Borneo Elephant :: WLR:- The Borneo elephant also called the Borneo pygmy elephant inhabits northeastern Borneo. Its origin remains the subject of debate. A definitive subspecific classification as Elephas maximus borneensis awaits a detailed range-wide morphometric and genetic study. Since 1986, Elephas maximus has been listed as endangered by IUCN as the population has declined by at least 50% over the last three generations, estimated to be 60–75 years. The species is pre-eminently threatened by habitat loss, degradation and fragmentation.
The Sultan of Sulu introduced captive elephants to Borneo in the 18th century, which were released into the jungle. Comparison of the Borneo elephant population to putative source populations in DNA analysis indicates that the Borneo elephants are derived from Sundaic stock and indigenous to Borneo. The genetic divergence of Borneo elephants warrants their recognition as a separate Evolutionary Significant Unit.
Elephants have been confined to the northern and northeastern parts of Borneo. In the 1980s, there were two distinct populations in Sabah ranging over the Tabin Wildlife Reserve and adjacent mostly logged dipterocarp forest on steep terrain; and in the hilly interior at about 300 to 1,500 m (980 to 4,900 ft) altitude in dipterocarp forest, which was largely undisturbed at the time, and only logged at the periphery. In Kalimantan, their range is restricted to a small contiguous area of the upper Sembakung River in the east.
Previous estimations for the population in Sabah have ranged between 500-2000 elephants. Between July 2007 and December 2008, wildlife biologists conducted an elephant population census in five main elephant managed ranges in Sabah using a systematic line transect survey and a long term monitoring of dung decay rates. They estimated a population of 2,040 elephants. The largest of the five populations inhabits the unprotected central forests of Sabah, a contiguous area of forest which is largely commercial forest, where 1,132 elephants were estimated to remain. Elephant density (elephants per square kilometre) was found to be highest where neighbouring habitat had been destroyed and the remaining elephants squeezed into the remaining forest areas.
The Sultan of Sulu introduced captive elephants to Borneo in the 18th century, which were released into the jungle. Comparison of the Borneo elephant population to putative source populations in DNA analysis indicates that the Borneo elephants are derived from Sundaic stock and indigenous to Borneo. The genetic divergence of Borneo elephants warrants their recognition as a separate Evolutionary Significant Unit.
Elephants have been confined to the northern and northeastern parts of Borneo. In the 1980s, there were two distinct populations in Sabah ranging over the Tabin Wildlife Reserve and adjacent mostly logged dipterocarp forest on steep terrain; and in the hilly interior at about 300 to 1,500 m (980 to 4,900 ft) altitude in dipterocarp forest, which was largely undisturbed at the time, and only logged at the periphery. In Kalimantan, their range is restricted to a small contiguous area of the upper Sembakung River in the east.
Previous estimations for the population in Sabah have ranged between 500-2000 elephants. Between July 2007 and December 2008, wildlife biologists conducted an elephant population census in five main elephant managed ranges in Sabah using a systematic line transect survey and a long term monitoring of dung decay rates. They estimated a population of 2,040 elephants. The largest of the five populations inhabits the unprotected central forests of Sabah, a contiguous area of forest which is largely commercial forest, where 1,132 elephants were estimated to remain. Elephant density (elephants per square kilometre) was found to be highest where neighbouring habitat had been destroyed and the remaining elephants squeezed into the remaining forest areas.
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