We have discovered a new species of orangutan – the third known species and the first new great ape to be described since the bonobo almost a century ago.
The new species, called the Tapanuli orangutan (Pongo tapanuliensis), has a smaller skull than the existing Bornean and Sumatran orangutans, but has larger canines.
As we and our colleagues report in the journal Current Biology, the new species is represented by an isolated population of fewer than 800 orangutans living at Batang Toru in northern Sumatra, Indonesia.
The existence of a group of orangutans in this region was first reported back in 1939. But the Batang Toru orangutans were not rediscovered until 1997, and then confirmed in 2003. We set about carrying out further research to see whether this isolated group of orangutans was truly a unique species.
On the basis of genetic evidence, we have concluded that they are indeed distinct from both the other two known species of orangutan: Pongo abelii from further north in Sumatra, and Pongo pygmaeus from Borneo.
The Batang Toru orangutans have a curious mix of features. Mature males have cheek flanges similar to those of Bornean orangutans, but their slender build is more akin to Sumatran orangutans.
The hair colour is more cinnamon than the Bornean species, and the Batang Toru population also makes longer calls than other orangutans.
To make completely sure, we needed more accurate comparisons of their body dimensions, or “morphology”. It was not until 2013 that the skeleton of an adult male became available, but since then one of us (Anton) has amassed some 500 skulls of the other two species, collected from 21 institutions, to allow for accurate comparisons.
Analyses have to be conducted at a similar developmental stage on male orangutan skulls, because they continue growing even when adult. Anton found 33 skulls of wild males that were suitable for comparison. Of 39 different measurement characteristics for the Batang Toru skull, 24 of them fall outside of the typical ranges of northern Sumatran and Bornean orangutans.
Overall the Batang Toru male has a smaller skull, but bigger canines. Combining the genetic, vocal, and morphological sources of evidence, we have confidently concluded that Batang Toru orangutan population is a newly discovered species – and one whose future is already under threat.
Despite the heavy exploitation of the surrounding areas (hunting, habitat
alteration and other illegal activities), the communities surrounding the habitat of the Tapanuli orangutan still give us the opportunity to see and census the surviving population. Unfortunately, we believe that the population is fewer than 800 individuals.
Of the habitat itself, no more than 10 square km remains. Future development has been planned for that area, and about 15% of the orangutans’ habitat has non-protected forest status.
The discovery of the third orangutan in the 21st century gives us an understanding that the great apes have more diversity than we know, making it all the more important to conserve these various groups.
Without the strong support of, and participation from, the communities surrounding its habitat, the future of the Tapanuli orangutan will be uncertain. Government, researchers and conservation institutions must make a strong collaborative effort to make sure that this third orangutan will survive long after its discovery.
But does that mean the threat of any eruption is over?
A few false starts
The last major eruption of Mount Agung was in 1963. Since then, there have been two known periods of activity at the volcano site without an ensuing eruption.
In 1989, a few volcanic earthquakes occurred and hot, sulphur-rich gas emissions were observed with no eruption.
Between 2007 to 2009, satellite data showed inflation (swelling) of the volcano at a rate of about 8cm per year, probably caused by the inflow of new magma (molten rock) into the shallow plumbing system. This was followed by deflation for the next two years, again without an eruption.
The current volcanic activity – mainly the number of earthquakes – has not subsided since the alert level was raised to level 4. It continues to fluctuate at high levels, with more than 600 earthquakes a day. This indicates that the threat of an eruption is still high, despite a general decline in overall seismic energy.
This past weekend saw the highest number of daily earthquakes, with more than 1,100 recorded on Saturday October 14.
The latest statement from the Indonesian Centre for Volcanology and Geological Hazard Mitigation was released on October 5. It said earthquake data indicates that pressure is continuing to build up under the volcano due to the increasing magma volume and as magma moves towards the surface.
It’s all about the gas
Magma contains dissolved gases (volatiles) such as water, carbon dioxide and sulphur dioxide. As magma moves towards the surface, the pressure becomes less and so gas bubbles form, akin to taking the top off a fizzy drink bottle. These gas bubbles take up additional space in the magma and increase the overall pressure of the system.
The amount of gas, and whether or not gas is able to escape from the magma prior to eruption, are major factors that determine how explosive (or not) any volcanic eruption will be.
If the gas bubbles forming in the magma stay within as it ascends beneath Mount Agung, then it could lead to a more explosive eruption. If the gas formed is able to escape, it might depressurise the system enough to erupt less violently or not at all.
White gas plumes, composed mainly of water vapour, have been observed. They have typically reached 50-200m above the crater rim at Mont Agung, and up to 1,500m on October 7. This water vapour is likely due to the hydrologic system heating up in response to the intruding magma at depth.
During the 1963 eruption, Mount Agung produced a significant amount of sulphur-rich gas that caused an estimated global cooling of 0.1-0.4℃. In this current phase of activity, we are yet to see any significant release of sulphur dioxide from the intruding magma.
How big would an eruption be?
It’s not easy to predict how big any eruption at Mount Agung would be. Analysis of volcanic material deposited during previous eruptions over the past 5,000 years suggests that about 25% of them have been of similar or larger size than the 1963 eruption.
In 2010, the Indonesian Center of Volcanology and Geological Hazard Mitigation issued timely forecasts of the size of the eruption phases at Merapi, saving an estimated 10,000–20,000 lives.
The waiting game
The Indonesians are keeping a close eye on seismic activity at Mount Agung and the public can watch a live seismogram.
The last two eruptions of Mount Agung in 1843 and 1963 had a Volcanic Explosivity Index (VEI) of 5, on a scale of 0-8. A 0 would be something like a lava flow on Hawaii that you could generally walk or run from, and 8 would be a supervolcanic eruption like Yellowstone (640,000 years ago and 2.1 million years ago) in the United States or Toba (74,000 years ago) in North Sumatra, Indonesia.
Based on a history of explosive activity at the volcano, the Indonesian authorities are maintaining the current hazard zone of up to 12km from the summit of Mount Agung.
It’s still considered more likely than not that it will erupt, but the question remains: when?
Peat means different things to different people. To many Irish people, it means fuel. To the Scottish, it adds a smoky flavour to their whisky. Indonesia’s peatlands, meanwhile, are widely known as the home of orangutans, the palm oil industry, and the persistent fires that cause the infamous Southeast Asian haze.
Indonesians, and other people with ties to these peatlands, have a range of perspectives on the value of peat – both commercial and otherwise.
Here we explore them through the eyes of four fictitious but representative characters.
Peatland is my land. As migrants from Java, my family now have our own house and our own crops. In some years there have been terrible fires, with smoke so thick we can’t even see the end of our street, and all of our food crops burn. But in other years, the rice and corn grow well, my family eat fish every day, my wife smiles, and our children grow tall.
In Java we had no land of our own, and I worked as a farm labourer. Here in Sumatra we have our own peatland. It is different from Javanese soil but we work hard to tend our crops, watering them in the dry season and protecting them from fire.
A big palm oil company has trained me and 50 other men from our village in firefighting. We have uniforms and water-holding backpacks, and I have learned about when the fire will come. They are helping us to protect our palms, and their own palms, of course. My palms are still young, but in a few years I will sell the palm oil fruit to the company, and then my boys can go to high school in town – as long as the palms don’t burn, God willing.
Floods are a harder problem. How can I protect my land? The government dug canals to drain the peatland before we came, but they are not big enough to hold all the water that comes from the heavens and the floods come more and more often.
The official in Jakarta
Peatland is our burden. Indonesia has fertile land, rich oceans… and then there are the peatlands. It is always either too wet to use, or so dry that it burns.
Other Southeast Asian governments want us to end the fires and haze single-handed, but Indonesia isn’t the only one to blame; peatland fires are a regional problem.
We are caught between domestic and international pressures. Develop our peatlands to lift our people out of poverty, or preserve them for orangutans and carbon storage. Of course, the Indonesian people are my priority.
When I studied agriculture at university in Brisbane in the 1990s, my classmates were a little fuzzy about where Indonesia is, let alone what happens here. Now, when our ministry visits Canberra, I feel sad to see “Palm Oil Free” displayed prominently on supermarket products. Westerners don’t understand that not all palm oil is grown on peatlands, that it is a healthy oil and a highly efficient crop perfectly suited to tropical conditions.
Our ministry is working hard to ensure that Indonesia develops our peatlands sustainably, restoring and rewetting degraded areas and working with the local people to find economic uses for wet peat. My son wants to follow in my footsteps and work on peatlands too, and has applied to study sustainable development at university in Singapore.
So while peatlands are currently a source of national embarrassment, many minds are focused on transforming them into the goose that lays the golden egg for Indonesia.
Peatland is good, profitable land. For too long we have considered it wasteland – too wet, too far away. But technology from peat-rich countries like Finland and Canada is helping us to use tropical peatlands for people.
My pulp and paper company has half of its plantations on peatlands, which produce more than a third of our pulpwood. My silviculture (forest management) team works closely with my environmental manager and PR team to ensure that our plantations are grown according to best practice, and that our shareholders and clients know it.
The community benefits in the regions around our plantations are easy to see. The village that my parents came from has electricity now, and big modern houses have replaced the old wooden ones. We have paved the road and our taxes support the government’s new health centre and primary school.
The Indonesian government doesn’t want any more fires, and neither do we – we don’t want our plantations to burn! But the new regulations that require rewetting the peat are a big challenge for us. What will grow in wet peatland?
I lie awake at night worrying about my company’s future. What species can we diversify into? Should we move away from pulp and into bioenergy? Are we putting enough money into R&D? Should I spend more on lobbying? My son is studying for an MBA in the United States, but will there still be a profitable business for him to join when he graduates?
The orangutan carer
We rescued Fi Fi from an area that used to be peatland forest but has been cleared for palm plantations. With no food and nowhere to make a nest, Fi Fi and her mother gradually got weaker and weaker, until workers at the plantation noticed and called us. The mother died before we could help her.
That was nine months ago, and I’ve been caring for Fi Fi around the clock since then in a babysitting team with my friend Nurmala. Fi Fi loves cuddles, milk and fruit, just like my children did at her age.
It is a good job, and we have a great team. Everyone is passionate about protecting the orangutans and the forest. We would like to be able to release Fi Fi once she has learned all her forest skills. Orangutans can look after themselves from about seven years old. But they need a lot of space.
Peatland fires, logging and oil palm planting destroy more forest every year, so places for Fi Fi to be released are hard to find. My brothers and sisters are all happy to stay living near our family home, and when I’m not here looking after Fi Fi, I always have my nieces and nephews on my knee.
I love to have them close, but when the dry season fires come and the haze is so thick I can’t even see my brother’s house across the street, I sometimes wish they had flown a bit further from the nest. Last year we were in and out of the health clinic for a month with my niece’s breathing problems.
I spend all my time caring for precious little ones – both human and orangutan – but the issues themselves are too big for me to fight.
People are central to the problem of tropical peatland fires. In their natural state, tropical peat swamp forests are too wet to burn. Drainage, installed by people for forestry, palm oil, roads, mining and other development, lowers the water table and dries out the peat. Many peat fires smoulder for months, from the start of dry season in July until the monsoon returns in November.
These fires have a wide range of negative effects: on local health, regional economies and the global carbon cycle. Indonesia’s president, Joko Widodo, has created a new Peatland Restoration Agency, and announced policies to restrict burning and draining of the peat beyond a maximum water table depth of 40cm below the surface. However, action is still disjointed and ministries are, at times, working at cross purposes.
The truth is that only when enough people value wet peatlands will the fires be prevented. Wet peatlands are great for orangutans and the global climate, but how about local smallholders, government officials and business investors? Saving peatlands will require creating value for these people too.
What crops can be profitably grown with a water table high enough to prevent burning? How can smallholders tap into a carbon trading market? Rather than cutting trees to send their children to school, can they earn more money by protecting the carbon stored in peat? Can villagers be empowered to make a better living from ecotourism than illegal logging?
Humans are integral to Indonesia’s tropical peatlands. And they must be at the centre of the solutions too. Otherwise the fires will keep burning – and none of the four people whose stories we’ve heard want that.