Despite its name, the killer whale, also known as an orca, is a member of the oceanic dolphin family. Ranging from 6 to 8 metres (20 to 26 ft) in length and weighing over 6 tonnes (945 stone), the killer whale is the largest species of dolphin. They are easy to identify due to their distinctive black and white colouring.

Killer whales are carnivores and hunt small sharks, seals, sea lions, dolphins, whales, penguins, seagulls, squid, octopuses, stingrays, crabs and sea turtles. Its size and strength make it one of the fastest marine mammals, with a top speed of over 56 km/h (30 knots).

The killer whale's dorsal can extend up to six feet above its body and is often be seen gliding through the surface of the water. This causes some people to mistake killer whales for sharks.

Female killer whales, known as cows, are generally smaller than the males (bulls), ranging from 5 to 7 m (16 to 23 ft) in length and weighing about 3 to 4 t (472 to 629 stone). The cows are often tamed and trained to do tricks for audiences in marine shows. They have even starred in movies, such as 'Free Willy' (1993). Regardless of their tame nature, killer whales are naturally wild and have been known to harm or kill their attendants on rare occasions.

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