The mammal species within Rila National Park and its surroundings are 62 and include taxa of high conservation value, such as brown bear, gray wolf, wildcat, least weasel, European pine marten, marbled polecat, wild boar, red deer, roe deer, chamois, European ground squirrel, as well as the glacial relict European snow vole. The bird species are 156; of the 120 are nesting within Rila National Park. These include three relicts — boreal owl, Eurasian pygmy owl and Eurasian three-toed woodpecker, and species that require special conservation measures like short-toed snake eagle, golden eagle, peregrine falcon, black stork, Eurasian woodcock, western capercaillie, hazel grouse, rock partridge, grey-headed woodpecker, black woodpecker, white-throated dipper, wallcreeper and Alpine chough among others. There are 18 reptile, 10 amphibian and 12 fish species. The invertebrate fauna discovered so far includes 4186 species and is expected to rise to over 7000; of them 34 are endemic to Rila, 123 — to Bulgaria and another 123 — to the Balkans.