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

Since chimpanzee () 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.