Niche segregation among three sympatric species of squirrels inhabiting a lowland dipterocarp forest, Peninsular Malaysia

Abstract

Niche segregation among three sympatric species of squirrels, Callosciurus notatus, C. caniceps and Sundasciurus lowii inhabiting a lowland dipterocarp forest was studied in the Ulu Gombak Forest Reserve, Selangor Darul Ehsan, Malaysia. Diurnal activity of the three species had two peaks. Sundasciurus lowii and C. caniceps were more restricted in vertical space, concentrated mainly at lower tree heights, whereas C. notatus was slightly less restricted. Sundasciurus lowii were more selective in their diet: bark was the main food item. The two Callosciurus spp. took a variety of food items, although fruit was the major component. The niche breadth values in diurnal activity patterns, vertical space uses, and food preferences revealed that C. notatus was a generalist compared with the other two species. Differences in selection of tree species rather than food item may be the main factors that determine niche occupancy for the three species of squirrels in the study area.