Killer whale | |
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Transient killer whales near Unimak Island, eastern Aleutian Islands, Alaska | |
Size compared to an average human | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Synapsida |
Class: | Mammalia |
Order: | Artiodactyla |
Infraorder: | Cetacea |
Family: | Delphinidae |
Genus: |
Orcinus Fitzinger, 1860 |
Species: | O. orca |
Binomial name | |
Orcinus orca (Linnaeus, 1758) |
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Orcinus orca range (in blue) | |
Synonyms | |
Orca gladiator |
Orca gladiator
The killer whale or orca (Orcinus orca) is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. Killer whales have a diverse diet, although individual populations often specialize in particular types of prey. Some feed exclusively on fish, while others hunt marine mammals such as seals and dolphins. They have been known to attack baleen whale calves, and even adult whales. Killer whales are apex predators, as there is no animal that preys on them. Killer whales are considered a cosmopolitan species, and can be found in each of the world's oceans in a variety of marine environments, from Arctic and Antarctic regions to tropical seas.
Killer whales are highly social; some populations are composed of matrilineal family groups (pods) which are the most stable of any animal species. Their sophisticated hunting techniques and vocal behaviours, which are often specific to a particular group and passed across generations, have been described as manifestations of animal culture.
The IUCN (International Union for the Conservation of Nature) currently assesses the orca's conservation status as data deficient because of the likelihood that two or more killer whale types are separate species. Some local populations are considered threatened or endangered due to prey depletion, habitat loss, pollution (by PCBs), capture for marine mammal parks, and conflicts with human fisheries. In late 2005, the Southern Resident Killer Whales, the population that inhabits British Columbia and Washington state waters, were placed on the U.S. Endangered Species list.