Please check out this recent article from the Guardian regarding unsustainable development in the Batang Toru Ecosystem, home to the only and last habitat of the newly identified yet already Critically Endangered Tapanuli orangutan:
https://www.theguardian.com/environment/radical-conservation/2018/apr/23/worlds-newest-great-ape-threatened-by-chinese-dam
“First of all, we need to ensure that the eastern and western populations in Batang Toru remain fully protected, that is zero habitat loss and zero killing,” said Sumatran Orangutan Conservation Programme (SOCP)‘s Tapanuli Programme Coordinator, Gabriella] Fredriksson. “We also need to ensure that the eastern and western block remain connected. Once the Batang Toru populations are save and secure, reintroduction of the species into its historic range can be considered.”