Orangutans weren't always found at such low densities, unsurprisingly, humans to blame

From National Geographic blogs
Hunting a key factor in orangutan's decline, study suggests
by RICHARD THOMAS

Humans entering the forests of Borneo 150 years ago were six times more likely to encounter wild orangutans than they would today, a new study finds. The researchers suspect that heavy hunting over the years is to blame. The finding means our understanding of the lives and behaviors of the great ape is based on artificially low population densities. We may need to rethink what we know about our nearest animal relative.

Hunting appears to have been significantly underestimated as a key reason for the historical decline of orangutans, according to a new study published today.

An international team of scientists noted how animal collectors operating in the mid-19th Century in Borneo [an island shared by Indonesia and Malaysia] were able to shoot orangutans on a daily basis and speculated that 150 years ago, encounter rates with the forest primates must have been far higher than they are today.

To test the hypothesis, the researchers attempted to quantify historic encounter rates from information contained in hunting accounts and museum collections and comparing them to recent field studies.

"Even after allowing for variations in the size and length of hunting and survey expeditions and other variables, we estimated that daily encounter rates with orangutans have declined by about six-fold in areas with little or no forest disturbance," said Erik Meijaard, of People and Nature Consulting International in Indonesia, the lead author of the study.

Possible explanations for the decline were examined, including habitat loss and degradation, hunting, disease, and even changes in behavior, such as animals becoming more wary in the face of human persecution.

"Although there are gaps in the data, after examining several possible explanations, we concluded that high levels of hunting was the most likely cause of the reduced encounter rates over time," said Vincent Nijman, of Oxford Brookes University, a co-author of the study.

Despite legal protection, hunting of orangutans still occurs and may have had a more significant impact on wild populations than previously realized.

According to Meijaard, recent unpublished studies in Indonesian Borneo suggest that more than 1,000 orangutans are killed annually.

Orangutans are hunted for a variety of reasons, including food, as agricultural pests, and to obtain young individuals for the pet trade.

Hanging in the balance, an assessment of trade in gibbons and orangutan in Kalimantan, Indonesia, a TRAFFIC report published in 2005, found that the vast majority of orangutans in trade were young animals, suggesting that the adult females had been hunted.

"We need to understand better how orangutan populations are affected by different levels of hunting pressure," said Nijman.

"Indeed, our findings may force us to rethink the whole biology of orangutans. Much of our current ecological understanding is possibly based on field studies of animals living at densities below those that would be imposed by food availability."

"How would the species behave if natural densities were 5 or 10 times higher than those we currently observe?"

Declining orangutan encounter rates from Wallace to the present suggest the species was once more abundant by Erik Meijaard, Alan Welsh, Marc Ancrenaz, Serge Wich, Vincent Nijman and Andrew J. Marshall, is available from PLoS One.

Richard Thomas is the communications coordinator for TRAFFIC, the UK-based wildlife trade monotiring network. This article is reproduced on Nat Geo News Watch courtesy of TRAFFIC.

The views expressed here are those of Richard Thomas or TRAFFIC and not necessarily those of the National Geographic Society.

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REEFERNCE
Meijaard E, Welsh A, Ancrenaz M, Wich S, Nijman V, et al. (2010) Declining Orangutan Encounter Rates from Wallace to the Present Suggest the Species Was Once More Abundant. PLoS ONE 5(8): e12042. doi:10.1371/journal.pone.0012042

ABSTRACT
Background
Bornean orangutans (Pongo pygmaeus) currently occur at low densities and seeing a wild one is a rare event. Compared to present low encounter rates of orangutans, it is striking how many orangutan each day historic collectors like Alfred Russel Wallace were able to shoot continuously over weeks or even months. Does that indicate that some 150 years ago encounter rates with orangutans, or their densities, were higher than now?

Methodology/Principal Findings
We test this hypothesis by quantifying encounter rates obtained from hunting accounts, museum collections, and recent field studies, and analysing whether there is a declining trend over time. Logistic regression analyses of our data support such a decline on Borneo between the mid-19th century and the present. Even when controlled for variation in the size of survey and hunting teams and the durations of expeditions, mean daily encounter rates appear to have declined about 6-fold in areas with little or no forest disturbance.

Conclusions/Significance
This finding has potential consequences for our understanding of orangutans, because it suggests that Bornean orangutans once occurred at higher densities. We explore potential explanations—habitat loss and degradation, hunting, and disease—and conclude that hunting fits the observed patterns best. This suggests that hunting has been underestimated as a key causal factor of orangutan density and distribution, and that species population declines have been more severe than previously estimated based on habitat loss only. Our findings may require us to rethink the biology of orangutans, with much of our ecological understanding possibly being based on field studies of animals living at lower densities than they did historically. Our approach of quantifying species encounter rates from historic data demonstrates that this method can yield valuable information about the ecology and population density of species in the past, providing new insight into species' conservation needs.

Reintroduced orangs get microchipped

Orang utans get trackers 
Associated Press via straitstimes.com

KUALA LUMPUR - VETERINARIANS have been tracking three orang utans they implanted with tiny transmitters as part of efforts to protect the endangered primates once they reintroduce them to the wild, a Malaysian official said on Monday.

French and Austrian veterinarians worked with the Wildlife Department in eastern Sabah state on Borneo island to implant specially designed coin-sized transmitters in the necks of the orang utans for the first time ever in September, said Dr Senthilvel Nathan, the department's chief field veterinarian.

The orang utans' jungle habitat in Sabah has shrunk over the decades and their numbers have plummeted as loggers cut down the forests and plantation farming encroached.

Fewer than 11,000 orang utans remain in Sabah. Up to eight times that number existed 15 years ago, a French-based conservation group, Hutan, has estimated.

The three orang utans are among about 250 primates that were cared for by humans after being found sick, injured or orphaned when they were young. They now live in a 15 square-mile (40 sq.-kilometre) reserve that can only handle a limited number of them, Dr Senthilvel said.

The transmitters will not be able to show any imminent threat to the orang utans, but they will allow officials to monitor their whereabouts in the wild and find them quickly if necessary

Degraded Borneo land to be restored to orangutans

 image from replantingtherainforests.com  

Article from the WWF facebook page (original article on www.panda.org ) 

Kota Kinabalu, Sabah: Almost 1000 hectares of degraded land in the area designated Heart of Borneo is to be restored as orangutan habitat, following the signing of a memorandum of understanding between WWF-Malaysia and the State of Sabah yesterday.

The five year memorandum for the project - made possible with RM4.35 million ($US 1.27 million) grant from the ITOCHU Corporation of Japan - was signed during a regional forum on ‘Enhancing forest eco-systems and corridors within the Heart of Borneo

The 967 hectare area is in the North Ulu Segama landscape of Sabah, where some orang-utan populations had become isolated due to a combination of the natural barrier of the Ulu Segama River and logging and other activities.

Poor quality habitat is expected to lead to further organgutan population declines.

Opening the forum, Sabah Chief Minister Datuk Seri Musa Aman, said the State was very serious about conserving its forests and very committed to the Heart of Borneo, adding that 250,000 hectares of forest had already been set aside for conservation.

However, he said financing remained a crucial subject. To this end he thanked the Malaysian Federal government for its contribution of RM5 million ($US 1.47 million) to the Sabah Forestry Department to kick-start programme implementation - but indicated more help was needed.

“It is the hope of the Sabah state government that ‘friends’ from European countries and the USA can lend support to this endeavour,” he said.

WWF’s Heart of Borneo Initiative Leader, Adam Tomasek, congratulated the Sabah state government’s commitment to the Heart of Borneo and emphasised his gratitude to Japan’s ITOCHU Group for its generous contribution.

“These funds are vital for the restoration of a high priority landscape and long-term viability for orangutans. Healthy forest ecosystems are a priority for the three country Heart of Borneo initiative, and Sabah is providing a strong leadership example of working with the international community to realize this goal”

"ITOCHU's support is a clear sign of Japanese interest in the Heart of Borneo and as host of the 2010 UN Convention on Biological Diversity conference we look forward to profiling this growing partnership between governments and private sector," Mr Tomasek said.

Hidden colony of orang-utans is discovered in the forests of Borneo

Photo by Sara Hastings (Pandana of the Leipzig Zoo, Germany)

Article from the Independant
By Daniel Howden
Published: 03 December 2007

Conservationists working to combat deforestation on the island of Borneo have uncovered a "hidden colony" of 800 orang-utans in an area under imminent threat from the expansion of the palm oil industry.

The previously uncounted apes have been found in the Sungai Putri, a tract of rare peat swamp forest in the West Kalimantan province of Indonesian Borneo. But the area has recently been rezoned by local government and concessions for palm oil plantations could be sold at any time.

Frank Momberg, country director of the conservation group Flora and Fauna international, is part of a group of scientists and environmentalists who were studying the massive carbon deposits in the area when they came upon the colony. "Local people knew of course [that they were there]," he said. "But no scientist had ... recorded this population before."

Mr Momberg is leading an urgent effort to protect the 57,000-acre forest and guarantee a future for the orang-utans and other endangered species in Sungai Putri, as well as the millions of tons of carbon it secures.

Borneo is divided between Indonesia, Malaysia and Brunei, and is at the epicentre of deforestation worldwide. Half of all tropical timber used on the planet comes from this one island. Peat swamp forests like Sungai Putri are among the most important carbon sinks on the planet, yet vast areas of them have been drained in recent years for conversion to agricultural land, releasing millions of tons of CO2 into the atmosphere.

The swampy floor of Sungai Putri, thick with decaying trees and rich organic matter up to 11m deep in places, is not only a dense, deep carbon sink, says Mr Momberg, but the "most efficient terrestrial ecosystem for the sequestration of carbon".

Deforestation accounts for one-fifth of all carbon released into the atmosphere and Indonesia's slash and burn policies have already seen the country become the third-largest emitter of greenhouse gases.

It has also meant massive habitat loss for Asia's only great ape. The orang-utan could be the first great ape to be made extinct. The "man of the forest" used to be common throughout Asia but now survives only on the islands of Borneo and Sumatra. There are some 7,000 Sumatran orang-utans left and the estimated population of 40,000 remaining on Borneo is also in steep decline.

Delegates at the climate talks in Bali will be asked to radically expand the Kyoto Protocol which would see countries like Indonesia rewarded for avoiding further deforestation.

If the proposals, backed by scientists, environmentalists, developing nations and a growing business lobby, can be agreed, areas such as Sungai Putri could be worth millions of dollars and play a key role in combating climate change.

But the quick returns offered from palm oil mean the threat to the forest remains real and 70 per cent of Sungai Putri could be wiped out within five years.

"Farmers use fire to clear the land and fires are already burning at the edges," said Mr Momberg. "Illegal logging is ongoing with small scale but continuous degradation of the forest."

Help may be at hand from a new kind of conservation effort. A green investment company, Carbon Conservation, has been working with local communities, Flora and Fauna International and local government to bring in outside funding. They are setting up a scheme under which private-sector investors put in money which is used both to protect the forest and offer alternative incomes to local people. In return investors get carbon credits for the area which has avoided deforestation.

At the moment the market for the voluntary credits is small but that could change overnight if the UN talks deliver an international framework deal.

Dorjee Sun, the chief executive of Carbon Conservation, said that negotiations were well advanced. A leading investment bank and others were just waiting for a signal from Bali.

"The private sector is showing the way by buying voluntary credits, now it's over to the governments in Bali," he said. "It's time for them to just do it."