Relative population density of Tarsius Dianae in Man-Influenced habitats of Lore Lindu National Park, Central Sulawesi, Indonesia

Abstract

The aim of this study was to know the impact of human activities on population density of Tarsius dianae by estimating the relative population density in four habitat types differently influenced by man. The study was conducted in the vicinity of Kamarora, at the northeastern boundary of Lore Lindu National Park, Central Sulawesi. Four different habitats were chosen: (H1) primary or old secondary forest; (H2) secondary forest ± 30 years after clearance with small-scale selective logging; (H3) forest with interspersed small coffee and cocoa plantations; and (H4) forest with selective logging and plantations. The tarsiers sleeping sites were determined using triangulation. Relative population density was estimated by measuring the average distances between three nearest neighbors. The results suggest that different human-influenced habitat have different effects on tarsier s density. The smallest distances (116.2 ± 18 m) between sleeping sites, which represent the highest estimated population density (57.1 groups in one square km), were found in habitat type H1, the least disturbed habitat. Estimated population density in habitat type H3 or forest plantations was 38 groups/km2, followed by habitat type H2 or secondary forest with selective logging 36.4 groups/km2, and the smallest population density was estimated at 32.9 groups/km2 in habitat type H4 or forest with selective logging and plantations.