Soendjoto, Mochamad Arief; Alikodra, Hadi Sukadi; Bismark, Muhammad; Setijanto, Heru
Description:
The daily activities of the proboscis monkey (Nasalis larvatus Wurmb) living in rubber forests are poorly understood. The objectives of the research were to study its daily movement pattern and to determine the time proportion of daily behaviors. The movement of the monkeys was followed by researchers on foot. The behaviors were observed by scan technique in 15 second intervals for 30 minutes. In rubber forests, lowlands (baruh) were places where the monkey began and ended daily movements and also conducted most activities. Most inter-water movements of the monkey (about 70%) were conducted twice a day. Statistically, movement distance and rainfall were negatively and significantly correlated (ґs = -0.58; p < 0.05; n = 14). The monkey spent more time for feeding in the morning and afternoon, and resting at midday. Most behaviors of feeding, resting, playing, and grooming (84.01%) were conducted at a tree height of less than 15 m. The monkeys moved farther during the dry season to get water and did activities in accordance with height strata to get various foods, avoided disturbances, and got comfortable and safe places.