Protecting proboscis monkeys from deforestation

By: Thomas Schmitt Attorney on January 03, 2019 / comment : 0 Borneo, Ecosystems, Endangered Species, Natural Heritage, Wildlife

A 10-year study of proboscis monkeys in Borneo has revealed that forest conversion to oil palm plantations is having a significant impact on the species.

Credit: Cardiff University

Nearly half of all primate species are threatened with extinction, with habitat destruction acting as the key driving force. New research studied proboscis monkeys from 2004 to 2014, finding that the protection of swamp forests is vital for their survival.

The study led by Cardiff University, Chubu University, Hokaido University, Sun Yat-sen University, Living Landscape Alliance, the NGO HUTAN, Sabah Wildlife Department and Danau Girang Field Centre, tracked changes in population sizes over a decade, revealing significantly reduced sizes of proboscis monkey groups.

Dr. Benoit Goossens, Director of Danau Girang Field Centre and Reader at Cardiff University School of Biosciences, said: "We compared population sizes from 2004 and 2014, and it revealed subtle changes, where population densities fluctuated but had neither increased nor decreased. But importantly, we discovered that the sizes of the groups were significantly reduced.

Mr Augustine Tuuga, Director of Sabah Wildlife Department, said: "Proboscis monkeys are endemic to the island of Borneo. They are classified as endangered and are also a Totally Protected species in Sabah. Despite these levels of protection, lowland swamp forest habitats that are important for this species are still decreasing, mainly through forest conversion to oil palm plantations.

"Our analysis of the habitat changes showed that within protected reserves, there was relatively little forest loss in the potential range of the proboscis monkey, which mainly lies 800m from riverbanks."

"This suggests that the protection of swamp forests can contribute immensely to the sustainability of proboscis monkeys within these important habitats. However, larger losses of interior forests meant that habitats had generally become more degraded and fragmented, and this could have contributed to reduced group sizes and limited population growth," added Dr. Marc Ancrenaz, Scientific Director at the NGO HUTAN.

Dr. Benoit Goossens concluded: "Although the protection of forests within the proboscis monkeys' range had proved effective, this was not the case in unprotected forests, where 12 percent of the forest was lost and could eventually lead to 23 percent of the population being threatened.

"At least a third of these forests has been allocated for oil palm cultivation. Further efforts must be undertaken to more effectively conserve high value habitats and to restore swamp forest areas – this is vital for ensuring the survival of this endangered species."

Source: Cardiff University [January 03, 2019]

Re-inventing the hook: Orangutans spontaneously bend straight wires into hooks to fish for food

By: Thomas Schmitt Attorney on November 09, 2018 / comment : 0 Borneo, Endangered Species, Indonesia, Natural Heritage, Psychology, Sumatra, Wildlife

The bending of a hook into wire to fish for the handle of a basket is surprisingly challenging for young children under eight years of age. Now cognitive biologists and comparative psychologists from the University of Vienna, the University of St Andrews and the University of Veterinary Medicine Vienna around Isabelle Laumer and Alice Auersperg studied hook tool making for the first time in a non-human primate species - the orangutan. To the researchers' surprise the apes spontaneously manufactured hook tools out of straight wire within the very first trial and in a second task unbent curved wire to make a straight tool.

Wild male orangutan [Credit: © Graham L. Banes]

Human children are already proficient tool-users and tool-makers from an early age on. Nevertheless, when confronted with a task, which required them to innovate a hooked tool out of a straight piece of wire in order to retrieve a basket from the bottom of a vertical tube, the job proved more challenging for children than one might think: Three to five-year-old children rarely succeed and even at the age of seven less than half of them were able to solve the task. Only at the age of eight the majority of children was able to innovate a hook-tool. Interestingly children of all tested age classes succeeded when given demonstrations on how to bend a hook and use it. Thus, although young children apparently understand what kind of tool is required and are skilled enough to make a functional tool, there seems to be a cognitive obstacle in innovating one.

Cognitive biologists and comparative psychologists from the University of Vienna, the University of St Andrews and the University of Veterinary Medicine in Vienna around Isabelle Laumer now tested for the first time a primate species in the hook-bending task. "We confronted the orangutans with a vertical tube containing a reward basket with a handle and a straight piece of wire. In a second task with a horizontal tube containing a reward at its centre and a piece of wire that was bent at 90°", explains Isabelle Laumer who conducted the study at the Zoo Leipzig in Germany. "Retrieving the reward from the vertical tube thus required the orangutans to bent a hook into the wire to fish the basket out of the tube. The horizontal tube in turn required the apes to unbent the bent piece of wire in order to make it long enough to push the food out of the tube."

Male orangutan using a stick tool [Credit: © Alice Auersperg]

Several orangutans mastered the hook bending task and the unbending task. Two orangutans even solved both tasks within the first minutes of the very first trial. "The orangutans mostly bent the hooks directly with their teeth and mouth while keeping the rest of the tool straight. Thereafter they immediately inserted it in correct orientation, hooked the handle and pulled the basket up", she further explains.

Orangutans share 97% of their DNA with us and are among the most intelligent primates. They have human-like long-term memory, routinely use a variety of sophisticated tools in the wild and construct elaborate sleeping nests each night from foliage and branches. Today orangutans can only be found in the rainforests of Sumatra and Borneo. Like all four great ape species, orangutans are listed as critically endangered (IUCN, Red List). "Habitat loss due to extensive palm-oil production, illegal wildlife trade and poaching are the major threats. Palm oil is the most widely used vegetable oil in the world. As long as there is a demand for palm oil and consumers keep buying products that contain palm oil, the palm industry thrives. According to a 2007 survey by the United Nations Environment Program (UNEP) orangutans will be extinct in the wild within two decades if current deforestation trends continue", says Isabelle Laumer.

Orangutans in the wild [Credit: © Graham L. Banes]

"The hook-bending task has become a benchmark paradim to test tool innovation abilities in comparative psychology", says Alice Auersperg from the University of Veterinary Medicine in Vienna. "Considering the speed of their hook innovation, it seems that they actively invented a solution to this problem rather than applying routined behaviours."

"Finding this capacity in one of our closest relatives is astonishing. In human evolution hook tools appear relatively late. Fish hooks and harpoon-like, curved objects date back only approximately 16.000- 60.000 years. Although New Caledonian crows use hooks with regularity, there are a few observations of wild apes, such as chimpanzees and orangutans, that use previously detached branches to catch and retrieve out-of-reach branches for locomotion in the canopy. This branch-hauling tools might represents one of the earliest and simplest raking tools used and made by great apes and our ancestors", says Josep Call of the University of St Andrews.

So why struggle younger children with this task? "Follow-up studies showed that childrens difficulty with independently finding the solution cannot be explained by fixedness on unmodified tools, impulsivity nor by not being able to change the strategy. The hook bending task represents a complex problem, for which several unrewarded steps must be performed while keeping the final goal in mind", explains Isabelle Laumer. "Interestingly, complex problem solving has been associated to certain areas of the medial prefrontal cortex, which mature later in the child development. This explanation, besides children´s strong reliance on social learning might explain their success at a later age."

The study is published in Scientific Reports.

Source: University of Vienna [November 09, 2018]

Oldest known figurative cave art discovered in Borneo

By: Thomas Schmitt Attorney on November 07, 2018 / comment : 0 Archaeology, Asia, Borneo, Indonesia, South East Asia

Griffith University researchers have dated cave paintings in Borneo to as early as 40,000 years ago, showing that these enigmatic artworks are among the world’s oldest examples of figurative depiction.

Composition of mulberry-coloured hand stencils superimposed over older reddish/orange hand stencils.  The two styles are separated in time by at least 20,000 years [Credit: Kinez Riza]

This finding adds to the mounting view that cave art – one of the most important innovations in human cultural history – did not arise in Europe as long believed, and that ‘ice age’ artists in Southeast Asia played a key role in its development.

Since the 1990s, caves in remote and rugged mountains of East Kalimantan, an Indonesian province of Borneo, have been known to contain prehistoric paintings, drawings, and other imagery, including thousands of depictions of human hands (“stencils”), animals, abstract signs and symbols, and related motifs.

These near-inaccessible artworks are now known to be far older than previously thought, according to a study led by Griffith’s Associate Professor Maxime Aubert, along with Indonesia’s National Research Centre for Archaeology (ARKENAS), and the Bandung Institute of Technology (ITB), published in Nature.

Composition of mulberry-coloured hand stencils from East Kalimantan, Indonesian Borneo.  This particular style of hand stencil dates to the height of the Last Glacial Maximum  about 20,000 years ago [Credit: Kinez Riza]

Associate Professor Aubert’s team reports Uranium-series dates obtained from calcium carbonate samples collected from the Kalimantan cave art, providing the first reliable estimates for the approximate time of rock art production.

“The oldest cave art image we dated is a large painting of an unidentified animal, probably a species of wild cattle still found in the jungles of Borneo – this has a minimum age of around 40,000 years and is now the earliest known figurative artwork,” Associate Professor Aubert said.

The Kalimantan stencil art was shown to be similar in age, suggesting that a Palaeolithic rock art tradition first appeared on Borneo between about 52,000 and 40,000 years ago.


Dating also indicated that a major change occurred within this culture around 20,000 years ago, giving rise to a new rock art style (including rare portrayals of humans) at a time when the global ice age climate was at its most extreme.

“Who the ice age artists of Borneo were and what happened to them is a mystery,” said team co-leader Dr Pindi Setiawan, an Indonesian archaeologist and lecturer at ITB. Setiawan has studied the art since its discovery, and, along with ARKENAS rock art expert Adhi Agus Oktaviana, leads expeditions to the Kalimantan caves.

“The new findings illustrate that the story of how cave art emerged is complex,” Oktaviana said.

Human figures from East Kalimantan, Indonesian Borneo. This style is dated to at least 13,600 years ago  but could possibly date to the height of the last Glacial Maximum 20,000 years ago  [Credit: Pindi Setiawan]

Europe has long been seen as the centre for cave art development. But although Borneo is the Earth’s third largest island, throughout most of the ice age it actually formed the easternmost tip of the vast continental region of Eurasia – at the western extremity of this 13,000 km-wide landmass was Europe.

“It now seems that two early cave art provinces arose at a similar time in remote corners of Palaeolithic Eurasia: one in Europe, and one in Indonesia at the opposite end of this ice age world,” said Associate Professor Adam Brumm, a Griffith archaeologist also involved in the study.

A 2014 Nature paper published by Associate Professors Aubert and Brumm (with ARKENAS) revealed that similar cave art appeared in the island of Sulawesi about 40,000 years ago.

The worlds oldest figurative artwork from Borneo dated to a minimum of 40,000 years  [Credit: Luc-Henri Fage]

Sulawesi lies off the edge of Eurasia and is a vital stepping-stone between Asia and Australia.

“Our research suggests that rock art spread from Borneo into Sulawesi and other new worlds beyond Eurasia, perhaps arriving with the first people to colonise Australia,” Associate Professor Aubert said.

Read The Conversation article

Source: Griffith University [November 07, 2018]

Land-based bird populations are at risk of local extinction

By: Thomas Schmitt Attorney on September 21, 2018 / comment : 0 Bali, Biodiversity, Borneo, Endangered Species, Java, Natural Heritage, South East Asia, Sumatra, Thailand, Wildlife

Land-based bird populations are becoming confined to nature reserves in some parts of the world -- raising the risk of global extinction -- due to the loss of suitable habitat, according to a report led by UCL.

Credit: University College London

Researchers analysed biodiversity in the area known as Sundaland, which covers the peninsula of Thailand, Borneo, Malaysia, Sumatra, Java and Bali, one of the world's most biologically degraded regions.

The study, published in Conservation Letters, focuses on galliformes -- heavy-bodied ground-feeding birds such as pheasants, grouse and quail -- as their numbers are well-recorded and they are amongst the most threatened species in some parts of the world.

Scientists found that up to 13 populations (25 per cent of galliform populations in the area) have been extirpated (made locally extinct) in the region and no longer exist outside nature reserves (protected areas). The island of Sumatra has suffered the highest proportion of extirpations among the areas studied, having lost 50 percent of its galliform species in unprotected land.

As a result, certain species are only found in protected areas -- raising questions about the ultimate goal of conservation. The researchers argue that these areas were never intended to be a last resort for the existence of species and are also coming under increasing threat from human activity.

Professor Elizabeth Boakes (UCL Life Sciences) said: "Land outside of protected areas is increasingly being lost to agriculture and infrastructure, leading to species becoming confined to Sundaland's protected areas. Biodiversity in the unprotected landscape is required to maintain connectivity and ecosystem function.

"It is also critical that protected areas are managed effectively. However, nearly 20 per cent of Malaysia's and over 40 per cent of Indonesia's protected land is subject to intense human pressure.

"As one of the most biologically degraded areas, Sundaland offers a stark warning to the rest of the world should global rates of land conversion continue unabated. Conservation's end goal is not islands of biodiversity, marooned in a sea of destruction. More land must be managed in a way that accommodates biodiversity for the long term."

Sundaland is a biological hotspot, meaning it is rich in biodiversity but at risk of destruction. Despite the existence of protected areas, forest cover in Sumatra declined by five per cent between 1990 and 2000, while Kalimantan's protected lowland forests declined by more than 56 per cent between 1985 and 2001.

In addition to this, protected areas are not necessarily permanent, with downgrading over the last few years equating to a loss of 8360km² of protected land. As they become more isolated in agricultural landscapes or by the spread of roads and other infrastructure, species lose the opportunity to track and adapt to climate change.

An example of this is that just 12 per cent of Borneo's protected areas are topographically diverse enough to allow species to survive a high warming scenario.

Dr Philip McGowan, Newcastle University School of Natural and Environmental Sciences and Chair of IUCN Species Survival Commission Task Force on post 2020 biodiversity targets said: "These findings present new insights into how we should view protected areas and their ability to conserve species across landscapes.

"At a time when there is debate about how much land should be given over to protected areas, it is how they are integrated into global biodiversity targets that is perhaps critical. These targets are currently being reviewed by the Convention on Biological Diversity, which is also discussing what should follow them when they expire in 2020."

Southeast Asia's deforestation rate is the highest among tropical regions, above five per cent annually in parts of Sumatra and Sarawak. Sundaland's lowland forests are rapidly disappearing, giving us an insight into the future global conservation status of the remainder of the world if land outside of protected areas continues to be lost, putting the reserves at increased risk from climate change and human activity.

Source: University College London [September 21, 2018]

Rethinking the orangutan: How 70,000 years of human interaction have shaped an icon of wild nature

By: Thomas Schmitt Attorney on June 27, 2018 / comment : 0 Borneo, Endangered Species, Fossils, Indonesia, Natural Heritage, Sumatra, Wildlife

The evolution of the orangutan has been more heavily influenced by humans than was previously thought, new research reveals.

Orangutan are living in heavily disturbed landscape dominated by oil palm plantations in the Lower Kinabatangan floodplain, Malaysian Borneo [Credit: HUTAN/KOCP (Kinabatangan Orang-utan Conservation Programme)]

Professor Mike Bruford, of Cardiff University, was part of the team of scientists shedding light on the development of the critically endangered species. Their findings offer new possibilities for orangutan conservation.

One of humans' closet living relatives, the orangutan has become a symbol of nature's vulnerability in the face of human actions and an icon of rainforest conservation.

But in the research paper published in the journal Science Advances, the team argues this view overlooks how humans, over thousands of years, have shaped the orangutan known today.

Professor Bruford, of the Sustainable Places Research Institute and the School of Biosciences who is a co-author of the paper, said: "This research offers new hope for how we can save the orangutan from extinction.

"Our studies show that orangutans actually have a long history of adapting their behaviour to survive in different areas, even those that have been heavily impacted by humans. This means they can live in much more varied habitats than previously thought.

"There needs to be a multifaceted approach to conservation efforts that incorporates human-dominated landscapes, reduces hunting and increases habitat quality."

This is an orangutan fossil tooth from the Pleistocene in Sumatra [Credit: Gilbert Price]

It was often assumed that environmental factors like fruit availability were primarily responsible for most features of modern-day orangutans, such as the fact that they usually live at low densities and have a restricted geographic distribution.

But the study indicates the orangutan that existed before modern humans and arrived in Southeast Asia 70,000 years ago may have been quite different.

Lead author Stephanie Spehar, an associate professor of anthropology at the University of Wisconsin Oshkosh, said: "Our synthesis of fossil, archeological, genetic and behavioral evidence indicates that long-term interactions with humans shaped orangutans in some pretty profound ways."

These creatures were once far more widespread and abundant, with orangutan teeth among the most common animal remains in deposits in China, Thailand and Vietnam. They weathered many environmental changes and may even have lived in a wider range of environments than their modern counterparts.

Today, the orangutan is only found on the islands of Borneo and Sumatra.

Studies of the species living in heavily human-impacted habitats, such as oil palm and forestry plantations, highlight that the apes can adapt to survive in such areas, at least in the short term.

It had always been assumed that orangutans were mostly arboreal, but camera traps in the forest showed they also walk extensively on the ground in some areas. The team is calling for these findings to be applied to conservation efforts immediately.

Professor Bruford added: "Although much effort has already been made to understand the endangered orangutan, this latest study shows that much work still needs to be done to ensure conservation strategies are as robust and wide-ranging as possible. Only then will we stand a fighting chance of preventing this incredibly important animal from being wiped out."

Source: Cardiff University [June 27, 2018]

Late Pleistocene human mandibles from Borneo's Niah Caves may hint at ancient diets

By: Thomas Schmitt Attorney on June 06, 2018 / comment : 0 Anthropology, Borneo, Forensics

Three human mandibles may provide new insight into the diet of Late Pleistocene hunter-gatherers in Borneo, according to a study published in the open-access journal PLOS ONE by Darren Curnoe from the University of New South Wales, Australia, and colleagues.

Niah Caves archaeological site where the mandibles were found [Credit: Darren Curnoe]

Little is known about the early hunter-gatherer populations that lived in island Southeast Asia since human remains from the Late Pleistocene-early Holocene era are extremely rare. The Niah Caves in the northeast of Borneo have been identified as a promising archaeological site for learning about the early humans that dwelled in this region.

Curnoe and colleagues examined three human mandibles that were previously excavated from the West Mouth of the Niah Cave in 1957. Using Uranium-series dating techniques, the researchers estimate that one of the mandibles is 28-30,000 years old, while the other two are at least 11,000 and 10,000 years old, respectively. The oldest mandible of the three was smaller and more robust compared to other Late Pleistocene mandibles, and this may suggest that it was subject to strain that could have been caused by consuming tough or dried meats or palm plants, a diet that has previously been identified in the Niah Caves.

Two human jaws from Niah Caves in Borneo found in 1958 but only just revealed. Top jaw is 30,000 years old, bottom jaw 11,000 years old [Credit: Darren Curnoe]

The researchers suggest that their study helps provide insight into the diet of ancient people living near tropical rainforests, a region which has been previously identified as facing economic difficulties. Through their potential consumption of raw plant foods and dried meats, the hunter-gatherer populations living in this region around the Late Pleistocene may have been adapting to their economically challenging environment.

"These early modern humans were seemingly adapted to a difficult life in the tropical rainforests with their very small bodies and ruggedly build jaws from chewing really tough foods," says Curnoe. "They tell us a lot about the challenges faced by the earliest people living in island Southeast Asia."

Source: Public Library of Science [June 06, 2018]