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It's estimated that 2,000-3,000 orangutans are lost every year

Orangutans spend most of their time in trees.

“Orangutan" comes from the Malay words "orang" (person) and "hutan" (of the forest).

Orangutans exist in the wild only on the islands of Borneo and Sumatra.

Orangutans are classified as “critically endangered.”

Orangutans are extremely intelligent and make their own tools.

10th OC/OVAG Veterinary Workshop Announced

Displaced orangutans are being rescued nearly every day

Orangutans could be the first great ape to become extinct.

Orangutan rescue centers are at near full capacity in 2018

Archive for ‘From The Forest’

From the Forest: Aerial Flights Survey Orangutans – The Conservation Drone Project

From the Forest: Aerial Flights Survey Orangutans – The Conservation Drone Project

by Dr. Serge Wich and Dr. Lian Pin Koh

The authors arrive with their drone aircraft

This was our second trip to Aras Napal, Sumatra.

We were here several months earlier test-flying a prototype model of our Conservation Drones. Those initial test-flights were wildly successful in terms of obtaining video and photographic images of orangutans and elephants, as well as land use activities such as logging, fires, and oil palm expansion.

Drone's fly over of palm oil plantation








What we failed to capture were photographs of orangutan nests. This came as no surprise as orangutan nests are hard to detect in the thick closed-canopy rainforests of Sumatra, even from helicopter and small-aircraft surveys. But we were so convinced that Conservation Drones can spot these nests that we came back to the forest for another shot.

This was the third day we were out in an open field adjacent to the rainforest, but we saw no orangutan nests… yet.

We went through the usual pre-flight checks for the next mission, as our faces dripped with sweat from standing in the scorching sun. This was a 10-minute mission over a pre- programmed grid above the last large remaining lowland rainforest in the eastern part of the 2.5 million hectare Leuser Ecosystem: an amazing stretch of rainforest and one of the last strongholds of Sumatran tigers, orangutans and elephants.

The Leuser area stretches two provinces and is important for biodiversity conservation, while at the same time providing a multitude of ecosystem services for the people living around these forests and beyond.

At the flick of a switch on the radio transmitter and a gentle toss, the Conservation Drone took off into the wind.

Serge Wich sends drone on its mission

The 10-minute wait provided a much needed respite from the sun. We sat down in the shade and discussed how the flight parameters would need to be fine-tuned if this flight did not provide us with photographs of orangutan nests.

It is always exhilarating to be waiting for the Conservation Drone to return with the next stash of high-resolution photographs or video.
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posted by: Raffaella Commitante


From the Forest

From the Forest: Orangutan Research and Conservation in Sabangau – The Work of OuTrop


Mark E. Harrison

I became interested in primates at an early age, when I would watch endless natural history documentaries, climbed every tree in sight and even dreamed that, with appropriate surgery, I might be able to live a life in the trees like our primate cousins. Of course, I realize now that this last ambition may have been a little unrealistic, so have instead diverted my attention toward studying and helping to conserve these wonderful animals.

My optimism about working with primates dwindled during the final years of my undergraduate degree, however, as I discovered how difficult it was to get started in this field of work. This changed during a trip to Tanzania. I was travelling alone and went to visit Gombe National Park, which is world famous for the work of Jane Goodall, who was my greatest inspiration during my youth, and its chimpanzees.

Full of excitement, I set foot on the beach at Gombe and went to the national park office to pay my entrance fees, only to find that all of my money and travellers cheques had been stolen on the boat trip over! After making it this far, and meeting other visitors who had seen the chimpanzees, I was absolutely devastated. I never made it back to Gombe, but I resolved there and then that this would not be the end of my “ape experience,” and that I would do all I could to fulfil my (more realistic) childhood dreams.

Fortunately, not long after this in 2003, Helen Morrogh-Bernard offered me a position as her assistant on an orangutan behavior research project that she was establishing in the Sabangau Forest, Borneo, with the Orangutan Tropical Peatland Project (OuTrop).

OuTrop was established in 1999 on the back of Helen and Simon Husson’s undergraduate dissertation research, which was conducted in 1995 as part of a University of Nottingham and Leicester research expedition. Using newly-developed techniques for estimating orangutan population density, they discovered that Sabangau was home to the world’s largest orangutan population.

Simon and Helen have since been joined by many more researchers, including Laura D’Arcy and Dr Susan Cheyne and Dave Ehlers Smith. OuTrop’s remit has grown substantially as a result. We now conduct research into the area’s gibbons, red langurs and cats, plus a number of taxa included within our Ecological Monitoring Project, ranging from trees, to birds, ants and butterflies. Despite this diversification, our core mission has remained the same: to protect Kalimantan’s rich biodiversity through research, training and conservation, particularly within Sabangau.

The OuTrop Team 2012

The Sabangau Forest

Sabangau is one of the best and, at the same time, one of the worst places that I have ever visited. Its biodiversity is staggering: OuTrop and our collaborators have recorded 68 mammal, 167 bird and 218 tree species in the area. At 6,000 km2, Sabangau is also massive, and OuTrop’s surveys have revealed that it is home to the world’s largest population of orangutans (currently estimated at 6,900 individuals) and southern Bornean gibbons. It also contains important populations of many other threatened species. This makes it a very interesting forest in which to do research, and a very important one to understand and protect.
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posted by: Raffaella Commitante


From the Forest

From the Forest:  The Challenge of Research in Mawas 


Erin Vogel

Unlike my amazing colleagues who have spent decades studying orangutans and their conservation, I am a relative newcomer to the field. I am a trained ecologist interested in questions revolving upon the mechanisms animals use to obtain and utilize the energy that is necessary for survival.

Upon completing my Ph.D. in Ecology and Evolution, I was fortunate enough to have the opportunity to work with Dr. Carel van Schaik and Dr. Maria van Noordwijk, two primatologists who have dedicated their careers to exploring orangutan behavior and conservation. I’d spent my prior years studying dietary ecology of capuchin monkeys in Costa Rica, so the transition from a relatively easy field site in Costa Rica to the lowland peat-swamps of Central Kalimantan, Indonesia was exciting, yet shocking at the same time.

I began my journey studying orangutans in 2005 at the Tuanan Orangutan Research Station as part of the Tuanan Orangutan Research Project (TORP). This station was started in 2003 to deepen the  understanding of the effects of habitat degradation on orangutan behavior and to increase knowledge of orangutan behavior in general.

The Tuanan Orangutan Research Station was established as a joint effort between Dr. Carel P. van Schaik (Duke University / University of Zurich), Dr. Suci Utami Atmoko and Drs. Tatang MitraSetia of the Universitas Nasional Jakarta and the Borneo Orangutan Survival Foundation (BOSF) Mawas Program.

The Tuanan area in Central Kalimantan

You may ask – why is this field site important? Why should we focus our efforts on a selectively logged, peat-swamp forest?

Initial surveys within Mawas indicated a relatively high density of orangutans. A more formal survey later confirmed orangutan density around the Tuanan research area of between 3.84 and 4.71 individuals/km2, a figure well above densities reported from other field stations in Central Kalimantan. For example, orangutan density estimated at Sebangau National Park, located approximately 70 km from Mawas, is reportedly 1.82 individuals/km2.

In this essay, I discuss why these sites are important for conservation efforts, some of our research discoveries at Tuanan, and our recently established environmental education programs at schools surrounding the research area.

The Mawas Area

For the last few decades, preferred habitats of wild orangutans – the alluvial plains along major rivers and peat swamps – have been substantially reduced as a result of human exploitation for agricultural mono-crops, specifically the establishment of oil palm plantations.  Unsustainable land use practices have resulted in the fragmentation of unprotected orangutan habitats and have led to fatal consequences for orangutans..

Deforestation rates continue unabated in unprotected areas of Kalimantan and are currently estimated to be  above 1.5-2% per year.  Experts predict that without intervention and strong policies to prevent further deforestation, orangutans could potentially become extinct from the wild within a few decades.

It’s well known that the peat-swamp habitats preferred by orangutans are also major sources of carbon storage.  The soil carbon content found in peatlands globally is estimated at slightly less than all the carbon that exists in our atmosphere today. Given that 60% of all peatlands are found in Indonesia and a large majority of those are  in Kalimantan, it is naturally an important area to focus conservation efforts.
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posted by: Raffaella Commitante


From the Forest

 From the Forest:

Chasing Orangutans in Hutan Lindung Wehea, East Kalimantan, Indonesia


Roberto A. Delgado Jr.

I first went looking for free-ranging orangutans in earnest at Wehea forest during the summer of 2007. I’d previously conducted field research on orangutan behavioral ecology in northern Sumatra and West Kalimantan for my dissertation before being lured to the easternmost extent of their geographic range by the promise of studying an endangered and relatively poorly-known subspecies, the Northeast Bornean orangutan (Pongo pygmaeus morio).

At the time, “morio” was thought to occur at moderately high population levels. This subspecies holds particular interest to some researchers such as myself because it is reported as having the smallest cranial capacity, the most robust jaw morphology, and an accelerated life history pattern. That is, although some Sumatran orangutan populations are known as having the longest inter-birth interval among primates, reaching up to nine years, females from this Bornean subspecies are thought to give birth approximately every six years. Such drastic variation within closely related species often implies meaningful selection pressures most likely based on important environmental factors. The availability of resources and, specifically, both the spatio-temporal distribution and relative abundance of food patches, tend to be the usual suspects.

There is now increasing evidence that the lowland forests of East Kalimantan, Indonesia, are of poorer quality and less productive than other habitats within the geographic range of orangutans. These findings further suggest that, compared to other orangutan populations, preferred foods are scarce and unpredictable in their availability; thus, this subspecies must cope with a different set of ecological challenges than their counterparts elsewhere. Accordingly, this subspecies smaller brains and larger teeth would appear consistent with a strategy that minimizes energy expenditure in a harsh, resource-scarce environment (see From the Forest, October 2011).

A reasonable scenario to explain such traits is one that, for this population, would speed up development and other life history variables in light of uncertain habitat productivity while constraining cranial capacity under limited energy and nutrient supplies, but at the same time, enhancing dental features to exploit available food resources. With the idea of examining these intriguing questions, and also falling within my interest in geographic variation in behavior, I ventured to the forests of eastern Borneo.

Wehea base camp

Before my arrival, a number of Indonesian and western colleagues had paved the way. Specifically, scientists from the Tropical Forest Research Center at Mulawarman University in Samarinda had identified several forest sites as having good orangutan habitat.  In addition, field teams from The Nature Conservancy (TNC) had estimated relatively high local population densities based on indirect nest surveys throughout a subset of forest tracts in East Kalimantan. In fact, two sites had been selected initially for further monitoring and biodiversity research, one of which was Wehea.
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posted by: Raffaella Commitante