzees, but where Garriga (2016) could not re-
confirm their presence. A second investigation here would more strongly confirm chimpanzees no longer
69
ranged in this area. A third area is locations northeast of Yisaia, where this group may also range, but has
yet to be investigated.
3. Continue to collect chimpanzee dung for genetic analysis, placing priority in the Bumbuna
Conservation Area and areas where we do not fully understand the number of chimpanzee groups.
These areas include the Benecoro-Yisaia-Kamaron range and Konkoba 2, the latter where genetic analysis
showed no overlap in uniquely identified individuals between the two collection areas. However, we will
try and collect dung samples from as many individuals and groups as possible.
4. Additional recces to survey for pygmy hippos in targeted areas
Based on our current findings, these targeted areas include:
a) The area just north of Yiben on the Northern side of the Seli River. Due to logistical reasons, we were
unable to reach this area during this field season. During his 2013 study, Samba detected pygmy hippos
in this area (‘Sandia-Fonema”) and therefore we plan to re-visit these same areas to determine whether
pygmy hippos continue to range here.
b) Areas along the Mameli river, moving both northward and southward from where our study
documented hippos. Of particular importance will be the area south of the southernmost location where
this study documented this species on this river (Figure Q). This is approximately 1.1 km away from the
boundary of the inundation area, and the Mameli continues to flow south through it. This is also the same
area that the Kondembaia chimpanzee group has been documented to range in.
c) Areas where the Mameli river meets the Seli river, in the inundation area. While conducting a recce
near this area, local people told us that pygmy hippos use this area seasonally. While we did not find
evidence of hippos during this wet season, re-surveying this area in the dry season will be important.
70
d) The Seli river, moving west from where we documented pygmy hippos, within the inundation area
(Figure Q).
5. Additional recces to survey for Black and White Colobus in targeted areas. These represent areas
we did not reach during this study, due to time limitations. They include:
a) The southern portion of inundation area, moving west along the Seli River (Figure R).
b) A forest patch relatively near the village of Lengekoro (Figure R).
6. Additional recces to survey for Red Colobus in targeted areas.
a) Forest patch southeast of the village of Makakura (Figure S).
b) Riverine forest south of the village of Bendukura (Figure S).
c) Forest patches near the villages of Kasine and Bendukoro (Figure S).
7. Additional village interviews along the road from Kabala southeast to Kamadugu Sokurela to
document any additional locations for priority species, in particular Western chimpanzees and pygmy
hippos. This area was not covered during the present survey and based on local reports, the possibility
remains these species range here.
71
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8 APPENDICES
8.1 Appendix 1. Supplementary maps
(A) A map detailing the 1 km x 1 km cells used to display areas of survey, and the actual recces walked.
Grid cells are used to ensure that particular areas are equally covered, and as well, to determine which
areas still need to be investigated for further surveys.
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(B) A map documenting the precise locations of direct and indirect evidence of priority species.
78
(C ) The locations of other mammal species documented during the survey.
Each grid cell is 1 km x 1 km and represents areas that were covered during the recces. Each colored point
(see legend for specific species) corresponds to the precise location on the recces the observation was
documented. Grid cells are used to ensure that particular areas are equally covered, and as well, to
determine which areas still need to be investigated for further surveys.
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8.2 Appendix 2. Habitat type definitions
Habitat type Definition
Gallery >15 m trees; >60% canopy cover; <150 m
water
Hill Slope Forest >15 m trees; >60% canopy cover
Woodland Mixed tree/grass, occasionally or frequently
burned
Seasonally wet grassland Up to 1 m high grass; inundated some of the
year; over bedrock in depressions
Freshwater swamp Swamps in river/stream valleys on
sand/muddy soils. Sedges, grasses and herbs
River channel community Herbs/woody species on/around rocks in river
beds or river banks
Inselbergs Granite outcrops with tussock sedge grass
Agriculture Crops actively grown. If abandoned, should be
classified as Woodland
Exposed substrate Sand/Rock/Clay
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8.3 Appendix 3. A selection of photographs of large mammals captured on the camera traps.
(A) A male bushbuck
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(B) A water chevrotain
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(C) A female and offspring from a troop of Patas monkeys
(D) Sub-adult and juvenile Patas monkeys
83
(E) A male Patas monkey
(F) Maxwell’s duiker
+
84
(G) A domestic dog
(H) A hunter with rifle
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8.4 Appendix 4. Photographs of field observations
a) Community interviews
b) Community interviews
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c) Chimpanzee nest
d) Chimpanzee nest
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e) Chimpanzee dung with seeds
f) Fresh chimpanzee dung for collection
88
g) Collecting chimpanzee dung
h) Fruits of Cola lateritia which can be considered important for chimpanzees in the study area
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i) Pygmy hippo footprint
j) Pygmy hippo dung
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k) Buffalo footprint
l) Maxwell’s duiker dung
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m) Active gold mining
n) Old gold mining camp
92
o) Gold mining pit
p) Slash and burn agriculture
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q) Hunting
r) Snare
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s) Gun shell cartridge
t) Logging boards
