Sumatran Orangutan

Sumatran Orangutan

Sumatran orang-utan

Kingdom
Phylum
Subphylum
Class
Order
Suborder
Infraorder
Family
Genus
SPECIES
Pongo abelii
Population size
7,300
Life Span
35-50 years
Top speed
6
4
km/hmph
km/h mph 
Weight
45-90
99-198
kglbs
kg lbs 
Height
90-140
35.4-55.1
cminch
cm inch 
Length
1.3-1.8
4.3-5.9
mft
m ft 

The Sumatran orangutan (Pongo abelii) is one of the three species of orangutans. Critically Endangered, and found only in the north of the Indonesian island of Sumatra, it is rarer than the Bornean orangutan but more common than the recently identified Tapanuli orangutan, also found in Sumatra. Its common name is based on two separate local words, "orang " ("people" or "person") and "hutan " ("forest"), derived from Malay, and translates as 'person of the forest'.

Di

Diurnal

Fr

Frugivore

He

Herbivore

In

Insectivores

Fo

Folivore

Li

Lignivore

Ar

Arboreal

Zo

Zoochory

Is

Island endemic

No

Nomadic

Sc

Scansorial

Te

Terrestrial

Te

Territorial

Vi

Viviparous

Br

Browsing

Po

Polygynandry

So

Solitary

No

Not a migrant

S

starts with

Appearance

Compared to the Bornean species, Sumatran orangutans are thinner and have longer faces; their hair is longer with a paler red color. Males develop throat pouches and fleshy pads on their cheeks but these are narrower and less pronounced than those of male Bornean orangutans.

Video

Distribution

Geography

Continents
Subcontinents
Countries
Regions
Biogeographical realms

Sumatran orangutans occur on Sumatra, in Indonesia, and are restricted to just the northern tip of the island. They live in primary lowland tropical forests, including mangrove, riparian forests, and swamp forests.

Sumatran Orangutan habitat map

Climate zones

Sumatran Orangutan habitat map
Sumatran Orangutan
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Habits and Lifestyle

Sumatran orangutans lead very solitary lives, during the day moving slowly in search of food through the trees. Up to 60% of an orangutan’s time is spent foraging and eating, and, although they can occupy large home ranges, half a mile a day is the most they usually travel. At night, they build a nest for sleeping up high in the canopy out of folded branches. They are not very territorial, sharing their home ranges with others, sometimes feeding alongside other orangutans around especially abundant fruit trees. Males will stake their claim to their territory by emitting long calls, deep calls from their throat poach which echo through the forest to attract females and also to warn off potential rivals.

Seasonal behavior

Diet and Nutrition

Sumatran orangutans are primarily frugivores, favoring fruits consisting of a large seed and surrounded by a fleshy substance, such as durians, lychees, jackfruit, breadfruit, and fig fruits. Insects are also a huge part of the orangutan's diet; the most consumed types are ants. Their main diet can be broken up into five categories: fruits, insects, leaf material, bark, and other miscellaneous food items.

Mating Habits

MATING BEHAVIOR
REPRODUCTION SEASON
December-May
PREGNANCY DURATION
9 months
BABY CARRYING
1 infant
INDEPENDENT AGE
8-9 years
FEMALE NAME
female
MALE NAME
male
BABY NAME
infant

These animals are polygynandrous; this means that two or more males mate with two or more female orangutans. Most mating occurs during rainy seasons, the heaviest fruiting months (December to May). After a gestation of about 9 months, the female builds a new nest high in a tree, where her single infant is born. The young clings to its mother for safety and remains at her side during the first few years. Infants may be weaned by the age of three, but they will stay with their mother until at least the age of 8 or 9 years while being taught special skills for forest survival. Sumatran orangutans are slower breeders than other primates, with females bearing a maximum of three babies during their lifetime. Females become reproductively mature by the age of 12 years and males at an average of 19 years old.

Population

Population threats

The primary threat to Sumatran orangutans is the loss of habitat. These animals have a unique vulnerability to exploitation due to their extremely long inter-birth period, usually, eight years, which makes them the world’s slowest-breeding primates. Recent political instability in the area of their habitat has led to increased illegal logging in areas that are protected, and increased capture of infants to be sold for the illegal pet trade.

Population number

According to the IUCN Red List, the total Sumatran orangutan population is around 7,300 individuals. In addition, a population that is being established in Jambi and Riau Provinces in the Bukit Tigapuluh National Park, numbers around 70 animals and is reproducing. Overall, Sumatran orangutans’ numbers are decreasing today and they are classified as critically endangered (CR) on the list of threatened species.

Ecological niche

Sumatran orangutans have a big role in the Sumatran lowland rainforests and are therefore considered a keystone species. Orangutans are important for dispersing seeds, being consumers of a wide variety of fruit, and they also help to maintain the diversity of woody plants of the rainforest. In addition, they prune and assist in regenerating plant growth, as they choose to eat only green leaves and stalks.

Fun Facts for Kids

  • These orangutans are highly intelligent animals and some populations on Sumatra have learned how to use tools, and they pass on their knowledge through generations. They use sticks to probe in termite mounds for termites and to extract the seeds of the large Neesia fruit, avoiding its stinging hairs.
  • Orangutans are known to watch villagers cross the local waterways in boats and then unfasten a boat themselves and ride across the river.
  • Orangutans are the slowest breeders of all land mammals, reproducing every 7 or 8 years only.
  • Orangutans have 32 teeth, the same as humans.
  • Mosquitoes are pests for orangutans as they are for humans, and orangutans use branches to swish them away.
  • When the sun is hot or it rains, an orangutan may hold a leafy branch over its head to avoid the heat or the rain.
  • Baby orangutans cry when hungry, whimper when hurt, and will smile at their mothers.
  • Orangutans may get the water from natural bowls created in the trees they lived around. They may even drink water from the hair on their arms when rainfall is heavy.

Coloring Pages

References

1. Sumatran Orangutan Wikipedia article - https://en.wikipedia.org/wiki/Sumatran_orangutan
2. Sumatran Orangutan on The IUCN Red List site - http://www.iucnredlist.org/details/39780/0

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