There are numerous threats to the viability of the remaining wild orangutan population in Indonesia and Malaysia. Estimates of the numbers left in the wild vary from 16,000 to 65,000 with around 5,000 disappearing every year.
The most important risk factor for orangutans is the loss of habitat and the fragmentation of orangutan forests. Orangutans originally roamed from India to South China to the islands of Sumatra and Borneo. In 2001, some fossil orangutan teeth were found on the island of Flores further to the East in the Indonesian archipelago, extending the living range than first thought. Now only a few places with wild orangutans remain and these are found only on the islands of Sumatra and Borneo.
Indonesia's human population has increased from around 10 million at the beginning of the 20th century to over 200 million people. During this same period, the orangutan population has dwindled by more than 90%. Both people and orangutans like the same alluvial river habitat. These areas provide rich land for fruit tree cultivation and forest. However the forest can be easily logged due to its proximity to the river and so the best orangutan-forests disappear first. In a human versus orangutan conflict, the orangutan is rarely the winner.
Suitable orangutan habitat in Indonesia and Malaysia has declined by more than 80% in the last 20 years. A deadly combination of logging (legal and illegal) and expansion of the oil palm industry is largely responsible.
A 2007 report, "The Last Stand of the Orangutan: State of Emergency" from the United Nations Environment Programme (UNEP), estimated that illegal logging accounts for more than 70% of the timber harvested in Indonesia and that it is occurring in 37 of the country's 41 national parks. The industry is driven by excess saw mill capacity and better returns for timber producers than utilising legally harvested timber.
In addition to the direct loss of habitat, there are flow-on effects from the opening up of the forest and introduction of network roads:
- The creation of "forest islands", areas of land too small to support an orangutan population results in animals caught on these islands starving to death or turning to desperate food seeking measures.
- The vulnerability of these areas to forest fires increases. The large quantities of dead wood littering the once forest floor provide the perfect combustion material for Kalimantan's famous uncontrollable infernos.
- Microclimate changes impact fruiting in the forests. When local conditions deteriorate, orangutans are forced to move to new areas of forest which quite often have fewer fruit trees. In times of drought orangutans will head to the rivers. It is under these conditions that human attitudes towards orangutans turn from tolerance to regarding them as pests. Orangutans are killed as they raid people's orchards in an attempt to find food.
This was evident during the terrible drought and fires of 1997 and 1998. During this time literally thousands of orangutans perished either from starvation, fires or at the hands of people whose gardens they entered.
Cleared land is often destined for planting of oil palm which is the world's most productive oil seed. While not native to the region, Malaysia and Indonesia have become the world's largest producers of plam oil with plantations in Indonesia estimated to cover over 5 million ha in 2005. The increase in demand for the product is being driven by not only the food and cosmetic industry but more recently its usage as a biofuel.
The combined effect of logging and oil palm expansion resulted in Indonesia having the world's highest deforestation rate in 2006 according to the UNEP report. It concluded that up to 98% of the orangutan habitat in Borneo and Sumatra may be destroyed by 2022 without urgent action.
Another threat to the survival of the wild orangutans is disease. North of the Mahakam river in East Kalimantan, for instance, Hepatitis B has been found in a wild orangutan population. It may very well be that diseases like this have lead to the extinction of orangutans over large areas of South East Asia.
Wild orangutan numbers are also affected by the illegal pet trade - particularly the socially inclined baby. For every baby that makes it to the backstreet markets of Bangkok or Taiwan another two have perished. And to "harvest" the babies a further five mothers have been killed.
Easier access and encroachment of people into the orangutan forests also leads to increased hunting of orangutans for meat, babies, skulls or, more recently for orangutan penises.
Each of these factors, when considered on their own, would be sufficient to impact on the survival of a wild animal species. However, for orangutans, the situation is further complicated by their comparatively slow reproduction and maturity rate.
A female orangutan will not reach sexual maturity until she is about fourteen to sixteen years of age and will only bear offspring once every eight to ten years. Males reach their full sexual maturity at nineteen or twenty years of age. Reproduction is also effected by the abundance of food. When food supplies dwindle so too does the orangutan's reproduction rate. As a result their numbers decline possibly becoming too low for the orangutans to survive in the long term.
The survival of the orangutan in the wild is becoming more precarious with every passing year - with extinction in the wild likely to be 2010 for Sumatran Orangutans and 2015 for Bornean Orangutans. The fight to save of orangutans is most commonly depicted using the appealing images of orangutan orphans - each of one of whom has lost a mother and possibly been a witness to her death. These images, while important in their ability to attract people to join the fight to save the orangutan, do not portray the full horror of this unfolding tragedy. The following images depict other aspects of the impact of humans on the orangutan.
Source: Orangutans.com.au