The effect of warning signs on the presence of snare traps in a Ugandan rainforest.

Since chimpanzee ( Pan troglodytes ) conservation often involves local human populations, conservation strategies must consider psychological factors that impact their behavior. In Budongo Forest, Uganda, for example, local communities commonly engage in snare trap (hereafter: snare) setting for wild meat. This illegal activity posits a substantial threat to wild chimpanzees, causing permanent wounds or death for those who are snared. Despite various schemes previously implemented to address snare setting-an activity that is fueled by poverty, the problem and its detrimental impact on chimpanzees persists. Here, we experimentally tested a novel intervention, a systematic display of specially designed warning signs aimed at local poachers. We monitored the presence of snares before and after introducing these signs over a total period of two years and compared it with that of a similar sized control area with no intervention. Results show that snares were less likely to be present during the "sign" period than during the "non-sign" period in the experimental but not in the control area. We discuss the potential of this cost-effective intervention for limiting illegal activities that pose a severe threat to chimpanzees and other species inhabiting tropical forests.