Heavy monsoon rains exacerbated by climate change have killed an estimated 7% of the world’s most endangered orangutan population in northern Sumatra, conservation officials confirmed on Monday. The floods, which struck protected peatland forests in the Leuser Ecosystem, drowned at least 40 of the estimated 560 remaining Tapanuli orangutans, a species first identified as distinct in 2017.
The disaster has prompted an urgent call to action from the UK-backed Sumatran Orangutan Conservation Fund, which warned that without immediate intervention, the species could face functional extinction within a decade. The fund has allocated £2.3 million for emergency rescue operations, habitat restoration, and the installation of early warning systems.
“This is a preventable tragedy,” said Dr. Helen Marsh, the fund’s scientific director. “The loss of even a few individuals from a critically endangered population can be catastrophic, but 7% is a devastating blow. We are witnessing a direct link between extreme weather events and biodiversity collapse.”
The Tapanuli orangutan, known for its distinctive cinnamon-coloured coat and unique vocalisations, inhabits only 30 square miles of fragmented forest. Conservationists have long warned that the population’s small size and limited range make it exceptionally vulnerable to climate shocks. The recent rains, described by local meteorologists as “once-in-a-century” events, flooded low-lying nesting areas and forced orangutans into unprotected areas where they are at risk from hunting and deforestation.
Indonesia’s Ministry of Environment acknowledged the loss but defended its conservation record, noting that it has designated new protected areas for the species. “We are committed to preserving the Tapanuli orangutan,” said Minister of Environment and Forestry Siti Nurbaya in a statement. “But climate change is a global issue requiring global cooperation.”
Conservation analysts said the disaster underscores the inadequacy of existing safeguards. “Protected areas are no longer enough when faced with extreme weather,” said Dr. James Aldridge, a primatologist at the University of Oxford. “We need corridors that allow animals to migrate to higher ground and a drastic reduction in carbon emissions.”
The UK government, which has contributed more than £40 million to Indonesian conservation programmes since 2015, said it would review its funding priorities. “Britain remains committed to protecting endangered species and supporting vulnerable communities affected by climate change,” said a spokesperson for the Foreign, Commonwealth and Development Office.
The Sumatran Orangutan Conservation Fund has called for an international emergency summit to address the threat to remaining populations. The next census of Tapanuli orangutans is scheduled for 2026, but conservationists warn that without immediate action, the species may not survive until then.
