An exclusively marine mammal, the only species in the family Dugongidae, up to 5.8 m long, with no fins or hindlimbs, forelimbs resembling paddles, a notched tail, and a moderately cleft upper lip. It feeds mainly on sea-grass, hence its common name ‘sea cow’, and migrates within a range depending on the availability of sea-grass. Dugongs occur in coastal waters from the Red Sea to Taiwan and northern Australia.