Tapanuli orangutan endangered by Sumatran hydropower scheme.

[Extract:] To the Editor — The Tapanuli orangutan survives today in less than 1,200 km2 of rainforest in northern Sumatra, Indonesia, in an area known as Batang Toru, where it was scientifically discovered1 in 1997. Teeming with endangered fauna and flora, the Batang Toru forest has been partially felled and fragmented and parts of the remainder allocated to agriculture, mining, hydropower and geothermal-energy production. The Tapanuli orangutan is estimated to number just 767 individuals, divided among three subpopulations1. Its total remaining habitat is merely a tenth of the size of Sydney, Australia.