Please ensure Javascript is enabled for purposes of website accessibility
top of page

Tapanuli Orangtans

Call for a moratorium on development in Critically Endangered Tapanuli orangutan's range

Download SGA statement on the Tapanuli Orangutan 

Tapanuli Orangutan

Tapanuli orangutans and Batang Toru hydroelectric dam

Halt hydropower project to save orangutans, urges scientific review. Misleading claims threaten world’s rarest ape. Fact check and references on key issues available for download here in the IUCN SGA Batang Toru Factcheck Report April 2020:

The Section on Great Apes (SGA) of the IUCN SSC Primate Specialist Group has published a factcheck document assessing claims about the environmental credentials of the Batang Toru hydropower project in Sumatra, Indonesia. The report identifies many inaccurate and misleading statements made by the project’s developers, especially concerning its likely impact on the newly described Tapanuli orangutan species, and reiterates the call for a moratorium on the project while a full and transparent scientific evaluation is conducted.

The Tapanuli orangutan is the most recently identified species of great ape and is critically endangered, with less than 800 individuals in the wild. The hydropower project is situated at a key location for movement of orangutans between their main habitat areas. Concerned about the possible extinction of the Tapanuli orangutan, the SGA called for a moratorium on the project in 2019 to study the impacts and possible mitigating measures. So far, this call has been ignored by the project developers and Indonesian government.

The hydropower company and its supporters claim to make use of the best science to inform the project’s development and minimize impact on orangutans. The SGA fact-checking  report, however, finds a total of 28  statements made by the project proponents to be misleading or inaccurate, based on current scientific knowledge and in some cases the findings in the project’s own environment impact assessment. This analysis seriously undermines the company’s claim that the project can be developed without impact on the orangutan.

The project is currently on hold due to the withdrawal of several international funding institutions, and the current COVID-19 lockdown situation. The SGA feels that this is a perfect opportunity to reassess such large and potentially damaging infrastructure projects and consider whether the anticipated benefits justify the environmental impacts.

“The current global crisis is forcing many sectors to reassess how they operate – high impact development projects such as the Batang Toru hydro plant need to take the opportunity as well,” says Professor Serge Wich, Vice Chair of the SGA and a global authority on the Tapanuli orangutan. “This report shows how misleading many of the justifications for the project have been and strengthens the case for an official halt in activities while a full scientific evaluation takes place.”

The report entitled “Batang Toru Hydropower Project - Factcheck and References on Key Issues” looks at topics ranging from orangutan distribution and behaviour to river flow and regional power supply.

For more information contact Professor Serge Wich at or call +447511059740.

bottom of page