Introduction

Nilgiri langur is an endemic primate of the Western Ghats of South India. It is a leaf-eating Old World monkey known for its glossy dark body and brownish to golden-brown head. Its scientific name is Semnopithecus johnii. It is one of the important mammalian species associated with the evergreen and shola forests of the Western Ghats.

Distribution and habitat

The Nilgiri langur is found only in the Western Ghats, mainly across Kerala, Tamil Nadu, and Karnataka. It inhabits evergreen forests, moist deciduous forests, montane shola forests, and high-elevation forest patches. Animal Diversity Web notes that it occurs roughly between 300 and 2,500 metres, and is often associated with shola-grassland landscapes in the higher Western Ghats.

Important protected areas associated with its distribution include:

• Silent Valley National Park
• Mukurthi National Park
• Mudumalai landscape
• Bandipur region
• Periyar landscape
• Eravikulam and other Western Ghats forest tracts

Physical features

Nilgiri langur is a distinctive arboreal monkey.

Its main identifying features are:

• glossy black or dark brown body
• brownish, golden-brown, or chestnut-colored head and neck region
• long tail
• slender body adapted for movement in trees

It differs from the lion-tailed macaque in both body form and tail structure. Unlike the lion-tailed macaque, it does not have a silver mane or lion-like tufted tail.

Behaviour and food habits

Nilgiri langur is mainly arboreal and diurnal. It lives in social groups and spends most of its time in the forest canopy. Animal Diversity Web describes it as using the middle or lower canopy for resting and movement.

Its diet is mainly herbivorous and consists largely of:

• leaves
• shoots
• fruits
• flowers
• seeds in some cases

Because of its feeding behavior, it plays an ecological role in forest regeneration and plant community dynamics.

Conservation status and threats

Nilgiri langur is currently listed as Vulnerable on the IUCN Red List. Its population is threatened mainly by habitat fragmentation, forest degradation, and human pressure in the Western Ghats landscape. Reports and species notes also mention hunting pressure in some areas.

The main threats include:

• habitat loss
• fragmentation of forest patches
• decline in canopy connectivity
• local hunting pressure
• disturbance from roads and settlements

Importance

Nilgiri langur is important because it is an endemic primate of the Western Ghats, and therefore a significant indicator of the health of South Indian forest ecosystems. Its conservation is closely linked with the protection of evergreen and montane forests of the Nilgiri and adjacent hill systems. It is also one of the notable flagship mammals of the Nilgiri Biosphere Reserve and Western Ghats conservation landscape.

Key points to remember

• Scientific name: Semnopithecus johnii
• Endemic to the Western Ghats
• Found in Kerala, Tamil Nadu, and Karnataka
• Arboreal and diurnal primate
• Mainly leaf-eating
• IUCN status: Vulnerable
• Threatened by habitat fragmentation and hunting pressure

Conclusion

Nilgiri langur is a vulnerable, endemic primate of the Western Ghats and one of the characteristic mammals of South Indian forest ecosystems. It should be remembered as a canopy-dwelling langur of evergreen and shola forests, important for both biodiversity conservation and the ecological identity of the Nilgiri–Western Ghats landscape.