Monitoring conservation effectiveness in tropical forests: bushmeat offtake parameters vary more quickly compared to parameters related to the living wildlife community

Abstract

Evaluating the effectiveness of conservation actions in tropical forests is essential. Generally based on the monitoring of living wildlife communities, combination with bushmeat extraction indicators is seldom used. It is therefore interesting to carry out a monitoring of indices related to these two categories of indicators in order to identify indices presenting more temporal variation and allowing for a rapid detection of real changes. Between 2017 and 2020, data on bushmeat offtake were recorded and surveys of wildlife and human activity signs were conducted in a conservation zone in Dja Biosphere Reserve in Cameroon. Data were collected around villages where human pressure is high. Our results show a decline in total biomass and number of animals killed. An increase in numbers of traps set was observed, but there was no notable difference in the mean biomass of a carcass and mean number of hunting trips. Overall, wildlife abundance decreased slightly in 2020, mainly reflecting changes for three species--bay duiker (Cephalophus dorsalis), yellow-backed duiker (Cephalophus sylvicultor) and red river hog (Potamocherus porcus)--which were more abundant in 2018. Regarding keystone species, we noted a slight increase in the abundance of chimpanzees. Patterns of species richness in both study years were similar. These results suggest that bushmeat offtake data may be more informative for early evaluations of the effectiveness of wildlife conservation efforts. This underlines the importance of monitoring bushmeat for the evaluation of wildlife conservation projects in contexts where hunting occurs.