Despite their apparent remoteness and inaccessibility, the Himalayas have not been spared human-induced biodiversity loss. People have lived in the mountains of the Himalayas for thousands of years. In recent decades, greater access to the global market has increased the demand for natural resources in the area encouraged both immigration from outside (such as Arunachal Pradesh) and movement within the region (such as in Nepal). As a result, populations are growing in the most productive ecosystems, which are also some of the richest in biodiversity.
Today, remaining habitat in the Himalaya is patchy. The steadily increasing population in the hotspot has led to extensive clearing of forests and grasslands for cultivation, and widespread logging. Both legal and illegal logging often occurs on extremely steep slopes, resulting in severe erosion. Although cultivation has a general upper limit of about 2,100 meters on slopes exposed to monsoons, people farm crops such as barley, potato and buckwheat at high elevations in the inner valleys and transmontane regions, and in some areas, such as Jumla, Kashmir, Lahoul, and Ladakh, there are major agriculturally based population centers well above this elevation. The land is also often cleared in the summer months for livestock; the use of fire to clear land poses an additional threat to forest land, as fires sometimes spread out of control. The conversion of forests and grasslands for agriculture and settlements has led to large-scale deforestation and habitat fragmentation in Nepal, and in the Indian States of Sikkim, Darjeeling, and Assam.
Large areas of remaining habitat in the hotspot are highly degraded. Overgrazing by domestic livestock, including cattle and domesticated yak, is widespread in the lowlands and alpine ecosystems. The flora of fragile alpine meadows has been overexploited for traditional medicine (because medicinal plant collectors invariably uproot the entire plant, regrowth is retarded). Fuelwood collection and non-timber forest product extraction, both for domestic consumption and export, has inflicted severe damage to some forest ecosystems. Unplanned and poorly managed tourism has led to environmental deterioration. Political unrest, often in the form of insurgencies, also threatens the integrity of some protected areas.
In addition to habitat loss and degradation – which has led to perhaps no more than 25 percent of the original vegetation in this hotspot still intact – poaching is a serious problem in the Himalayan Mountains, with tigers and rhinoceros hunted for their body parts for traditional Chinese medicine, while snow leopards (Uncia uncia, EN) and red pandas (Ailurus fulgens, EN) are sought for their beautiful pelts.
Other threats to biodiversity and forest integrity include mining, the construction of roads and large dams, and pollution due to the use of agrochemicals.