Fragmentation and its Significance on the Conservation of Proboscis Monkey (Nasalis larvatus) in the Lower Kinabatangan, Sabah (North Borneo)

Abstract

Timber extraction from the lowland forests of the Lower Kinabatangan floodplain was widespread since the early 1980s and was the major threat to Nasalis larvatus populations. Since then, much of the region has been clear-felled to make way either for cocoa and oil palm plantations or for smaller government-sponsored farming projects. Such clearances not only led to a severe loss of habitats for N. larvatus, but also fragmented the remaining forests. Then beginning in the early 1990s, interests and the relative ease in viewing proboscis monkeys and other wildlife in the Lower Kinabatangan led to a booming tourism industry in parts of the region. This further fragmented N. larvatus habitats and threatened their survival, particularly given that the prime areas for tourist accommodations and associated facilities typically comprising riverside habitats are critical to the species. N. larvatus sleeping sites are determined by the presence of standing trees adjacent or overhanging large water bodies; therefore, loss of those trees or loss of access to those trees have several socio-ecological and conservation implications. Here I describe fragmentation of N. larvatus habitats in the Lower Kinabatangan and the implications of such fragmentations on their long-term survival.