Ranging behaviour and sleeping sites of Macaca fascicularis in Bali Barat National Park, Indonesia

Ranging behaviour and sleeping site selection are important primate behavioural traits likely to vary under environmental changes. We tested the role of ecological (predation avoidance) and anthropic (human proximity) factors in Macaca fascicularis range use, an edge species known to prefer living along forests borders and in the vicinity of human settlements. Data result from 56 day follows of one group of Macaca fascicularis exploiting a human-modified landscape within Bali Barat National Park (Indonesia). Observations allowed identifying and describing 17 sleeping sites and the characteristics of 37 sleeping trees. Despite a large forest area available, the group’s home range centred around human settlements. The home range size, average daily range and daily travel decreased over the study period, while the human presence inside the park increased over the corresponding months. The proximity with humans also influenced the pattern of sleeping sites use; macaques slept more than expected close to human settlements and this tendency increased over the study period. In contradiction with the predation avoidance assumption, macaques did not choose sleeping trees significantly taller and larger than other trees available. We conclude that the observed sleeping site strategy (sleeping near humans) could be advantageous in terms of predator avoidance and proximity with human food, but additional influences should not be neglected.