The International Union for the Conservation of Nature (IUCN)'s has placed the hoolock gibbbon on its Red List establishing the species as a major critically endangered species in Bangladesh.
Globally, the primate species has an endangered status.

A male hoolock gibbon deftly clambers to the most extreme branches of a tree in Lawachhara National Park in March 2017
Syed Zakir Hossain/Dhaka TribuneAccording to Prof Monirul H Khan, from Jahangirnagar University’s Zoology Department, there are about 200 members of the Western hoolock gibbon (hoolock hoolock) living in the north-east region of Bangladesh, particularly in greater Sylhet and Chittagong regions.

Globally, hoolock gibbons are considered to be merely endangered, whereas in Bangladesh they are critically endangered
Syed Zakir Hossain/Dhaka TribuneHoolock gibbons are arboreal primates, which mean they spend their entire lives on trees. They seldom come down to the ground, with the lowest average height a hoolock gibbon comes down to during its lifetime is 15 feet.
A hoolock’s size ranges from 60-90cm and weighs between 6-9kg. Their diet consists of different types of fruits, leaves and insects.

Hoolock gibbons are the second largest among the gibbons
Syed Zakir Hossain/Dhaka TribuneThe life expectancy of a hoolock is about 25 years.
The male of the species have black fur with white brows whereas the female have a grey-brown fur. The species are also found in the seven sister states of North-east India.

The Bangla name for Hoolocks is Ulluk
Syed Zakir Hossain/Dhaka TribuneThe number of hoolocks is declining mostly due to deforestation. As their natural habitat shrinks with each passing day, their numbers fall, threatening the primate species with extinction.