- Despite new research that doubled the estimated number of orangutan living in Sumatra's rainforests, the great red ape is still "on the road to extinction", say the authors of the study.
- In a statement published this week, the authors warn that the Sumatran orangutan faces extreme threats from habitat destruction and hunting.
- The raised population estimate does not mean orangutans are any less endangered than previously thought.
Despite new research that doubled the estimated number of orangutan living in Sumatra’s rainforests, the great red ape is still “on the road to extinction”, say the authors of the study.
In a statement published this week, Serge Wich of Liverpool John Moores University and Ian Singleton and Matthew Nowak of the Sumatran Orangutan Conservation Programme warn that the Sumatran orangutan faces extreme threats from habitat destruction and hunting. The raised population estimate does not mean orangutans are any less endangered than previously thought.
“Whilst many newspaper headlines have tended to focus on the new larger numbers, and some readers may interpret the new estimates as an indication the species’ population has increased, the reality is the complete opposite, as overall numbers continue to decline dramatically,” write the researchers, all of whom were co-authors on the Science Advances study published last week.
“The new numbers do not reflect any real increase in population or expansion of their habitat. On the contrary, they reflect only the results of a far more intensive, systematic, and comprehensive survey than has ever been carried out before, and hence far more accurate and reliable data than ever before. The overall trend in both numbers and habitat is still very much downward.”
The authors highlight several specific threats, including conversion of habitat for plantations and agriculture, roads that open up previously inaccessible areas to deforestation, and persecution by humans. They cite the risk presented by Aceh’s proposed spatial plan revision, which could grant mining, logging, and plantation concessions in the protected Leuser Ecosystem.
“A prime example is one of the most pressing dangers to Sumatran orangutans, namely a new spatial land use plan being implemented by the Government of Aceh Province since 2013,” they write. “Most of the Leuser Ecosystem (86%) sits within Aceh Province; however, Aceh’s current Spatial Land Use Plan completely ignores the existence of this Nation Strategic Area. The Aceh Spatial Land Use Plan therefore effectively opens up vast swathes of Sumatran orangutan habitat for new plantation, timber and mining concessions, while also potentially legalizing numerous new roads being cut through and further fragmenting its forests.”
“If this plan is not quickly revoked and replaced by a fully legal alternative, the prospects for all of Sumatra’s iconic megafauna, not just the Sumatran orangutan, but also the equally endangered Sumatran tiger, rhino, and elephant, looks extremely bleak.”
The authors conclude that up to a third of Sumatra’s surviving orangutans could be wiped out by 2030 unless “drastic measures” are taken.
“By far the simplest and most cost effective way to prevent the extinction of the Sumatran orangutan is to fully protect the Leuser Ecosystem. Aside from its orangutans the Leuser Ecosystem represents the only real hope for the survival of Sumatran tigers, rhinos, and elephants as well. An intact Leuser Ecosystem is also essential for the livelihoods and long term prosperity of Aceh’s human population too,” said Singleton.
“The Leuser Ecosystem is simply far too important to be put in jeopardy by a spatial land use plan that everyone, from National Government to the Government of Aceh itself has publicly acknowledged is illegal. To save the Sumatran orangutan we simply have to save the Leuser Ecosystem.”