According to National Geographic, the entire Tapanuli orangutan species are in danger of extinction due to the construction of a hydroelectric dam in the middle of its remaining habitat in Sumatra's Batang Toru Forest. The Bornean orangutans Pongo pygmaeus , found on the island of Borneo, are listed as critically endangered, despite having the largest population remaining out of all the species of orangutans. Bornean orangutans are divided into three subspecies: northwest Bornean, northeast Bornean, and central Bornean.
The northwest Bornean orangutans are the most threatened subspecies, with a population of approximately 1, individuals. Its habitat has been drastically affected by logging and hunting, and its population is fragmented and small.
The northeast Bornean orangutans are the smallest in size, with a population of about 16, individuals. The central Bornean orangutans have the largest population, with about 35, individuals. The Sumatran orangutan's Pongo abelii range extended from the entire island of Sumatra to Java. They are restricted to the north of Sumatra, with a majority living in the provinces of North Sumatra and Aceh. This orangutan species is broken up into nine separate populations, of which seven are viable in the long term.
Each of these populations has about or more individuals. The Tapanuli orangutan Pongo tapanuliensis was most recently discovered as a distinct species in They are the most endangered of the great apes, having a population of less than in the wild. The Batang Toru Ecosystem has over , acres of land, with about square miles of it dedicated as an orangutan habitat.
Orangutans' range once encompassed a large portion of Asia, but their populations have drastically declined due to deforestation and other threats. The remaining individuals are only found in the islands of Borneo and Sumatra.
The name 'orangutan' originates from two different Malay and Indonesian words: 'orang' human and 'hutan' forest. Orangutan thus means 'human of the forest'. The orangutan shares no less than 97 percent of its DNA with humans. They therefore share many physical similarities with humans.
Orangutans live exclusively in Sumatra and Borneo in Southeast Asia, and it is the only great ape found outside of Africa. Until recently, we have known of only two different orangutan species. One in Sumatra Pongo abelii and one in Borneo Pongo pygmaeus. However, the Tapanuli orangutan Pongo tapanuliensis , a third orangutan species, was discovered in Sumatra in According to IUCN, all three species are critically endangered.
The Bornean orangutan species, Pongo pygmaeus, is further divided into three subspecies: P. The remaining wild populations of orangutans live in the rainforest, usually in low-lying peat forests and other fertile rainforests in Borneo and Sumatra. They primarily live above the ground and in the forest canopy, and they are the largest arboreal mammals.
The largest remaining species of orangutans is the Bornean species Pongo pygmaeus. However, recent estimates reveal that only between 50, and , orangutans live in the wild in Borneo today. Even more critical is the pressure on the orangutans in Sumatra, where populations of less than 14, Pongo abelii and Pongo tapanuliensis orangutans also face the overwhelming risk of extinction. Orang-utans usually give birth to a single young, or occasionally twins.
Orang-utans stay with their mothers for the first years of their life. An infant rides on its mother's body and sleeps in her nest until it is able to survive on its own. The long time taken to reach sexual maturity, the long interbirth periods, and the fact that orang-utans normally give birth to just a single young mean that orang-utans have an extremely low reproductive rate.
This makes orang-utan populations highly vulnerable to excessive mortality, and means that populations take a long time to recover from population declines. The rest comprises young leaves and shoots, insects, soil, tree bark, woody lianas, and occasionally eggs and small vertebrates. They obtain water not only from fruit, but also from tree holes.
Three species There are three species of orang-utan - the Bornean, Sumatran and Tapanuli - which differ a little in appearance and behavior. The Bornean and Sumatran species have shaggy reddish fur, Sumatran orangutans have longer facial hair.
Sumatran orang-utans are also reported to have closer social bonds than their Bornean cousins. The Sumatran orang-utan is almost exclusively arboreal. Females virtually never travel on the ground and adult males do so only rarely. This is in contrast to Bornean orang-utans, especially adult males, which more often descend to the ground. A third species of orangutan was announced in November, With no more than individuals in existence, the Tapanuli orangutan is the most endangered of all great apes.
This new third species lives in North Sumatra, but is genetically and behaviorally distinct from the two other species. An international team of scientists described the new species in Current Biology. The Tapanuli orangutan Pongo tapanuliensis is distinguished from other orangutan populations based on morphological and genomic evidence.
The new species is endemic to square miles of upland forest in the Batang Toru Ecosystem of Sumatra and is believed to have been isolated from other orangutan populations for 10,, years. Flanged male Bornean orangutan Pongo pygmaeus. Tree emerging from tropical rainforest. Key facts. Did you know? Meaning of name Orang-utan means 'man of the forest' in Malay language. Species news. But today Asia's great ape is confined to just two islands, Borneo and Sumatra. As the orang-utan's range has decreased so have its numbers.
A century ago, there were probably , orang-utans - around four times as many as there are today. Their dense forest home makes it difficult to determine population sizes, but the Bornean orang-utan is estimated to number around , individuals, while there are under 14, Sumatran orang-utans. The Sumatran orang-utan is now restricted to the north of Sumatra.
It depends on high-quality primary forests, and is less able to tolerate habitat disturbance than Bornean orang-utans.
The population is currently fragmented into 13 populations in 21 forest blocks. Only 6 of these populations boast more than animals and are therefore regarded as viable in the long term, but even these groups are under threat due to ongoing habitat loss. The Bornean orang-utan was once distributed throughout large areas of Kalimantan Indonesia and Sarawak and Sabah Malaysia on the island of Borneo.
Most Bornean orang-utans are now found in Kalimantan, especially along the east coast. The majority of wild populations are located outside of protected areas, in forests that are exploited for timber production or are in the process of being converted to agriculture.
Three subspecies live in different parts of the island: Northwest Bornean orang-utan is the most threatened subspecies with over 3, remaining. Northeast Bornean orang-utans are the smallest in size. Around 16, live in Sabah and parts of eastern Kalimantan. Central Bornean orang-utans are the most common subspecies with around 35, surviving.
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