The orca is the largest member of the dolphin family.
Also called the killer whale, the orca belongs to Delphinidae, the oceanic dolphin family. Adult males can reach about 9.8 metres and weigh several tonnes, while females are generally smaller. Its tall dorsal fin, black-and-white pattern, and robust body make it distinctive.
Orcas live in every ocean, from polar waters to tropical seas. Different populations often specialize in different prey, including fish, rays, seals, dolphins, and whales. Their hunting techniques and vocal traditions can vary between groups, and these learned behaviors are passed through generations.
The name “killer whale” reflects old observations of orcas hunting other whales; it does not mean they are whales in the taxonomic sense. Biologically, they are toothed cetaceans and the largest dolphins. They live in stable social groups known as pods, although pod structure differs among populations.