earth from spaceConservation of endangered species is a complex and complicated process that encompasses many forms and ideas. While the focus on the rescue and rehabilitation of individual animals, or the halting of poaching and the illegal pet trade is imperative if orangutans and other species are to survive, at its heart, conservation involves the protection of ecosystems, and the vast areas of land In which animals live and which humans depend on.


The entire planet is a vast network of ecosystems and ecosystem services that control and stabilize everything on our planet. The functions of intact ecosystems are so intricate and varied it is impossible to name all of them, but ecosystems are responsible for the purity of the air we breathe, for the distribution and quality of the water we drink, for generating oxygen, stabilizing our climate, decomposing and detoxifying detritus, creating soils and recycling nutrients essential to agriculture (Sekercioglu, 2010).


There are few ecosystems more important than forests. Orangutans are the largest arboreal animal in the world, and the only great ape found in Asia. As large primates who feed chiefly on fruit and are found only in the lowland tropical rainforests of Borneo and Sumatra, their future survival relies on the future of Asia’s tropical rainforests. Although studies indicate orangutans can survive in degraded and disturbed tropical rainforest (Ancrenaz et al, 2007), they simply cannot survive in any other type of ecosystem.


rainforestinthenightBut the future of the forest is not just important for the future of orangutans. Humans rely on them as well. Forests are often referred to as the lungs of the earth, on account of the role they play in regulating the world’s atmosphere. Through a process known as photosynthesis, forests, more specifically the plants that cover their trees, absorb atmospheric carbon dioxide and covert it in to organic compounds, including oxygen (Sekercioglu, 2010).  Oxygen, which comprises 20% of the air we breathe, allows the atmosphere to essentially ‘clean’ itself through the oxidation of compounds such as carbon monoxide (Sodhi et al, 2007). These cycles are so intricately linked that any changes in one component can have a drastic effect on another (Sekercioglu, 2010). Studies have shown that forests play an important role in the regulation of the world’s climate, with tropical rainforests, like those in which orangutans live, acting as heat and humidity pumps, transferring heat from the tropics to more temperate zones, and releasing water vapor that comes back as rain (Sodhi et al, 2007), and there are fears that if the integrity of these forests is not maintained, these systems could be compromised and lead to warmer and more extreme weather conditions in future.


rainForests are also vital for the role they play in the provisioning and regulation of water resources. During downpours, the vegetation layers of forests act as a block, intercepting rain drops that would ordinarily fall directly to the ground. By intercepting rainfall and decreasing the speed in which they fall and hit the ground, forests reduce the risk of flooding, something extremely important in tropical climates prone to downpours that can deposit large amounts of rainfall in short spaces of time (Bradshaw et al, 2007). Forest ecosystems alone regulate a third of the planet’s watersheds, on which nearly five billion people depend (Millennium Ecosystem Assessment, 2005), and, despite covering just 6% of the world’s surface, tropical rainforests receive nearly half of the worlds rainfall (Myers, 1997). In south east Asia, an intact old growth tropical forest is likely to intercept at least 35% of all rainfall, while a palm oil plantation is likely to intercept just 12% (Ba, 1977), and extensive flooding in Kalimantan over the last few years has been attributed to the conversion of primary rainforest to palm oil plantations (Jakarta Post, 2008). It has been estimated that a 10% decrease in forest cover in developing countries would lead to a flood frequency increase of between 4% and 28% (Bradshaw et al, 2007), while studies have shown that the impact of the 2004 tsunami, which ravaged areas of Indonesia, Thailand and Sri Lanka, would have been reduced if the hardest hit areas had not been stripped of their mangrove forests, which act as buffers against floods and rising water levels (Dahdouh-guebas et al, 2005). The latter is a particularly important function. The 230,000 hectare Tripa peat swamps in northern Sumatra are an essential freshwater reservoir for local people, but also saved countless lives during the tsunami, by acting as a buffer to rising tides. Studies have also shown that these forests, which harbor a large population of Sumatran orangutans, protect communities from flooding, as the peat swamps control and regulate the flow of rain and river water to the coast (Ruysschaert, 2009).


soilMaintaining the integrity of the forest ecosystem is also important for the role it plays in maintaining the quality and conservation of soil, and preventing soil erosion. Soil is ‘one of the most critical but also most underappreciated and abused elements of natural capital, one that can take a few years to lose and millennia to replace’ (Sekercioglu, 2010), and soil provides six major functions; moderating the hydrologic cycle, providing physical support to plants, retention and delivery of nutrients to plants, disposal of wastes and dead organic matter, renewal of soil fertility and regulation of major element cycles (Daily et al, 1997). Due to soil’s enormous water retention capacity, most of the rain that falls every year throughout the world is absorbed and gradually released to feed plants, underground aquifers and rivers. However, intensive cultivation, usually after deforestation, can reduce this capacity, leading to floods, erosion, pollution and further loss of organic matter (Pimentel et al, 1995), and it is estimated that, today, 11 million km2 of land is affected by high rates of soil erosion (Milennium Ecosystem Assessment, 2005), with 75 billion tons of soil being eroded from terrestrial ecosystems every year (Pimental & Kounang, 1998).


Although erosion is a natural process that releases nutrients and makes them available to plants, the loss of forest or vegetation cover exposes soils and increases the impact of rain, wind and other elements, causing run offs, often in to water reservoirs, and landslides. Studies in East Kalimantan have shown that, in logged forests, trails become rivers of mud just a few minutes after rainfall, that rivers draining logging areas soon become highly polluted (Chin, 1987), and that the steep slopes and hilly topography of this province make soil erosion likely whenever the forest cover is broken (Stadtmueller, 1990). Field studies in 1986 in the province also show that converting rainforest in to rice fields, and failing to put soil conservation initiatives in to practice, saw large rates of soil erosion and loss of soil fertility (Secrett, 1986), something still seen today, where, in the tropics, farming can result in the loss of half the soil nutrients in less than a decade (Bolin and Cook, 1983). Soil erosion is both devastating for the global economy, with the direct costs of erosion totaling around $250 billion per year (Pimental et al, 1995), and for local people and wildlife. In Tanjung Puting National Park in central Kalimantan, a 400,000 hectare expanse of forest with a large orangutan population, mining activities and illegal logging have caused increased erosion and run off in to the Seknoyer river, which has turned the naturally clear black water in to a muddy brown, decreasing visibility, which is the likely cause of an increase in crocodile attacks on humans, and causing concern for local people, who rely on the river and its fish for survival (Mongabay, 2006).


swamp_canalsThe draining of peat swamps, for agriculture and timber extraction, has also become one of the biggest threats to forest ecosystems in Indonesia. Peat swamps are forests with waterlogged soils that prevent dead leaves and wood from fully decomposing, which, over time, creates a thick layer of acidic peat. South East Asian countries have over 20 million hectares of peat swamp forests (World Rainforest Movement, 2002), and in Indonesia, the two national parks with the highest densities of wild orangutans, Sebangau and Tanjung Puting, are predominantly peat swamp forests. Peat swamps are like sponges, and absorb large amounts of rain and river water during the wet season, controlling floods and run off, and releasing it slowly during the dry season. Despite the forests invaluable ecological functions, Indonesia has seen large conversion of peat swamps for agriculture, and it is predicted that a further 3 million hectares of peat swamps will be converted for palm oil plantations by 2020 (Hooijer et al, 2010). This conversion, which involves draining the peat and drying it out, reduces the forests ecological functions, and makes it susceptible to fire. Fire does not normally spread in the moist, closed canopy environment of undisturbed peat swamp forests (Harrison et al, 2009), but dry peat smolders for long periods and burns down to the water table, and peat swamp forest trees, which are not naturally adapted to fire, have a high post-fire tree mortality (Harrison et al, 2009).


The protection of forest ecosystems in Indonesia and Malaysia is important for the future of both orangutans and people, from both an ecological and economic point of view, but protecting ecosystems does just not just mean protecting the trees and large mammals that inhabit them, it means protecting the millions of species that work together, in intricate, tightly woven cycles. It has been said that when humans alter ecosystems, it is often the large mammals that are the first to disappear. This can have a devastating effect on the forest ecosystem and particular species, particularly those species of fruit that rely on digestion and dispersal by large mammals, and studies have shown that the loss of large carnivores can see a surge in the number of herbivores, which then deplete plant species, in turn causing a decline in the density and diversity of other species (Ripple & Bescheta, 2006), while the loss of large herbivores can cause the opposite effect, a large increase in the number of plants, and a corresponding increase in the number of small herbivores, like rodents, and their predators, such as snakes (McCauley et al, 2006). But while orangutans and other charismatic large mammals in the forests of south east Asia, the leopards, tigers, elephants and rhino’s, play an important part in the forest ecosystem, the part is no more important than the millions of species of birds, reptiles, insects, plants, fungi and others that work together to provide the services we and the world depend on for our survival.


Albert Einstein once reportedly said “if the bee disappears from the face of the earth, man would have no more than four years to live. No more bees, no more pollination……no more man”. Whether or not he actually said this, and whether or not that timeframe is technically accurate or not, it nevertheless stresses the importance of the smaller, less charismatic species, and the invaluable role they play in the wider ecosystem  To protect orangutans, and ourselves, we must protect all of them.






Ancrenaz, M., Dabek, L. & O'Neil, S. (2007). The Costs of Exclusion: Recognizing a Role for Local Communities in Biodiversity Conservation. PLoS Biol 5(11)


Ba L.K. (1977). Bio-economics of trees in native Malayan forest. Department of Botany, University of Malaya.


Bolin, B. & Cook, R. B. (1983). The major biogeochemical cycles and their interactions. John Wiley & Sons, UK


Bradshaw C.J.A., Sodhi, N.S., Peh, K.S.H. & Brook, B.W. (2007). Global evidence that deforestation amplifies flood risk and severity in the developing world. Global Change Biology, Vol 13, 11, pp. 2379-2395


Chin, S.C. (1987). Deforestation and environmental degradation in Sarawak. Wallaceana


Dahdough-Guebas, F., Jayatissa, L.P., Di Nitto, D., Bosire, J.O., Lo Seen, D. & Koedam, N. (2005). How effective were mangroves as a defense against the recent tsunami? Current Biology, Vol 15, 12, pp. 443-447


Daily, G.C. (1997). Nature’s Services: societal dependence on natural ecosystems. Island Press


Harrison, M.E., Page, S.E. & Limin, S.H. (2009). The global impact of Indonesian forest fires. Biologist, Vol 56, 3, pp. 156-163


Hooijer, A., Page, S., Canadell, J.G., Silvius, M., Kwadijk, J., Wosten, H. & Jauhiainen, J. (2010) . Current and future CO2 emissions from drained peatlands in Southeast Asia. Biogeosciences, 7, pp. 1505-1514


McCauley, D.J., Keesing, F., Young, T.P., Allan, B.F. & Pringle, R.M. (2006). Indirect effects of large harbivores on snakes in an African savanna. Ecology, 87 (10), pp. 2657-63


Millennium Ecosystem Assessment (2005). Ecosystems and human well being; synthesis. Island Press


Mongabay (2006). Saving orangutans in Borneo.


Myers, N. (1997). The world’s forests and their ecosystem services. Natures Services.


Pimental D. & Kounang N. (1998). Ecology of soil erosion in ecosystems. Ecosystems, 1. pp. 416-426


Pimental, D., Harvey, C., Resosudarmo, P., Sinclair, K., Kurz, D., McNair, M., Crist, S., Shpritz, L., Fitton, L., Saffouri, R. & Blair, R. (1995). Environmental and economic costs of soil erosion and conservation benefits. Science, Vol 267, No. 5201, pp. 1117-1123


Ripple, W.J & Beschta, R.L. (2006). Linking a cougar decline, trophic cascade and catastrophic regime shift in Zion national park. Biological Conservation, Vol 133, pp. 397-408


Ruysschaert D., Singleton, I. & Sudarman, S. (2009). Inappropriate land use in the coastal Tripa peat swamps on the west coast of Aceh. PanEco Foundation.


Secrett C. (1986). The environmental impact of transmigration. The Ecologist.


Sekercioglu C.H. (2010). Ecosystem functions and services. In Sodhi, N.S. & Ehrlich, P.R.,editors,  Conservation biology for all. Oxford University Press, UK


Sodhi N.S., Brook, B.W. & Bradshaw, C.J.A. (2007). Tropical conservation biology. Wiley-Blackwell, Boston, USA


Stadtmueller, T. (1990). Soil erosion in east Kalimantan. Indonesian-German Forestry Project


World Rainforest Movement (2002). The environmental impacts of draining peat swamps. World Rainforest Movement.