Derived from the Malay words "orang" and "hutan" (meaning "person" and "forest", respectively), the solitary and introspective orangutan, or "person of the forest", shares about 97% of its DNA with humans and plays a crucial role in forest health and viability within its island ecosystem.

Orangutans are one of the five great apes, along with gorillas, chimpanzees, bonobos and humans. Other than humans, orangutans are the only great ape naturally found in Asia. Their range once extended throughout most of southern Asia, and their fossil remains have been found as far north as southern China.

Orangutans are now restricted to isolated populations in northern Sumatra and Borneo (within the countries of Indonesia and Malaysia) and prefer rainforest within the lowland river valleys and floodplains of their respective islands. All three species of orangutan, the Bornean, Sumatran and Tapanuli, are considered critically endangered.

 

Orangutan population sizes have been drastically declining over the last 40 years. The primary threats to orangutans include habitat loss and fragmentation, fires, illegal hunting and trafficking, and gaps in information on distribution and numbers. 

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Sumatran

Orangutans Are A
Semi-Solitary Species

Unlike the other great apes, orangutans are semi-solitary.  While they will interact with other orangutans (barring a few exceptions), they largely do not live together.  The main exception is the mother/infant relationship.  Infant orangutans will stay with their mother for 6-10 years.  Additionally, females will associate with other females and adolescents that are not their own.  
 

Flanged males however, are primarily solitary, except for breeding.  Male orangutans will use their long call to signify their territory to other males. The vocalization wards off encroaching males and communicates to eligible females. 

 

Orangutans will gather or travel together when fruit resources are abundant.

Wild juvi 2 - Mike Crowther, Indianapoli

Orangutans Are Arboreal

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Orangutans are arboreal, meaning they live predominantly in the canopy of the rainforest. Having an arm span that is 1.5 times their height,  orangutans are able to climb through the treetops and travel from tree-to-tree with relative ease.  Their feet also act as a second pair of hands, allowing them to adeptly grip the branches as they forage for food. 

 

Orangutans utilize the treetops for food, traveling and nesting.  They build large nests up in the trees using branches and leaves, which help create mattresses, pillows and blankets.  Some wild orangutan communities will even use plants that repel insects.  Orangutans either make or re-use an old nest every night, but it is uncommon for them to share a nest with another orangutan.

While rare, they do go to the ground for traveling longer distances and collecting food or water.

Why Should We Care? 

Orangutans play a vital role in their environment, acting as forest "horticulturists" and dispersing important seeds as they eat and travel.  

 

Additionally, orangutans have an incredibly slow reproductive rate, with females producing their first offspring at around 15 years of age. Offspring are dependent on mom for the first 7-8 years, learning critical skills for survival in the rainforest. This means that one female will only have about 2-3 offspring in her lifetime

With increasing anthropogenic pressure, coupled with the slow reproductive rate, all three orangutan species have been pushed toward extinction at an increasing rate.  

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