BNF Directors contribute to new Orangutan Population and Habitat Viability Assessment


2016 was a significant year for orangutan conservation. The Bornean orangutan was declared Critically Endangered by the International Union for Conservation of Nature (IUCN) as threats to the species have become more severe and scientists have estimated that the population will decline by 86% between 1950 and 2025. Now both species of orangutan (Bornean and Sumatran) are listed as Critically Endangered on the IUCN Red List of Threatened Species.

Between 23-27 May 2016 orangutan conservationists, including Borneo Nature Foundation Directors, Simon Husson and Bernat Ripoll Capilla, participated in an international workshop to conduct a Population and Habitat Vialibilty Analysis (PHVA) for both the Sumatran and Bornean orangutan. The final orangutan PHVA report was released last month.

This is the third PHVA which has been carried out for orangutans; previously in 1993 and 2004. A PHVA looks at current population dynamics, habitat and distribution, and then makes predictions for the viability (capability of surviving) of the population in the future.

Based on the results of the orangutan PHVA 2016, there are currently an estimated 71,820 individual orangutans left on Sumatra and Borneo islands. The current population of Sumatran orangutans is estimated to contain 14,470 individuals in only 2.1 million hectares of forest. While the Bornean orangutan is estimated to have 57,350 individuals in 16 million hectares of forest. Based on these data there is a decrease in the density of the orangutan population on both islands since the last PHVA.

The PHVA has predicted that only 38% of the species will viable in the next 100-500 years. This calls for serious conservation action now to ensure further orangutan population decline is halted and the threats to the species are addressed.

The results of the Orangutan PHVA 2016 will be the main reference in the development of a new Strategy and Orangutan Action Plan (SRAK) 2017-2027 in Indonesia.(DN)

The Orangutan Population and Habitat Viability Asessment 2016 Final Report can be downloaded here