Western Ghats: geography, biodiversity and why they matter

Geography: a 1,600 km wall along the coast

The Western Ghats, also known as the Sahyadri, run roughly parallel to India's western coast for about 1,600 km, from the Gujarat-Maharashtra border region in the north to Kanyakumari at the southern tip of the peninsula. They form the steep, faulted western edge of the Deccan Plateau, separating it from the narrow coastal plain along the Arabian Sea.

The range passes through six states: Gujarat, Maharashtra, Goa, Karnataka, Kerala and Tamil Nadu. Anamudi in Kerala is its highest peak. Published figures for the range's total area vary between about 140,000 and 160,000 sq km, because different sources draw the boundary of the range differently.

A biodiversity hotspot

The Western Ghats are one of the world's eight hottest hotspots of biological diversity, a title earned by the sheer number of species that live here and nowhere else. The western slopes carry tropical evergreen and semi-evergreen rainforest, the eastern slopes carry deciduous forest, and the high altitudes hold a distinctive mosaic of shola forest patches set in rolling montane grassland.

Endemic animals include the Nilgiri tahr of the high grasslands and the lion-tailed macaque of the rainforest fragments, both endangered, and the range is one of the world's most important tiger strongholds. One educational summary counts 325 globally threatened species in the region. In 2012 UNESCO inscribed 39 properties in the range — national parks, wildlife sanctuaries and reserve forests — as a World Heritage Site.

Rivers and the monsoon

The Ghats shape India's rainfall. They intercept the moisture-laden southwest monsoon winds from the Arabian Sea, forcing the air to rise, cool and drop heavy rain on the western slopes, while the Deccan Plateau behind them lies in a rain shadow. That single wall of hills is a major reason the west coast is wet and the interior plateau is dry.

The range is also a watershed. The Godavari, Krishna and Kaveri rise here and flow east to the Bay of Bengal, watering much of peninsular India, while shorter, faster rivers such as the Periyar, Bharathappuzha and Sharavathi flow west to the Arabian Sea and suit hydroelectric power. Protected areas include the Nilgiri Biosphere Reserve and Silent Valley National Park, within a network of two biosphere reserves and 13 national parks.

Why the Ghats are under pressure

The same forests that hold so many unique species are being lost to plantation conversion, quarrying, roads and unplanned construction on fragile slopes. Replacing natural forest with single-species plantations of acacia, rubber or eucalyptus can look like forest cover in statistics while supporting only a fraction of the original wildlife.

Conservation therefore focuses on keeping the natural mosaic intact: protecting the shola-grassland highlands that the Nilgiri tahr depends on, linking fragmented rainforest for the lion-tailed macaque, and keeping the river catchments forested so that the water supply of peninsular India is not damaged at its source.

Editorial disclosure

This article was researched and published with AI assistance. No human prepublication review is claimed. Report factual errors through our contact page.