The Sinharaja Forest Reserve is a hilly virgin rainforest. It is a treasure trove of endemic species, including trees, insects, amphibians, reptiles, birds and mammals. Because of the dense vegetation, wildlife is not easily seen here. The commonest larger mammal is the endemic Purple-faced Langur. An interesting phenomenon is that birds tend to move in mixed feeding flocks, invariably led by the fearless Greater Racket-tailed Drongo and the noisy Orange-billed Babbler. Of Sri Lanka\'s 26 endemic birds, the 20 rainforest species all occur here, including the elusive Red-faced Malkoha, Green-billed Coucal and Sri Lanka Blue Magpie.