Hunting, wildlife trade and human-wildlife conflict are main driver orang-utan loss

Posted on: September 28, 2018

Palm oil and pulp are also a major driver, but not the only one cause.

Facts on Borneo Orang-utan population and palm oil.

Bornean orang-utan populations between 1999-2015 declined by 100,000 animals. The species is Critically Endangered under the criteria of the Red List of the IUCN (meaning that at least 80% of the total number has disappeared in 3 generation times, or 75 years for this species).

  • Previous estimates are larger than past estimates because many new areas that had never been surveyed before revealed orangutan presence, but this does not change the trend of declining numbers.
  • The majority of orangutans are found outside of primary and protected forests. They are mostly occurring in degraded forests and selectively logged forest.
  • About half of Borneo orang-utans live in areas open for development or that are already industry concessions.

Hunting and forest conversion are the two major threats for orang-utan long term survival.

  • Non land-use drivers such as hunting, wildlife trade and human-wildlife conflict are main driver orang-utan loss. Even low rates of killings have a high impact due to the species’ slow reproductively rate.
  • Human population densities has a negative influence on orang-utan numbers.
  • Land clearance for industrial and small-holder plantations such as for palm oil and pulp are also a major driver of extinction in agriculture areas (about half of the original orangutan range). However, orangutan populations in areas with unsustainable natural resource use show the highest decline in orangutan numbers. Habitat loss also has a negative impact on population viability – populations are considered non-viable under 100 animals.

Estimates of future orang-utan loss based on forest cover - 43,300 orang-utans during next 35 years (or about half of the current number) - underestimated as they do not include non-land use based impacts.

Protecting forest alone is insufficient. Successful orang-utan conservation needs landscape approaches addressing orang-utan killings and habitat connectivity in effective partnerships with local communities, public and private sectors.



Voigt et al 2018

Sephar et al 2018

Santika 2017