mohamed kamara biological sciences njala university njala campus
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Mohamed KamaraBiological Sciences
Njala UniversityNjala Campus
Specific objectives: Species richness Species composition and relative
abundance Identification of threatened species
and monitoring Bat plant interaction and bush meat
hunting
Study area and study sitesThe Gola Forest is located in the southeast
of the Eastern province of Sierra Leone. The area extends along the international border where is nearly contiguous with the Gola National Forest in Liberia. Gola East (205Km2) and Gola West (67Km2) constitute one continuous block, which is interrupted by a dirt road. Gola north represents the largest section with 417Km2 and Extension ІІ (61 Km2) is situated North East of Gola North and has been recently added to the reserve.
Nocturnal Highly mobile Sole mammals able to fly Second diverse mammal order after
rodents Often most diverse mammal order in
tropical species assemblages
Megachiroptera (Fruit bats)
Fam: Pteropodidae
Microchiroptera (Insect bats)
Fam: occurring in Africa rhinolophidae hipposideridae nycteridae vespertilionidae miniopteridae molossidae megadermatidae emballonuridae rhinopomatidae
Visual orientationPollinators and seed dispersers of a broad
variety of forest tree and liana species, as well as economically important tree species.
Pollination: Ceiba petandra, Kegelia africana, Parkia
bicolor, Mucuna flagelllipes, Maranthes glabra, Pentadesma butyraceae
Seed dispersal: Parinaria excelsa, Uapaca spp.
Anthocleista spp. Cola gigantae, Ficus spp., Nauclea pobeguini.
Orientation with echolocation system
Mainly insectivorous diet, maintenance of food chains
High energy demands (high costs of flight)
High food intake in relation to body mass
Habitat indicatorHigh level of diversification, species
specific habitat requirements.
Mist-nets Canopy nets
Harp trap
Crossing of assumed fly-ways;― treefall gaps and other forest
openings― rivers and streams― forest paths
Day-roosts: ― hollow trees― Caves, cavities and crevices
Body mass body measurements: forearm, if
applicable body length, tail, ear, hint foot, tibia.
Age class Sex and reproductive state If applicable, echolocation recording DNA samples Faeces Parasite Blood samples Throat swabs
Primary sources ― data analysisCaptured bats were individually held in
cloth bags until been processed. We took body mass (in g) and forearm length (in mm) of all species that we subsequently released. Standard measurements (head and body, tail, ear, hind foot, tibia) were obtained from all collected individuals. We determine sex, age class and reproductive state.
Secondary sourceField guides and/or appendix on bat
submitted by other researchers.
Hypsignathus monstrosus (Pteropodidae)
Largest fruit bat of Africa Typical forest fruit bat species Male perform characteristic mating
calls Strong sexual dimorphism
Smallest fruit bats of Africa Typical forest fruit bat species Only obligate nectarivorous fruit bat
of Africa Carnivore Day-roosts in hollow trees Occupies small home range
Typical forest bat species Echolocation calls with nose Carnivore Day-roosts in hollow trees and other
vegetation structures
Typical forest bat species Echolocation calls with nose Perform perch hunting Day-roosts in hollow trees Occupies small home ranges
Very small and patchy distribution range Record during this survey constitutes the first
for Sierra Leone, and overall the first of the species after 20 years
Day-roosts in cavities Likely to require particular hilly forest habitat
One of the smallest fruit bat species (3-5g)
Echolocation calls with mouth Day-roosts in foliage Relative energetic costs for flight are
particularly high and require a proportional high food intake to maintain energy balance
We recorded 30 bat species in Gola Forest Reserve while missing four additional ones that had been previously recorded there (Eidolon helvum, Neoromicia nana, Mimetillus moloeyi, Mops spurrelli). Both the currently documented species richness (34-39) and estimated richness (45-47) is very high compared to other forest sites in tropical Africa that have been sampled for a limited time.
The best studied forest site in Africa is Taï National Park Ivory Coast, where 40 species have been recorded within an area of 47 Km2 over the coast of six years and base on >1500 captured individuals.
The composition of the bat assemblage reflects the habitat structure of Gola Forest Reserve: most of the species are strictly or predominantly associated with forest habitats (79.4%), while only few species occur in both forest and savanna habitat (11.8%) or predominantly in savannas (8.8%).
On the level of relative abundance , forest species were even more dominant as they comprised 90.6% of all captured individuals where as species typical found in savannas contributed only 2.2% to all individuals, and species showing no clear habitat association adding 7.2% to total pool of captures.
Vulnerable Rhinolophus hillorum Hipposideros marisaeTwo species of lower conservation concern:
Near threatened Neoromicia brunnea
Data deficient Kerivoula cuprosaMapping out cave locations and estimating bat
colonies would ideally lead to a monitoring program of bat caves, which constitute the necessary basis to evaluate the long term persistence of threatened species such as Hipposideros marisae and Rhinolophus hillorum within the protected area.
A large number of tropical plants depend on pollination and/or seed dispersal by fruit bats for their regeneration, including traditionally as well as commercially valuable plant species.\
Seed dispersal: Parinari excelsa, Uapaca spp., Sacoglottis
gabonensis, Anthocleista spp., Neuclea spp., Ficus spp., and Musanga ceropionides.
Pollination:Maranthes spp., Pentadesma butyracea and Parkia
bicolorExploitation of fruit bats within the boundaries of
the Gola Forest Reserve appears to be very limited
Previous result― 6 bat species in 3 families
Results this survey so far: ― 12 study sites: 10 in Gola Forest
Reserve and 2 study sites adjacent to the reserve.
― 230 individuals in 30 species and 6 families including 9 first country records.
The Gola Forest harbours a very diverse bat fauna, including species listed on the IUCN Red List of threatened species with highly specific habitat requirement
The Gola Forest provides many bat species with suitable habitat features, particularly day-roosts, which area obligate for these species to persist in a certain area.
Upgrading the protection status of the Gola forest to a national park will help to irrevocably exclude large scale logging or mining operations from the area, which still poses a lingering threat to the reserve.
Management programs should strive balancing the needs of local communities and their traditional use of forest products with a landscape approach that maximizes the functional size of the conservation area.