It is endemic to the Philippines, where it occurs in primary, mature secondary and disturbed forests on 11 islands: Luzon and Marinduque (race hydrocorax), Samar, Leyte, Bohol, Panaon, Biliran, Calicoan and Buad (race semigaleatus), Dinagat, Siargao, Mindanao (plus Balut, Bucas and Talicud) and Basilan (race mindanensis). It is still common locally, notably in the Sierra Madre of Luzon, but continues to suffer from substantial hunting pressure and widespread loss of habitat. They are one of the largest birds in a tropical lowland forest (Clarido,2017)