Golden spirit: Survival of the shy primate is closely tied to the health of Western Ghats

As dawn arrives in the Western Ghats, the hushed night is broken with a piercing hoot: high-pitched yet fitting with the natural rhythm of the landscape. It is the call of the Nilgiri langur, a black-bodied primate with a golden mane and amber eyes, perched high across the branches. Its slender tail, often longer than its body, helps it balance as it leaps across the canopy.

As the name suggests, the langur— a term used for the subset of Old World monkeys endemic to the Indian subcontinent—is found mostly in the Nilgiri hills, along with the Silent Valley, Wayanad, Periyar and Agasthyamalai ranges of Kerala and the Mudumalai, Kalakkad-Mundanthurai and Mukurthi National Parks of Tamil Nadu. A fairly shy primate, it prefers to occupy remote habitats with few humans nearby. Scientists encounter most Nilgiri langurs at higher elevations. Its preferred habitat includes evergreen and semi-evergreen forests, as well as shola-grassland mosaics at higher altitudes of 300-2,000 metres.

Also known as hooded leaf monkey, the arboreal primate lives in small troops led by a dominant male and a few females with their young. Its diet consists mainly of tender leaves, shoots, flowers and fruits. Like other leaf-eating monkeys, it has a multi-chambered stomach that helps digest cellulose-rich food efficiently. By dispersing seeds and pruning vegetation, Nilgiri langurs help maintain forest health and regeneration.

For tribal communities of the Western Ghats, the Nilgiri langur is more than a forest dweller. Tribal groups like the Kattunaikkan, Kurumba and Mudugar communities of Kerala and the Muthuvan community that lives on the Tamil Nadu-Kerala border, consider it a forest spirit and a symbol of vigilance and harmony with nature. Its loud, echoing calls are seen as omens of rain or warnings of danger. Elders in Attappady still listen for the change in pitch that signals a leopard has entered the valley. Some Irula storytellers speak of a black-faced guardian of fig and jackfruit groves which must never be disturbed.

Tribal healers in parts of Idukki, Palakkad and Wayanad speak of old recipes where langur fat is mixed with herbs to heal wounds and increase strength. This may be a reason why the langur’s populations dipped long even before habitat loss became a major threat. Though such practices have diminished, poaching persists sporadically in remote areas. Conservation officers have recorded stories of hunters in the 1960s-70s who would hunt for troops in winter, when they believed the fat was strongest.

While there is no precise recent census, estimates suggest a total population of around 20,000 Nilgiri langurs across southern India. Kerala is believed to host the largest share, with roughly 3,000 individuals. Tamil Nadu’s Nilgiri forest division recorded 535 individuals in 57 Nilgiri langur troops in 2018, spread across six forest ranges. Smaller populations survive in Karnataka’s Brahmagiri and Pushpagiri ranges. This fragmented distribution, however, leaves many of the troops isolated and vulnerable.

The Nilgiri langur is classified as Vulnerable on the International Union for Conservation of Nature (IUCN) Red List. Conservation efforts include its listing under Schedule I of the Wild Life (Protection) Act, 1972, which prohibits hunting, trading and killing with harshest penalties for violations, and Appendix II of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora). Despite this, deforestation, expanding plantations and unregulated tourism continue to threaten the langur populations. Conversion of native forests into tea, coffee and eucalyptus plantations has broken up their habitat.

Today, conservationists see the Nilgiri langur as a flagship species for the protection of the southern Western Ghats. Its survival is closely tied to the health of montane forests that regulate rainfall, feed rivers like the Periyar and Bharathapuzha, and sustain millions of people. Protecting the langur means preserving this ecological network.

Both Kerala and Tamil Nadu have begun integrating Nilgiri Langur conservation into larger forest restoration projects. In Silent Valley, Wayanad and Kalakkad-Mundanthurai, forest departments regularly map canopy corridors to help troops move between fragmented patches. Kerala’s forest department has included the langur in biodiversity monitoring programmes, while Tamil Nadu is conducting population studies in Nilgiri and Anamalai divisions. Efforts are also underway to involve local communities, reviving traditional respect for the species and reducing human interference.

This article was originally published as part of the December 16-31, 2025 print edition of Down To Earth