 The range of wild elephants in Sabah and Kalimantan seems to have expanded very little in the past 100 years despite access to suitable habitat elsewhere on Borneo.Borneo's soil tends to be young, leached, and infertile, and there is speculation that the distribution of wild elephants on the island may be limited by the occurrence of natural mineral sources.In 1992, the estimated elephant population size in Sabah ranged from 500-2,000 individuals, based on survey work conducted in the Tabin Wildlife Reserve, in Lower Kinabatangan District and in the Deramakot Forest Reserve.