Impact of Gun-Hunting on Diurnal Primates in Continental Equatorial Guinea
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Bushmeat hunting is threatening wildlife populations across west-central Africa, and now poses a greater threat to primates than habitat loss or degradation does in some areas. However, species vary in their abilities to withstand hunting, either because hunters target them differentially or they vary in their vulnerability to a given level of hunting. We studied the impact of current levels of gun-hunting on diurnal primate species in the little-studied Monte Mitra area of Monte Alén National Park, continental Equatorial Guinea. Most bushmeat is currently trapped, but gun-hunting is increasing as shotguns become more available and affordable, allowing targeting of arboreal as well as terrestrial prey. We collected data over 15-mo, via hunter interviews, gun-hunter follows, an offtake survey recording 9374 individuals, and primate surveys covering 408 km of line transects in 2 sites with differing gun-hunting histories. Inside the park, where gun-hunting pressure was recent and light, we found high primate diversity, density, and biomass, with black colobus (Colobus satanas) particularly abundant at 57 individuals/km2. However, around the village, where gun-hunting was longer-established, though other species such as the guenons still persisted (albeit at lower densities), Colobus satanas were virtually absent. Being slow and large-bodied, Colobus satanas are preferred and susceptible prey, and an early indicator of overhunting. Monte Alén National Park is currently an important stronghold for primates, particularly Colobus satanas, but regulation of the trade and enforcement of hunting bans in the park are urgently needed to safeguard their future and that of other vulnerable species.
Keywordsbushmeat Colobus satanas Equatorial Guinea gun-hunting impact primates
We thank the Ministry of Forestry and Infrastructure, INDEFOR and ECOFAC in Equatorial Guinea for supporting our research and Michael Allen for his help and advice. We thank Guy Hills Spedding, Brigid Barry, Bienvenido Ondo Ndong, Santiago Eñsen, Pedro Nsue Nseng, and Antonio Ayong Nguema for their assistance in data collection. The Economic and Social (ESRC) and Natural Environment (NERC) Research Councils of the United Kingdom, Conservation International through the CARPE programme, and the European Union through ECOFAC/AGRECO funded the study. This study is a contribution to the ZSL Institute of Zoology Bushmeat Research Programme.
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