Uganda's Bwindi Impenetrable National Park and Mgahinga Gorilla National Park protect some of the most biologically diverse tropical forests in East Africa. Both parks conserve rare and dwindling Afromontane and Afro-alpine. Mgahinga represents the Ugandan share of the Virungas Volcanoes range and is contiguous with the Virungas National Park in the Republic of Congo and Parc National des Volcans in Rwanda. Up to fifty mountain gorillas use Mgahinga for part of the year. It is also home to numerous other rare mammals and eleven regionally endemic bird species. Bwindi is particularly rich in biodiversity. It contains at least 120 species of mammals, including ten primates and half the world's population of 600 mountain gorillas. Bwindi also holds forests that are rich in tree, butterfly, vertebrate, invertebrate, reptile, amphibian, and bird species. The two parks serve as important water catchments and sources of forest products for local communities.