Interactions between zoo‐housed great apes and local wildlife

Abstract

Although there are published reports of wild chimpanzees, bonobos, and orangutans hunting and consuming vertebrate prey, data pertaining to captive apes remain sparse. In this survey-based study, we evaluate the prevalence and nature of interactions between captive great apes and various indigenous wildlife species that range into their enclosures in North America. Our hypotheses were threefold: (a) facilities housing chimpanzees will report the most frequent and most aggressive interactions with local wildlife; (b) facilities housing orangutans and bonobos will report intermediate frequencies of these interactions with low levels of aggression and killing; and (c) facilities housing gorillas will report the lowest frequency of interactions and no reports of killing local wildlife. Chimpanzees and bonobos demonstrated the most aggressive behavior toward wildlife, which matched our predictions for chimpanzees, but not bonobos. This fits well with expectations for chimpanzees based on their natural history of hunting and consuming prey in wild settings, and also supports new field data on bonobos. Captive gorillas and orangutans were reported to be much less likely to chase, catch and kill wildlife than chimpanzees and bonobos. Gorillas were the least likely to engage in aggressive interactions with local wildlife, matching our predictions based on natural history. However unlike wild gorillas, captive gorillas were reported to kill (and in one case, eat) local wildlife. These results suggest that some behavioral patterns seen in captive groups of apes may be useful for modeling corresponding activities in the wild that may not be as easily observed and quantified. Furthermore, the data highlight the potential for disease transmission in some captive settings, and we outline the associated implications for ape health and safety.

<Note>Bird in the hand: Bossou chimpanzees (Pan troglodytes) capture West African wood-owls (Ciccaba woodfordi) but not to eat

“…Chimpanzees rarely capture an animal without eating it, but this puzzling pattern occurs in both nature and captivity, mostly by youngsters [1][2][3][4][5][6] . At Bossou in Guinea, chimpanzees rarely hunt for meat; their home range presents few suitable prey 7 .…”

Responses toward a trapped animal by wild bonobos at Wamba

“…Data from zoos have shown that captive bonobos are more aggressive toward local wildlife than expected, and the rate of their aggressive interactions is almost the same as that of chimpanzees (Ross et al 2009). Ross et al (2009) reported that all facilities keeping captive bonobos have experienced the capturing of wildlife by bonobos.…”

“…Ross et al (2009) reported that all facilities keeping captive bonobos have experienced the capturing of wildlife by bonobos. The accumulation of reports on hunting or interspeciWc interaction in wild bonobos may lead to a novel understanding of the aggressive nature of bonobos toward sympatric animals including primates.…”

<NOTE>Four Cases of Grooming Sessions between Chimpanzees and Guenons at the Kalinzu Forest Reserve, Uganda

“…Most actors of chimpanzee side are mother and offspring, and all actor of guenon side is solitary male. Because adult chimpanzees tend to be aggressive to other species (Ross et al 2009), guenons probably avoid groups of chimpanzees, especially groups of adult male chimpanzees (but see Hosaka & Ihobe 2015). However, immature chimpanzees have a relatively small body size, and thus guenons may be able to approach non-adult chimpanzees without fear of lethal aggression.…”