#WildlifeWednesday: Tarsiers

The Orangutan Foundation manages a tropical forest research station in Tanjung Puting National Park, Indonesian Borneo. Pondok Ambung Research Station is used as a base from which our field staff, students and international researchers can learn more about the flora and fauna of Borneo’s forests.These studies are vital when implementing strategies to best conserve rainforest habitat in this area.

We’ve just received an exciting report from our research manager on tarsiers.



  • There are 10 known species of tarsier, all of which are found in Southeast Asia.
  • Tarsiers are the only carnivorous primate, primarily feeding on insects, but have been recorded to feed on small birds, bats, frogs, crabs and even snakes!
  • Tarsiers are small primates, averaging around just 13cm in length.
  • They are nocturnal, using their large eyes and ears to hunt for prey at night.
  • Their spines are specially adapted to allow them to turn their heads nearly 180° in each direction, perfect for locating prey.
  • Tarsiers move by leaping; Bornean tarsiers have been recorded to jump distances over 5m!
  • They are sexually dimorphic: males are larger than females.
  • Tarsiers have been known to live for up to 16 years.
  • They are generally found no higher than 2m above the forest floor.
  • They tend to live in small groups of around 3 individuals.
  • Tarsiers mark their territory with scent – using their urine!

A Tarsier is a primate which inhabits a range of different forest types. Their taxonomic classification is as follows:











The species our staff studied is known as the Bornean Tarsier (Tarsius bancanus boreanus). Bornean tarsiers are widespread throughout the island of Borneo. Listed by the IUCN as “Vulnerable”, Bornean tarsiers are threatened by the risk of extinction in the wild, as a result of habitat loss.

A population exists within the forests of Tanjung Puting National Park. Our field staff have conducted surveys to track this lesser-known species of primate. Locations where tarsier activity was identified were tracked using GPS. Our staff directly encountered two tarsiers, with 10 other indirect encounters from identifying their scent - left with urine.

All traces of tarsiers were found either near the river or in swamp forest, as this is where tarsiers obtain most of their food. Supporting other research, the two tarsiers spotted were found only in small trees, no higher than 2m from the ground.

Field staff reported heavy rain during tarsier observations, which made it difficult to spot and follow them in the dense vegetation.

It is vital we conserve these types of habitat for tarsiers by preventing human activity in this area of protected forest which leads to habitat loss. Limiting the amount of tourism in this area would also be beneficial so the area can be better managed.

Want to learn more about our research programme? Watch this short clip:

"Us and not us" by Ashley Leiman - Director of the Orangutan Foundation

Ashley Leiman OBE, director of the Orangutan Foundation, explores the complex relationship between man and our closest relatives – the great apes

Please see here : The Biologist Vol 61(2) p12-16 , for the full article.

" The great apes are often perceived differently to other animals. In many cases, it's the simple physical resemblance – we look alike – that's enough to affect how people think and feel about them. No other group of animal has the same attributes that strike a chord with people: hands with nails, eyes that mirror our own, and rich social and emotional lives. Despite this, the 21st century may see the extinction of one of mankind's closest living relatives...

Screen Shot 2013-10-25 at 09.51.11

[ ]...But there are two sides to our perception of apes. While one side emphasises the similarities, the other side emphasises the differences, how the apes are almost but not quite human. This duality occurs across the world, but is perhaps strongest in the west.

Joson, 4 year0ld  rescued orangutan




[ ]...No one is deliberately trying to wipe out the great apes. The present situation shows little more than a lack of care, both nationally and internationally. This is the point where western and indigenous attitudes to the great apes intersect. The fate of the apes rests finally with the inhabitants of ape-habitat countries, be they individuals, communities or governments. However, the west or developed world has a duty of care, for it's the western world order (and its demand for products and raw materials from ape habitats) that has given rise to so many of the problems the apes face.

Bornean orangutan by Ian Wood

"As long as they [apes] are able to roam the earth, hooting, leaping, munching, breaking branches, beating their chests, or simply sitting gazing quietly into the sunset, they will act as a perpetual and vital reminder that we are, after all, little more than brainy, naked apes." (Morris & Morris, 1966). "


Please consider donating to the Foundation here... You can contact us - Ashley and the team - on

Trapped Wildlife

Releasing caged wildlife is rarely anyone’s idea of fun. Panic-stricken animals tend to lash out and they don’t have claws, teeth and talons for nothing. Which is why, yesterday, finding an eagle, a snake and two macaques caught in fish traps provided a challenging finish to the day. As always, I must apologise for the photos; but this time we did have a good excuse; we were all a bit too busy to take photos. So, thank you Rene (a peat forest researcher) for taking the ones below. The fish traps were made of a wooden frame wrapped in netting with an inverted slit through which fish can enter but can not escape. Because the water level in the Mangkung River, the Lamandau Wildlife Reserve, has dropped so much the traps were exposed and the fish inside had obviously tempted the monkeys and the crested-serpent eagle in for an easy meal. Certainly, I have never seen animals caught in them before.

Jak, the Lamandau Patrol Manager and I tackled the eagle first, only to find there was a small python in the trap as well. I was certain that as we cut away the netting the eagle would either peck or slash with its talons, which were wrapped in the netting. Amazingly, once the roof was cut away the bird freed its feet and flew out right in front of our faces, without scratching either of us.

Trapped Eagle

Crested serpent-eagle caught in a fish trap (photo by Rene Dommain).

The python was half way through the netting but having gorged on the trapped fish had a bulge three quarters of the way down its body, which would not fit through the mesh. Jak was all for leaving it and I have to say as its head twisted around I thought he had a point. However, as it was, the snake would be a sitting target for the next eagle to come along. So trying to keep the sharp edge away from its skin, I slid my knife in between the snake and the netting and cut it free. Great, we were now in the water with a python and neither of us wanted to think about crocodiles!

Trapped juvenile macaque

Juvenile macaque caught in a fish trap - once freed he swam away (photo by Rene Dommain).

The macaques were about 100m downstream. In one trap there was a juvenile and on the opposite riverbank, an adult female, thrashing around madly. We were able to free the youngster and I swam over to cut out the female. Again, having some experience of macaques, I thought as soon as the top was open she would come flying out and bite. My dulcet tones did nothing to calm her and, as I cut away each side, she would retreat into the opposite corner ensuring she was always under netting until the whole top was cut off. Only then did she come out.

It was obviously our lucky day for instead of flying out as predicted she actually dove down and swam away under the water. We saw her pop up and climb out, maybe, 15m away.

Four animals released without injury to either them or us. Not bad. Then I scrapped all the skin off my shin climbing back into the boat!

Nancy M., thank you very much for your donation of $50, that you made at the end of April, your support is much appreciated.

"We are participating in WildlifeDirect's business strategy. Please help us by taking this user survey, thank you"

WD user survey