Persistence of Primate and Ungulate Communities on Forested Islands in Lake Kenyar in Northern Peninsular Malaysia

Abstract

As more rivers in Southeast Asia’s forested landscapes are dammed, artificial land-bridge islands are becoming more ubiquitous. While the mammal faunas on these islands are poorly studied, they provide unique opportunities to investigate the impacts of fragmentation and isolation on insular biota. During the course of a 60-day survey of small (50 ha) forested islands in Lake Kenyir, Peninsular Malaysia, four primates and three ungulate species were detected on these islands, while the entire complement of six primates were found at nearby mainland sites. Five ungulates were detected on mainland sites. Notably, white-thighed surili (Presbytis siamensis) and white-handed gibbon (Hylobates lar) were found to have persisted on islands as small as 1.1 ha two decades post-isolation, although no ungulates were observed on the three smallest (