Except for a handful of recent studies, there has been very little research focusing on the ecology of the Tonkean macaque (1) (4) (7). As a result, there is scant information on this species’ group behaviour, but troops of 10 to 30 individuals, comprising multiple sexually mature adults of both sexes, have been documented (7). Although the Sulawesi macaques are generally considered to be semi-terrestrial (5), the Tonkean macaque appears to spend most of its time moving around in the tree canopy (7). Active during the day, it feeds primarily on fruit, but will also consume leaves, flower-stalks, insects and other invertebrates. In the vicinity of farmland, this species is also known to raid crop plantations for maize, fruit and vegetables, bringing it into direct conflict with human activities (1) (7).