Conservationists have made the orangutan a symbol of what will be lost if we do not halt tropical deforestation. But data tell a more nuanced story. In Kalimantan on the island of Borneo, humans murder so many orangutans each year (on average, between 1,970 and 3,100 annually) that this rate of killing is enough to tip the species towards inexorable extinction. These numbers are part of a new study just published in the journal PLoS One and co-authored by a group of Nature Conservancy scientists, who interviewed almost 7,000 people from 687 villages in Kalimantan.

There is little hope of saving a species like the orangutan unless we know why it is in peril. Unfortunately, conservation often latches onto ideas without much evidence. For example, it used to be thought that orangutans needed pristine old growth forest to thrive. Recently, however, large populations of orangutans have been documented in highly degraded forests. The argument about “save the rainforest to save the orangutan” suddenly got a little weaker.

Of course, massive deforestation is responsible for severe declines in orangutan populations. And the encroachment of villages into forests has put orangutans in more frequent contact with humans, and hence more susceptible to being killed by humans. This orangutan story is not so unique, as increased human-wildlife contact is being seen on every continent in the world: grizzly bears and wolves in the United States, pumas in South America, elephants and tigers in India, and orangutans in Indonesia. Friends of mine with direct personal experience wonder how many endangered stellar sea lions in Alaska are shot by people — and I personally have seen fisherman shoot at marine mammals (illegally). Humans have been hunting and killing wild animals for tens of thousands of generations, and we should not be surprised by this type of behavior.

Certainly, when there is human-wildlife conflict, strict laws do not appear to be the answer. It is pretty hard to prove guilt and then prosecute a human for killing a protected species. Indonesia’s national law outlawing any killing of orangutans obviously has not been much of a deterrent. The scientists leading the study of orangutan killing suggest that the only effective solution is likely to be cultural and social persuasion. Optimistically, they do not think it will take much to get people to change their behavior in this particular case.

Finally, this story of killing as a major source of orangutan risk should give all conservationists pause. Go to the websites of the premier orangutan conservation NGOs and see if there is any mention of killing on the scale discovered in this recent study. Even within the Conservancy, where we have been working in Indonesia for over a decade, one has to wonder why did it take us so long to uncover this threat to the orangutan?

The answer is perhaps not so bad — it is because we, like all conservationists, are action-oriented and eager to implement strategies based on conventional scientific wisdom. But the startling discovery of a murderous killing rate of orangutans should remind us to never accept conventional wisdom as fact, and to always be collecting fresh data and conducting new studies.

(Image credit: davidandbecky/Flickr through a Creative Commons license.)



  1. We are certainly rapacious, aren’t we? Discouraging orang killing by making them a cultural symbol or pointing out their innate Grace probably will not be greatly effective in this age of overweening cynicism. We kill one another at a rate that would threaten extinction if there were not so many of us.

  2. Yes, there is a ‘killing’, and we all could see the proof when the first rehabilitation start in 1970 in Sarawak and Indonesia. One baby at the centre means one orang-utan mother died. To date, ‘killing’ process continued because open access to the forest is creating a condition that many orang-utans have been trapped in open areas, causing increased hunting. Moreover, the starved animals wander into the plantation or human settlement and eat anything edible to eat, causing economic loss. They are clever animals, aren’t they? People who encounter with the animals could be scared, and sometimes it could lead to fight or kill. Or company that took orang-utan habitat for their operation silently order to kill the orang-utan that wander in their area. But, be careful with the number or data, and as a scientist we should provide evidences, also the methods in collecting data especially combining the science and social data that needs careful consideration. Maybe the surveyors are not using the communicative way in asking the respondent for the questionnaire, then there is a possibility the respondent lie too. Please bear in mind that the habitat loss is the major cause of population decline, and weak of law enforcement implementation completed the unfortunate orang-utan, that supposedly to protect by law but in reality are not protected at all.

  3. Anyone have any pixar script ideas to market to children what they will miss in their lifetimes if grandma & grandpa continue their last century lifestyle?

    1. Great idea – except let’s do movies and books about what kids can do to save wildlife now.

      1 – Write the Girlscouts and ask them to renounce selling food products with Palm Oil in them; tell them you’d rather eat something else.
      2 – Or, volunteer to preserve large blocks of forest.
      3 – OR, plant plants in your yard.

  4. My takeaway is still “Of course, massive deforestation is responsible for severe declines in orangutan populations”. While it may be only one of many factors, it is very significant, has a dramatic impact, and may be contributing to the other factors by driving them from their natural habitats.

  5. I think it does little for the cause to describe the killing on an orangutan as murder. You can murder another person, not an animal. For conservationists to be taken seriously I think it is important we use appropriate language when reporting on issues and imploring people to change their behaviour.

    1. Does it really matter what word you put on this — the net result is, babies are motherless at a decimating rate — these animals will be extinct in this century if we continue.

      Let’s work with the local peoples to help them learn how to grow, without cutting any more of their forests, and conserve the wildlife that lives there.

  6. I think that people should chip in and help these orang-utans. why cant we eat vegetable oil instead of palmoil is there really a big difference ???

  7. when do these things happen? like when deforestation happens and when the orangtans loose their homes and die?

  8. this is crazy how all of these things are happening like really? what is the point of cutting down all of the trees? if you really look at it … if they cut more trees down then thats the less time that we have to live because they’re cutting our oxygen supply

  9. why? do tthe events in the article occur? like what is the point of cutting down the trees? you really don’t have that much information in this article im doing a school project and when i had read this there is no information in here to help me with my class assiment

  10. If the orangutans are damaging crops or raiding villages, they clearly need to be put down. If they have a baby, put it down with the mother.

  11. Nature Conservancy supports “Back to Nature” cookies, which the fudge mints use Palm Oil and Palm Kernel Oil.

    Palm Oil Plantations – which are created by cutting down forests – are and the associated killing of the mother orangutans — are the main reason Orangutan populations are declining so rapidly.

    Local people will kill the mother orangs as an easy way to kill a whole family, since the babies cannot survive without their mothers.

    Link to the cookies with Palm Oil supported by the Nature Conservancy :

    Here’s one consumer who will not support the Nature Conservancy – until they start doing the right thing: stop participating in products that contain Palm Oil, start putting the forests back – or AT LEAST – conserving the forests that are still standing.

Add a Comment