The palm oil industry has been blamed for mass orangutan die-offs, as the relentless and often unregulated pursuit of palm fruit leads to deforestation and wildfires throughout the island of Borneo and other areas.

But humans killing orangutans — for food, for self-defense, to keep them out of farms, and for mere sport — may be an even more serious threat to the species, according to a new and comprehensive analysis published in the journal Cell Biology of Borneo orangutans by a team of researchers from 38 international institutions.

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The team studied data from 36,555 orangutan habitats and estimated that there was a decline of 148,500 animals between 1999 and 2015, leaving the population across the island at 148,000.

The World Wildlife Fund argues that the Borneo orangutan population is even lower, numbering around 105,000.   

Surprisingly, the team discovered that the orangutans were declining in forested as well as deforested areas, according to National Geographic.

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This insight suggests that factors outside of habitat loss from industrial activity are endangering the species.

Researchers found that since diseases like Ebola weren’t behind the decline, humans must be killing orangutans at previously underestimated rates.

"Sometimes people kill orangutans because they're fearful. We have to convey that they're not dangerous. The chances they'll attack are very small," Serge Wich, co-author of the study from the Liverpool John Moores University, told Nat Geo.

The Indonesian and Malaysian governments, which control Borneo, are developing plans to protect orangutans, Nat Geo reports.

The focus of the effort will be on habitat recovery and conservation to ensure that orangutans are shielded from mining, palm oil, logging, agriculture, and other industries, according to the New York Times.

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But the team of researchers believes that this plan can only be successful if campaigns to deter the intentional slaughter orangutans are enacted.

“Orangutans are flexible and can survive to some extent in a mosaic of forests, plantations and logged forest, but only when they are not killed,” Serge Wich, a professor at Liverpool John Moores University in Britain and a member of the research team, told the New York Times.

“So, in addition to protection of forests, we need to focus on addressing the underlying causes of orangutan killing. The latter requires public awareness and education, more effective law enforcement, and also more studies as to why people kill orangutans in the first place,” he added.

Global Citizen campaigns on the UN's Global Goals, which call for reforestation and animal conservation. You can take action on this issue here.  


Defend the Planet

The Surprising Reason 150,000 Orangutans Have Died in Borneo

By Joe McCarthy