Differential impact of bushmeat hunting on monkey species and implications for primate conservation in Korup National Park, Cameroon

Abstract

Bushmeat hunting is one of the primary threats to many large-bodied vertebrate species in African forests. However, species vary in their degree of vulnerability to hunting. We investigated the impact of hunting on monkey species in Cameroon’s Korup National Park (KNP) and examined how vulnerability to hunting varies among species. Data on primate abundance and hunting intensity were collected along 10 line transects, distributed across three survey areas in KNP. We assessed how the relative abundance of seven monkey species spatially varied between heavily and lightly hunted areas and evaluated temporal changes in the relative abundance and proportional representation of these species at a single hunted forest site and in bushmeat harvests. The putty-nosed and mona monkeys are most tolerant to heavy hunting pressure whereas the crowned monkey, drill, and red colobus are among the most vulnerable. At our heavily hunted survey site, the overall relative density of monkey groups increased through time but primate species richness declined. The proportional representation of Cercopithecus species, especially putty-nosed monkeys, increased through time, possibly due to competitive release. We also observed an increase in the proportional representation of the putty-nosed and mona monkeys and a reduced percent contribution of the red colobus and drill in hunter harvests. We conclude that hunting is driving some of Africa’s most threatened primate species (e.g., Preuss’s red colobus and the drill) to local extinction in KNP. We discuss intrinsic factors of species that might influence their degree of vulnerability and strategies to improve protection efforts in KNP.