ABSTRACT
The tropical rain forests of Southeast Asia comprise a variety of habitat types and a great diversity of plant and animals species. All of the diurnal primates in Indonesia are relatively large, and a transect method is suitable for censusing. In actual practice, cutting and measuring trails through the forest is time consuming and severely limits the area that can be censused. All of the diurnal primates, except the orangutan, are social animals living in troops. The likelihood of detecting all of the troop members during a census contact depends on troop size, visibility characteristics of the habitat, and behavior. Even when density estimates are accurate, total population size estimates can be incorrect when they are based on inaccurate forest area figures. An alternative method of censusing primates is to count all troops in a study area of known size.
