Orca

Also known as the killer whale, the orca (Orcinus orca) is the largest member of the dolphin family, and one of the most distinctive of all cetaceans. The killer whale’s strikingly marked black and white body is unmistakable, being black on the upperparts, sometimes with a light grey ‘saddle patch’ behind the dorsal fin, and white on the underparts, lower jaw and undersides of the tail. White lobes extend up the sides of the body behind the dorsal fin, and there is a white, oval patch behind each eye. In newborn killer whales, the white areas of the body have an orange hue. Both the male and female killer whale have a broad, rounded head and snout, an enlarged forehead, large, paddle-shaped pectoral fins and a large dorsal fin. However, males grow larger than females, and on reaching maturity become stockier and develop disproportionately larger fins, with adult males easily recognised by the tall, erect dorsal fin, which is the largest of any cetacean, growing to an impressive 1.8 metres in height. The female killer whale, in contrast, has a more backward-curving dorsal fin, which grows to just 70 to 90 centimetres in height. The shape of an orca’s dorsal fin and saddle patch are unique to each individual. Found throughout all of the world's oceans, the killer whale is thought to be the most widespread mammal after humans. The killer whale commonly hunts marine mammals and it is the world's largest predator of warm-blooded animals.