Tag Archives: research

Belantikan’s big ape count

Determining wild population sizes of orangutans and gibbons, both highly arboreal (tree-dwelling) apes species, is a conservation challenge. But, over the years, scientist have come up with methods that enable accurate estimates. For example, with orangutan their nests are counted and with gibbons, it is their songs that are recorded and used.

Bornean orangutan by Ian Wood.

Bornean orangutan by Ian Wood.

We are trying to find out more about the wild ape populations of the Belantikan Hulu region which is part of the greater Belantikan Arut – a spectacular landscape spanning 500,000 hectares across Central and West Kalimantan (Indonesian Borneo). The Belantikan Conservation Programme (BCP) is a joint initiative of Yayorin (an Indonesian NGO) and ourselves.

The Belanitkan Hulu comprises primary and secondary lowland forests, including both recently logged forests and post-logging forests that have since recovered (over the last 35-40 years). The area has ravines, rivers, cliffs and logging roads – all synonymous with Borneo.

There is a large wild orangutan population, which was first surveyed in 2003, and a gibbon population, whose size is unknown. In 2012, The Rufford Foundation awarded funding to the BCP to build a small research station and to commence surveys of the ape species. The research station is now in use by BCP’s field researchers and by a team of biologists from the National University of Jakarta.

Our initial surveys indicate there has been a continuing decrease in the orangutan population over the years. This population was estimated to be the largest population of orangutans existing in the wild outside of the protected area system. In fact, more than 70% of the total Bornean orangutan population in the wild is found outside of designated conservation areas. Hence, it is important to determine the size and distribution of the Belantikan population accurately, and to be able to monitor the current apparent population decline, so that appropriate conservation actions can be taken.

The gibbon survey estimated a density of just over 3 groups per km2, which is considered high. The BCP will conduct further research to determine how orangutans adapt to living in logging forests and to the varying degrees of disturbance. Further studies on gibbons will also survey the wider area and the estimated territory and cruising areas, study group composition as well as changes in habitat conditions between seasons.

We hope to provide you with new and exciting findings from Belantikan as we start to find out more about its forests and what lives within.

We are extremely grateful to The Rufford Foundation and to the US Fish and Wildlife Service Great Ape Conservation Fund for supporting this research project, and to the Arcus Foundation for supporting the on-going conservation project.

Thank you,

Orangutan Foundation and Yayorin (Belantikan Conservation Programme)


Video footage of baby freshwater crocodile

Watch this short clip of a baby tomistoma crocodile, also known as the false gharial. It was taken at Pondok Ambung Tropical Forest Research Station, Tanjung Puting National Park, Indonesian Borneo by Wawan, the Orangutan Foundation’s Finance Office, who was on a logistic run to the field site.  This species of fresh water crocodile is listed as endangered on the IUCN Redlist.


Orangutan Foundation

Universities interested in study at Pondok Ambung please contact Orangutan Foundation

Borneo’s Enchanting Forests

As the UN Year of the Forests 2011 draws to a close Arif Nugroho, the manager of Pondok Ambung Tropical forest Research Station in Tanjung Puting National Park (Central kalimantan, Indonesian Borneo), has sent this interesting report (which is almost poetic in parts) with images about some of the rarer treasures of the rainforest. Over to Arif …….

Welcome the rainy season, welcome beautiful colorful mushrooms

At the beginning of rainy season, we felt spoilt when walking in the forest. There were many different colorful mushrooms, some with striking colors such as bright yellow or orange. They looked like little umbrellas in the ground – so beautiful.

Mushrooms found at Pondok Ambung

Mushrooms found at Pondok Ambung

Mushroom found at Pondok Ambung - Tanjung Puting National Park

Mushroom found at Pondok Ambung - Tanjung Puting National Park




While collecting data on the vegetation with Mas’ud Ashari, a student from the Forestry Faculty at Gajah Mada University, Jogjakarta we found many species of mushrooms. We couldn’t identify them but took images of them. Classification of fungi is always suffering from contradictions because there is a lack of complete knowledge about all the fungal organisms. There is little information reported about mushrooms in Borneo, especially in Pondok Ambung. So the aim of the present investigation was to identify the wild mushroom in Pondok Ambung Tropical Forest Research Station. We found at least 12 different species of wild mushrooms, even if we didn’t identify yet. (Please leave a comment if you can help!).

Frogs: Wildlife under canopy

Night tracking. Walk slowly into forest. Smelling the soil after the rain and listening to nature’s voices. So peaceful. Light your torch around you and find some eyes glowing. Yup, that is way to see a beautiful frog, wildlife under canopy.

Rough-sided Tree Frog

Rough-sided Tree Frog

Dark-eared Tree Frog

Dark-eared Tree Frog

Collet's Tree frog

Collet's Tree frog

Butterflies Covering the Ground

Tanjung Puting National Park (TNTP), has peat swamp forests and  orangutans are a key species. The National Park attracts many tourists mainly to see the orangutans. But there is still lots of other biodiversity. We  are trying to explore  and the more we do we discover awesome wildlife.

Idea Hypermnestra

Idea Hypermnestra


This month looks like a butterflies’ moon. They are so easy to find and watch. On a river bank, among the leaf litter and twigs of trees, there are  various kinds of colorful butterflies. I watched one. Flapping its wings occasionally to shift places, then pauses as if she were sipping something from the soil. I crawled over. Trying to enjoy every detail of its beauty. Wings have colorful patterns and sometimes seem complicated. Some of them show a striking hue. Others are just black and white only. But the pattern remains fascinating.

Based on my observations, the butterflies are very easily found on the edge of the river. Precisely on lands moist but still exposed to sunlight. Several others were observed at the lower canopy of trees or perched in the foliage. I also found butterflies gathered in soil doused with smelling material, like soapy water or rotten fruit.


Check my article (In Bahasa Indonesian) about butterfly of Pondok Ambung TNTP in Biodiversitas Indonesia Magazine Vol. 1 No. 2 Th. 2011. Magazine can be downloaded for free here.

Researching Western Tarsier in Pondok Ambung

Masud  Ashari,  the student from Forestry Faculty, Gajah Mada University, Jogjakarta is at Pondok Ambung to research the population and distribution of the Western Tarsier (Tarsius bancanus Horsfield, 1821) in the lowland forest habitat of Pondok Ambung Tropical Forest Research Station and Tanjung Harapan, Tanjung Puting National Park, Central Kalimantan.

Tarsius bancanus at pondok Ambung

Tarsius bancanus

Over 15 days he made 11 transects line and 23 plots of vegetation analysis and recorded 8 points of Tarsiers. This wasn’t actual observations but encountering their smell. Tarsiers produce a secretion from a gland aroung their genitals for marking their homerange. Each point recorded shared similar characteristics. Sapling trees up to pole size, moderate to high vegetation density, temperature between 24-27 ° C, and humidity between 60-65%. Tarsier prefer this habitat because the conditions allow for easy locomotion (leaping between treest), feeding, playing, perching to prey etc.

Thank you,


More news on orangutans later this week…

Please support our work by making a donation today via our website or by calling 0044 (0)20 7724 2912 – thank you.

Butterflies and birds – diversity of life!

The Orangutan Foundation is proud to support Indonesian students conducting research at Pondok Ambung Tropical Forest Research Station in Tanjung Puting National Park, Central Kalimantan, Indonesian Borneo. We want to encourage and help young Indonesian scientists and researchers.  Researchers in a boatYusi (at the front) and Harri (in the middle) conduting their research in Tanjung Puting National Park. Photograph by Brian MatthewsIn 2009, we provided two grants, one to Yusi Indriani for her research into the diversity of butterfly species around Pondok Ambung and one to Harri Purnomo for his research into the diversity of bird species. The students spent two months at Pondok Ambung conducting their research. Indonesian researcherYusi Indriani (in the middle) presenting her research results to Ashley Leiman (left), the Orangutan Foundation Director, Rene Bonke (right), a German Tomistoma researcher and Hudi DW (just left of centre), the Orangutan Foundation Programme Coordinator in Orangutan Foundation Pangkalan Bun office.butterfly at Tanjung Puting National ParkYusi recorded over 80 butterfly species. Orangutan FoundationI hope to bring you more news about Pondok Ambung and its amazing wildlife soon.Thank you,Hudi W.D.Orangutan Foundation Programme Co-ordinator

Add Power To Our Research

Pondok Ambung, our research station in Tanjung Puting National Park, has been mentioned quite a bit in my blog. In the late 80’s, Pondok Ambung was established as a proboscis monkey research site but by the end of 90’s it had been badly damaged by illegal loggers. The Orangutan Foundation’s team of volunteers repaired the site in 2001 but it remained abandoned until 2005 when the Rufford Maurice Laing Foundation awarded us a grant for its complete renovation.

Pondok Ambung Tropical Forest Research Station

And this is what we did.

The station requires a new solar power set. Solar is the only source of power providing electricity for the station. A new solar set costs $600 and any donations towards this amount would be hugely appreciated. So far the running and maintenance of the station has been entirely funded by the Foundation or from fees received from researchers staying at Pondok Ambung.

Solar power set
Recently, Pondok Ambung was used as the base for the “Orang-utan ‘08” expedition from the University of Aberdeen, Scotland. A team of four undergraduates led by Graham Banes spent eight weeks in Tanjung Puting studying the effects of disturbance, particularly forest fires, on the distribution and density of orangutans. Encouraging scientific research in Tanjung Puting National Park creates the knock on effect of increasing support for its protection.

Here are some of the incredible species that have drawn researchers to Pondok Ambung so far.

Tomistoma 2.jpg

Malaysian False Gharial (Tomistoma schlegelii)

Proboscis Monkey -photo by Dr Mark Fellowes

Proboscis Monkey



Pitcher Plant

Tropical Pitcher Plant

Adult Male Orangutan

And of course…Orangutans!

Thanks for your comments on my last post – I’ve just about recovered!

A very rare crocodile

Compared with the week before, when I spent four days out of six in the field, this week seems to have been very office bound with only one visit to the Orangutan Care Centre. I guess that is what happens as audit-time approaches. One exciting thing did happened. Rene Bonke, a German PhD student arrived to begin research into the ecology of the Malaysian False Gharial (Tomistoma schlegelii), one of the world’s rarest crocodiles.


Malaysian False Gharial (Tomistoma schlegelii)

Rene will be spending the next three months at Pondok Ambung Research Station in Tanjung Puting National Park (TPNP). Earlier studies, on which we also collaborated, found “the highest ever recorded density of wild Tomistoma” on the river system leading to Pondok Ambung and Camp Leakey.

Tomistoma are easily distinguished from the other species of crocodile found locally, the saltwater or estuarine crocodile (Crocodylus porosus).

Saltwater Crocodile

Saltwater Crocodile 2

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