The largest delphinid of its family, it reaches up to 10 meters in length. The particularly high dorsal fin, especially in the male, and the black and white colour pattern makes this species easy to identify. It has a white abdomen from the hemi-mandibles to the urogenital cleft, having two white patches above and directly behind each eye. The rest of the body is black, with a grey saddle-like region behind the dorsal fin. Very robust in appearance, it has a hierarchal social structure. Orcas have a cosmopolitan distribution, preferring coastal waters. Their diet is very diverse, from other marine mammals (ex.: harbour porpoises and seals) to fish, cephalopods and occasionally turtles and sea birds. There are records of occurrence of this cetacean all over the Portuguese coast, normally associated with the migratory route of Bluefin tuna (Thunnus thynnus), one of their favourite preys.