FACULTY OF AGRICULTURE

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    Population pattern and phenological behaviours for selected medicinal plants in Nigeria; implications for ex-situ conservation
    (2013) Oni, P.I.; Jimoh, S.O.; Adebisi, L.A.
    Recent developments indicated increasing gene-pool depletion for most medicinal plants in Nigeria despite their pharmaceuticals and therapeutic potentials. Initial socio-economic study involving three countries (Nigeria, Ghana and Republic of Benin) identified ten most frequently used medicinal plants. This list was superimposed on a vegetation map of Nigeria for the production of a distribution map ahead of an eco-geographic survey for population and phenological studies. Sample sites were defined in east-west directions under different vegetation and land use types. Sample sizes of 50m x 50m quadrant were selected across the vegetation and land use types. Altogether 55 samples quadrats were recorded across the zones; Lowland rainforest (20), Derived savanna (16), Sudan savanna (13) and Guinea savannah (6). A total of 196 individuals were recorded across the four ecological zones, rainforest 66 (33.67%) and least in Sudan savanna 13 individuals (6.63%). On land use basis, plantation forest recorded the highest in the lowland rainforest zone and least in sacred groove with similar trend in Derived savanna. In Guinea savanna, farm lands had the highest number of individuals while forest plantation accounted for the highest in Sudan savanna. Flowering duration varied greatly, ranging from (8.42 ±0.83) days to (45.25 ±5.77) days. Fruiting patterns ranged between (14.44± 4.28 to 145.87± 8.76) days. The need for adequate phenological information ahead of ex-situ conservation programme is desirable. Low stocking density observed across the range and land use types is implicated for holistic conservation strategies and sustainability
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    Local depletion of two larger Duikers in the Oban Hills Region, Nigeria
    (Blackwell Publishing Ltd, 2012) Jimoh, S. O.; Ikyaagba, E. T.; Alarape, A. A.; Adeyemi, A. A.; Waltert, M.
    Across West and Central Africa, duikers are important for trade and consumption; their populations are expected to become depleted. Reliable data on their status are scanty in Nigeria. We assessed duiker populations in the Oban Sector of Cross River National Park through diurnal and nocturnal surveys along 32 transects of 2 km each. After 508-km survey effort, only Ogilby’s duiker (Cephalophus ogilbyi) and blue duiker (Philantomba monticola) were recorded. Using habitat as a covariate in modeling detection probability in DISTANCE 6.0, we estimated densities for the blue duiker ranging from 15.5 (95% CI: 7.8–30.9) in the core, 5.8 (CI: 2.6–12.9) in the buffer and 0.9 (CI: 0.09–10.1) km² in farm fallow to no duikers in the plantation. For Ogilby’s duiker, densities ranged from 1.6 (95% CI: 0.7–3.7) km² in the core, 2.0 (CI: 0.8–5.1) in buffer to no duikers in farm fallow and plantation. The apparent absence of yellow-backed and Bay duikers may indicate local depletion. We call on all stakeholders to rise up to the challenge of rescuing this biological hotspot in Nigeria from further degradation and species loss through improved funding for well-equipped field staff and institutionalized community wildlife management