Indonesian Orangutans Face Extinction Due to Extreme Rainfall and Landslides

Jakarta. Extreme rainfall for four consecutive days and subsequent landslides on Indonesia's Sumatra island have pushed the world's most endangered monkey species, the Tapanuli orangutan, closer to extinction, a new study has shown. 

According to the research, 58 Tapanuli orangutans died in a severe weather event in November 2025. The population of these orangutans was around 800. This means 7 percent of the orangutans died in these incidents. 

According to the study's authors, this estimate is also very conservative. It does not include the damage caused to the forest canopy by the rain and the reduction in food sources. 

The Sinyar cyclone, which occurred in late November, caused great devastation in Sumatra. This natural disaster claimed the lives of more than 1,000 people across Southeast Asia, making it the deadliest natural disaster of 2025. 

According to researchers, such extreme rainfall events can directly threaten the survival of orangutans. In the days following the storm, their numbers suddenly decreased, leading to fears that they may have been caught in floods and landslides. 

Co-author of the study, Eric Meijaard, had previously estimated that about 35 orangutans had died. Estimate