Hoolock Gibbon

Recently, a stranded family of Hoolock gibbons was successfully rescued in the Lower Dibang Valley district of Arunachal Pradesh by forest and wildlife officials, highlighting ongoing conservation efforts for India’s only ape species.

About Hoolock Gibbon

Hoolock gibbons belong to the family of gibbons, which are the smallest and fastest of all apes.
They inhabit tropical and subtropical forests of Southeast Asia.
The hoolock gibbon is one of the 20 gibbon species found globally and holds special significance as the only ape species found in India.

Distribution of Hoolock Gibbon

• The species is distributed across India, Myanmar, Bangladesh, and southern China.

• In India, hoolock gibbons are found south of the Brahmaputra River in the states of:

  • Assam

  • Meghalaya

  • Arunachal Pradesh

  • Nagaland

  • Manipur

  • Mizoram

  • Tripura

• Hollongapar Gibbon Sanctuary (Assam) has the largest population of hoolock gibbons in the country.

Species Classification

• Western Hoolock Gibbon (Hoolock hoolock) – Found across most of Northeast India

• Eastern Hoolock Gibbon (Hoolock leuconedys) – Restricted to eastern Arunachal Pradesh

Key Characteristics

• Diurnal and arboreal, spending most of their life in trees

• Move primarily by brachiation using their long arms

• Monogamous, forming lifelong pair bonds

• Live in small family groups

• Communicate through loud vocalisations

• Average lifespan: around 25 years

Conservation Status

IUCN Red List

• Eastern Hoolock Gibbon: Vulnerable

• Western Hoolock Gibbon: Endangered

Legal Protection in India

• Both species are listed under Schedule I of the Wildlife (Protection) Act, 1972, providing the highest level of legal protection.

Threats (Value Addition)

• Habitat loss and fragmentation due to deforestation and infrastructure projects

• Forest fires and agricultural expansion

• Low reproductive rate due to monogamous behaviour and small family size