Habitat alteration and natural habitat causes the destruction of breeding grounds, shelter, and sources of food. Destruction of natural habitat is the primary threat to biodiversity. Natural habitats, which protect natural flora and fauna are being converted to human settlements, harbors, dams, reservoirs, crop-lands, grazing grounds, and mining sites. Deforestation deprives animal life of shelter and food. This decreases the population of many species. Migratory animals are also affected by deforestation because of the disturbance in their routes.