Orcinus orca
Killer Whale
A student web page designed by Elizabeth Mary

Family Delphinidae Order Cetacea Suborder Odontoceti

The Killer Whale, largest member of the dolphin family, exists in more parts of the world than probably any other cetacean. Killer Whales live both in the open ocean and close to shore and are more common in the colder, more productive waters than in the Tropics.

Killer whales are black or deep brown in colour, with striking white patches above the eye, and from the lower jaw down to the belly. They are also marked with a fainter grayish-white saddle patch just under and behind the dorsal fin. Mature males typically reach lengths of up to 9.8 m (up to 32 ft) whereas mature females reach lengths of up to 8.5 m (up to 28 ft). All killer whales have a prominent triangular dorsal fin in the middle of the back that can grow as tall as 1.8 m (5.9 ft) in the adult male. The flippers of both sexes are large and oval, unlike those of any other toothed whale.

Killer whales may travel alone or live in groups of 2 to more than 50 animals. They feed on fish, squid, marine birds, seals, and even other cetaceans. They generally cooperate during hunting, especially when feeding on large, warm-blooded animals such as penguins, seals, and porpoises. Killer whales have even been known to prey on blue whales, the largest species on earth. In most areas, killer whales have specialized feeding habits. In the Pacific Northwest regions, resident populations feed mainly on salmon and other near-shore fishes, while transient populations feed primarily on harbour seals and porpoises. In several places in the southern hemisphere, killer whales actually beach themselves as they rush ashore to take seals or sea lions. To return to the water they twist their bodies back and forth to return to the water.

To gather information about their surroundings, killer whales use echolocation; that is they send out high-frequency clicks that bounce off prey and other objects and interpret the returning echoes. Killer whales communicate by means of rapid-fire click trains that sound like rasps and screams. However, when they are on the prowl for marine mammals, which have acute underwater hearing, they can be silent for hours at a time.

Killer whale groups or pods seem to be remarkably stable as males and females usually stay in their natal pods, or groups, for life. However, researchers believe that mating does not occur between members of the same pod as often as it does between members of different pods, to keep inbreeding to a minimum. The female gives birth to a single calf 16 or 17 months after copulation. The calf is then nursed by the mother for 14 to 18 months.

Killer Whales are an important subject of mythology for many people, especially the Native Americans of the Pacific Northwest. These whales have not been hunted extensively by humans. However, in the Pacific Northwest and Icelandic waters they have been hunted occasionally by shore whaling operations, and captured for aquarium show animals.

Links: check out these links for more on killer whales!

OceanLink's acoustic page - hear Killer Whale sounds!

Vancouver Aquarium's Conservation in Action - Killer Whales

National Geographic's Killer Whale site

British Columbia's Wild Killer Whale adoption program 

Whales on the net - Discovering whales

 to Marine Biodiversity index