Bonobo habituation in a forest-savanna mosaic habitat: influence of ape species, habitat type, and sociocultural context.

Habituation is the term used to describe acceptance by wild animals of a human observer as a neutral element in their environment. Among primates, the process takes from a few days for Galago spp. to several years for African apes. There are also intraspecies differences reflecting differences in habitat, home range, and ape-human relationship history. Here, we present the first study of the process of bonobo habituation in a fragmented habitat, a forest-savanna mosaic in the community-based conservation area led by the Congolese nongovernmental organization Mbou-Mon-Tour, Democratic Republic of the Congo. In this area, local people use the forest almost every day for traditional activities but avoid bonobos because of a traditional taboo. Because very few flight reactions were observed during habituation, we focused on quantitative parameters to assess the development of ape tolerance and of the tracking efficiency of observer teams. During the 18-month study period (May 2012-October 2013), 4043 h (319 days) were spent in the forest and bonobos were observed for a total of 405 h (196 contacts on 134 days). The average contact duration was stable over time (124 min), but the minimal distance during a contact decreased with habituation effort. Moreover, bonobo location and tracking efficiency, daily ratio of contact time to habituation effort, and the number of observations at ground level were positively correlated with habituation effort. Our observations suggest that bonobos become habituated relatively rapidly. These results are discussed in relation to the habitat type, ape species, and the local sociocultural context of villagers. The habituation process involves changes in ape behavior toward observers and also more complex interactions concerning the ecosystem, including the building of an efficient local team. Before starting a habituation process, knowledge of the human sociocultural context is essential to assess the balance between risks and benefits.