Return to the Wild - Evolving perspectives on Canadian wildlife
The orca's range surrounds Canada in all its three oceans.

Did you know?

The orca is the second most widely distributed mammal in the world — the first being humans.

Scientific name: Orcinus orca
Average weight: 6,500 kg (male)
4,500 kg (female)
Average height: up to 1.8 m (male)
less than 1 m (female)
Average length: up to 9 m (male)
up to 7.7 m (female)
Average lifespan: 30 years – can live over 50 years (male)
50 years – can live over 80 years (female)
Several orcas swim along Canada's West Coast.

About

Biology

Also called the killer whale because of its predatory nature, it is the largest of the dolphin family and is easy to identify due to its characteristic black and white skin pattern.

A tall dorsal fin sits in the middle of its long, rounded body, and on the male this usually sticks straight up, while on the female it is often smaller and curved. Each orca has a grey area called a “saddle patch” behind this dorsal fin. At the front end of the animal, the mouth is slightly v-shaped with teeth measuring up to five centimetres in length.

Throughout the lifetime of the animal, it often accumulates natural scars and scientists use these to identify the different orcas in the many studies on the large mammal.

Habitat and behaviour

Depth is not much of an issue as the orca lives in both coastal and offshore waters that range from freezing to tropical temperatures. There are several varieties of orcas: resident orcas which form extremely stable pods in separate northern and southern communities, feeding mainly on fish; transient orcas which form smaller groups that travel constantly, preferring a diet of mammals; and offshore orcas which are the least well-known group because they are rarely seen. Of the latter, only 250 have been catalogued so far.

Similar to other tooth whales (one of two types of whale, the other being baleen), the orca uses sound to pinpoint prey, a technique called echolocation. Although it has good vision, dark or murky water makes it difficult for any species to see. The orca compensates by emitting a series of clicking sounds that bounce off fish and other objects. Using this natural sonar, the mammal paints itself a picture of the surroundings, which it uses to hunt and navigate. The orca will also call out to other orcas within its family group, or pod; each pod has its own dialect, distinct from all others.

Pods can include anywhere from 5 to 50 of these highly social animals. Led by females, there are very tight bonds within the pods — especially between the mother and her son or sons.

Range

The orca surrounds Canada in all of its three oceans. While it has been spotted in Hudson Bay and the Gulf of St. Lawrence, it is uncommon in the Atlantic and Arctic oceans. You are most likely to see a Canadian killer whale off the southern coast of British Columbia. As well, it is found worldwide, even as far away as the Antarctic region.