Stock assessment of large mammals in Nigerian wooded savanna and its management implications

Abstract

Assessment of canopy and ground cover was carried out in two vegetation types at Yankari Game Reserve (YGR) using the rapid field technique of Riney (1963). Animal population was enumerated by two census methods, namely fixed transect belt (FTB) and King's census (KC) methods. The population of large mammals, enumerated by these methods, was compared for the upland savanna (US) and riparian woodland (RW) of the reserve. Morning and evening counts of animals were also compared between vegetation types. Percentages of perennial grass, litter and browse plants were higher in the RW than in the US. Consequently, RW had better soil protection and ecological stability than US. Total animal number in RW was also higher than in US, probably due to the fact that RW provided better shelter and contained more food and water than US. The FTB method of obtaining a census indicated that waterbuck, with a population of 5067, was the most abundant species during the evening count along the RW. The KC method estimated the population of this species to be 8815. Elephant and roan antelope appeared to be present during evening counts whereas the buffalo population was higher ( P < 0.01) in the morning than in the evening. The management implications of the two census methods are discussed, both in regard to their usefulness in long term ecological monitoring, and in determining the conservation status of habitats and animal population in African savanna woodlands.