Informasi mengenai orangutan diperoleh dari situs web Orangutan Foundation International dengan izin.

Fakta Singkat!

· Kelas: Mamalia

· Bangsa  : Primata

· Induk Suku:  Hominoidea

· Suku: Pongidae

· Marga: Pongo

· Jenis: abelii (Orangutan Sumatra) dan pygmaeus (Orangutan Kalimantan/Borneo)

· Panjang: jantan – sekitar 101 cm dari ujung kepala sampai panggul; betina – sekitar 76 cm

· Berat: jantan – 50-130 kg; betina – 30-50 kg

· Rentang hidup: 60 tahun atau lebih

· Masa kehamilan: sekitar 8,5 bulan

· Jumlah bayi yang dilahirkan: biasanya 1, sangat jarang 2 (dalam penangkaran)

· Berat badan saat dilahirkan: 1,5 – 2 kg

· Jarak kelahiran: 8-9 tahun (di hutan)

· Usia dewasa: jantan – sekitar 15 tahun; betina – 12 tahun (dalam penangkaran)

· Status konservasi:  Pongo pygmaeus (Orangutan Kalimantan/Borneo) – endangered; Pongo abelii (Orangutan Sumatra) – critically endangered

Fakta Menarik!
· Dalam bahasa Indonesia, “orang” berarti orang/manusia dan utan berasal dari kata hutan. Oleh karena itu, orangutan berarti “orang dari hutan.”

· Rentangan kedua lengan orangutan lebih panjang dari badan mereka – lebih dari 2 meter jika diukur dari ujung jari ke ujung jari – dan digunakan untuk “mencengkram”. Di atas tanah, mereka berjalan dengan kaki dan tangannya, yaitu dengan menggunakan telapak atau kepalan tangan.

· Ketika orangutan jantan berusia 15 tahun, mereka akan memiliki bantalan pipi, yang terlihat menarik bagi orangutan betina.

· Ketika orangutan jantan berkelahi, mereka saling menyerang satu sama lain dan mematahkan ranting. Jika itu tidak menakutkan lawan, mereka akan saling bergulat dan menggigit.

· Untuk beberapa tahun pertama sejak dilahirkan, orangutan muda berpegang erat pada tubuh induknya yang berkeliling hutan mencari buah-buahan. Selanjutnya, mereka akan mengikuti induknya berpindah dari pohon ke pohon.

· Seperti halnya manusia, orangutan memiliki ibu jari yang ‘opposable’. Begitu pula dengan ibu jari kakinya.

· Orangutan memiliki kekuatan yang luar biasa. Hal tersebut memungkinkan mereka untuk berayun dari satu dahan ke dahan lain, dan bergantung jungkir balik dari dahan ke dahan dalam waktu yang lama untuk memperoleh buah-buahan dan memakan daun-daun muda.

Kiri: Distribusi peta orangutan di dunia

Species Information- extracted from the Orangutan Foundation UK website with permission

About a million years ago, orangutans lived throughout much of Asia, from Java in the south, right up into Laos and southern China. Today they are found only on the islands of Borneo and Sumatra.

Asia's only great ape, the orangutan has recently been re-classified as belonging to two distinct species, reflecting their geographical distribution: Pongo pygmaeus (on Borneo) and Pongo abelii (on Sumatra).

 

Orangutan Distribuition Map

The two species show slightly different physical characteristics. Sumatran orangutans have a narrower face and longer beard than the Bornean species. Bornean orangutans are slightly darker in colour and the males have wider cheek pads than their Sumatran relatives. Behavioural differences have also been observed between the two species; Sumatran orangutans are more frugivorous (fruit-eating) and there is evidence of tool use than in Bornean orangutans.

Under the IUCN (International Union for Conservation of Nature) Red List, the Sumatran orangutan is classified as critically endangered and the Bornean as endangered.

Bornean Male Orangutan

Sumatran Male Orangutan

Diet

Primarily frugivorous, orangutans have an important role as seed dispersers. They selectively choose ripe fruit whose seeds are adapted to withstand passage through the orangutans' gut. Once excreted, the seeds find themselves in their own little compost pile, which helps them to become established.

Over 400 food types have been documented as part of the orangutans' diet, and although it consists mainly of fruit, in times of scarcity orangutans will shift their eating habits to lower quality food, such as bark, leaves & termites, rather than travel to a different area. As well as acting as seed dispersers, orangutans help to open up the forest canopy. This allows light to reach the forest floor, which once again helps the forest regenerate.

Behavior

Orangutans are wholly dependent on trees for their existence. They are perfectly adapted to life in the forest - they sleep in nests, feed predominantly on fruit and travel with ease through the forest canopy, rarely descending to the forest floor.

Orangutans are almost unique amongst the primate species. All other apes and monkeys are social and gregarious, whilst the orangutan is semi solitary, the largest group being a mother and two offspring. Females are less solitary and may spend up to 25% of their time with other orangutans. In contrast, male orangutans will spend less than 9% of their time in association with other orangutans. Sumatran orangutans are more social and this social behaviour usually coincides with the simultaneous fruiting of the fig tree, which doesn't occur in Borneo .

Courtship lasts between 3-10 days and it is the female who, not wanting to share her food source, initiates the final separation. The male has no role in the raising of his offspring. It is thought that this solitary lifestyle evolved due to erratic fruiting, leading to competition for food. With a predominately frugivorous diet, containing relatively few calories for such a large body size, the orangutan needs to forage for 60% of the day, with the other 40% spent sleeping and resting.

Orangutans are the slowest breeding of all primates and, at almost eight years, have the longest inter-birth interval of any land-based mammal. The female orangutan reaches puberty at ten years and will normally have her first infant between the age of 12 and 15. Offspring are dependent on their mothers for at least five years and with a life expectancy of 45 years plus, females will normally have no more than three offspring. With these factors combined, the orangutan population, especially small fragmented populations, are at considerable risk. They don't have the capacity to recover from disasters that may strike a population. A slight rise in the adult female mortality rate by just 1-2% can drive a local population to extinction.

A larger map of the distribution of orangutans can be found here