human impactsExtremely high population pressure in both countries of this hotspot has seriously stressed the region's biodiversity. There are more than one billion people in India and almost 20 million in Sri Lanka. Nearly 50 million people occur in the hotspot overall, at a density of 260 people/km² (one of the highest in hotspots). It is likely that no more than about 25 percent of the extent of original native vegetation remains in relatively pristine condition today.The forests of the Western Ghats have been selectively logged and highly fragmented throughout their entire range. Forests have been converted to agricultural land for monoculture plantations of tea, coffee, rubber, oil palm, teak, eucalyptus, and wattle, and are also cleared for building reservoirs, roads, and railways. Encroachment into protected areas further reduces the extent of forests. Grazing by cattle and goats within and near protected areas causes severe erosion on previously forested slopes. Much of the remaining forest cover consists of timber plantations or disturbed secondary growth. Today, approximately 20 percent of the original forest cover remains in more or less pristine state, with forest blocks larger than 200 km² found in the Agasthyamala Hills, Cardamom Hills, Silent Valley-New Amarambalam Forests, and southern parts of the South Kannada District in Karnataka State. Remaining forest patches are subject to intense hunting pressure and the extraction of fuelwood and non-timber forest products. Uncontrolled tourism and forest fires are additional concerns.The growth of populations around protected areas and other forests has led to increasing human-wildlife conflict. Raiding elephants cause crop loss, and leopards kill livestock. Compensation for farmers is generally inadequate, and wild animals are often killed or injured in an attempt to reduce further damage.In Sri Lanka, two-thirds of the people live in the wet zone, which harbors greater endemism than the comparatively less populated and more extensive dry zone. Most of the island’s rainforests were cleared originally for the cultivation of cinchona (a medicinal drug containing quinine and related compounds) and coffee, which gave way later to tea and rubber. The remaining forests cover only 4.6 percent of the wet zone. This remaining forest comprises some 140 fragments; the three largest are Peak Wilderness (250 km²), the Knuckles Hills (175 km²), and the Sinharaja World Heritage Site (90 km²), but the majority of these fragments are less than 10 km² in extent.One of the most prevalent threats to the remaining forests is encroachment into protected areas. Small-scale tea planters and farmers are increasingly utilizing protected forests, and cardamom cultivators in the Knuckles Range and Peak Wilderness areas clear the forest understory and extract firewood. In general, poaching and the extraction of forest products (timber, firewood, medicinal plants) are a problem in almost all forest reserves, and contribute to habitat fragmentation and significant edge effects. Also, the unrestricted use of agrochemicals by farmers and planters in these areas poses a serious threat to ecosystem services and groups such as amphibians. Finally, invasive species pose a growing threat, especially to aquatic habitats.
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© Patricio Robles Gil/Sierra Madre
The Western Ghats and Sri Lanka Hotspot harbors important populations of the endangered Asian elephant (Elephas maximus, VU).
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