Four days of extreme rain killed 7% of world's rarest orangutans, study says

A recent study indicates that four days of extreme rain and landslides in Sumatra, Indonesia, last November killed approximately 7% of the world's rarest orangutans. Researchers estimate that 58 of the less than 800 critically endangered Tapanuli orangutans perished due to the weather event, which was exacerbated by Cyclone Senyar. The study's authors state these figures are conservative and do not account for indirect impacts like canopy damage or reduced food availability. This extreme rainfall event directly threatened the survival of this great ape population, highlighting the vulnerability of endangered species to climate change-induced weather events.

Extreme rainfall and landslides in North Sumatra, Indonesia, in November 2025 killed 58 critically endangered Tapanuli orangutans, representing 7% of the species' total population. This event, fueled by climate change which intensified rainfall by up to 50%, also destroyed over 8,300 hectares of their forest habitat. Scientists attribute this loss to a climate-induced landslide and express grave concerns for the species' survival, as annual losses of just 1% could lead to extinction. Researchers are calling for an immediate moratorium on habitat-degrading activities and the expansion of protected areas. The Indonesian government has temporarily paused industrial activity in the affected region to assess the situation and determine long-term survival strategies for the Tapanuli orangutan.