Killer whale

The orca, or killer whale, is the largest member of the dolphin? family (order Cetacea, subfamily Delphinidae) and a versatile predator.

Orcinus orca

Public domain picture from U.S. National Oceanic and Atmospheric Administration [full size image 1118KB]

It is also called the great killer whale or grampus.

The adult male is especially distinctive with black skin, a white chest and sides, paddle-shaped flippers, a heavy and stocky body, a rounded head and a bright white patch above and behind the eye, and a large (1.8m) dorsal fin. The female and juvenile are less distinctive and can be confused with various dolphin? and porpoise? species. The orca can grow to a length of up to 9m and weigh 4-5,000 kg in the male and 7m 2.5-3,000 kg in the female.

Most live in the polar regions but they are found in all seas including the Mediterranean and Arabian Sea. At sea they are usually seen in pods of 5-25 whales, although groups of up to 150 have been seen together.

The Orca's diet depends entirely on availability (although pods can specialize and thus ignore potential prey) but includes twenty species of cetaceans, five species of pinniped? (seals), thirty species of fish, seven species of bird and two species of squid?, in addition to a variety of other sea creatures, occasionally including larger whales such as fin whales, minke whales or gray whales. It is from their attacks on other whales they gained their name. It is believed they require around 60kg of food daily.

Man is their only predator.