Interactions Between Chimpanzees (Pan troglodytes schweinfurthii) and Cattle (Bos taurus) in the Issa Valley, Western Tanzania.

Wildlife habitats are being degraded globally due to human activities. Pastoralism in Africa has been described as a major threat to habitats and a source of wildlife-livestock interactions and conflict. Chimpanzees in particular are affected by the use of land for livestock, most notably where cattle trample terrestrial food sources and may act as potential reservoirs of disease. Yet, despite extensive study of wild chimpanzees across their distribution, no detailed behavioural observations of chimpanzee-cattle interactions have been described. We report ten direct chimpanzee-cattle encounters that occurred from 2019-2021 in the Issa valley, Tanzania. We observed more interactions in the dry season, and these prompted more vigilance by chimpanzees than wet season interactions. The distance between chimpanzees and cattle may also affect chimpanzee behavioural responses. Our observations suggest that (1) chimpanzees remain vigilant but otherwise only minimally change their behavioural reactions towards cattle in ways that depend, at least in part, on chimpanzee party composition, with males reacting more overtly than females and (2) chimpanzees exhibit more aversive behaviour when cattle are accompanied by herders and dogs. [ABSTRACT FROM AUTHOR]