• Body has a distinctive pattern with black on the back, white on the belly, white-grey "saddlepatch" behind the dorsal fin and white "eyepatch" located just behind the eye.

• Dorsal fin is short and curved in juvenile and female whales, whereas mature males will have a tall dorsal fin up to 1.8 metres in height.

• Tail flukes are black on top and white underneath.

• Group size ranges from 1-10 (Bigg's/transients) to 5-30 (residents) to 30-80 (offshores).

• Groups may be spread out across a body of water. In large aggregations, killer whales often surface in groups or in unison.

• Aerial behaviours common (e.g. breaching, spyhopping, tail-lobbing, pectoral fin slapping).

• Killer whales are widely distributed throughout the coast and can be found in inshore and offshore waters year-round.

• Three distinct ecotypes can be found in British Columbia: Resident, Bigg's (transient) and offshore killer whales.

1) Resident killer whales:

Resident killer whales range from SE Alaska down to the coast of Oregon, although in recent years some of the pods have been seen as far south as California in the winter months. Resident killer whales are salmon specialists, and Chinook salmon makes up the majority of their diet, year-round. These whales rely on echolocation to find their prey.

Resident killer whales live in a complex matriarchal society, in which sons and daughters with their mother throughout their lives, even after they have offspring of their own. These bonds remain strong between siblings even after the mother has died. In the resident assemblage, these family units are known as MATRILINES. A pod is a larger unit that is made up of one or more matrilines that travel together and may be related. A clan is a group of pods that share similar calls or dialects, indicating that they share a common ancestry and a more closely related to each other than to whales in other clans.

Resident killer whales are split into two populations, known as “Southern” and “Northern” residents. In over 30 years of research, members of the two communities have not been found in the same area at the same time.

The southern resident community consists of one clan (J clan) and 3 pods (J, K and L pods) and number only 75 animals. They are most commonly seen in the waters around Victoria and the San Juan Islands in the summer, although they may range north to Desolation Sound and as far south as California in the winter months. Southern resident killer whales are critically endangered, due to their small population size, reliance on endangered or threatened salmon runs for prey, high toxin loads and sensitivity to boat disturbance.

The northern resident community consists of 3 clans (A, G and R) and numerous pods within each clan. It numbers approximately 300 animals. Northern residents are most commonly seen in the waters around the northern end of Vancouver Island, and in sheltered inlets along B.C.’s Central and North Coasts. They also range northward into Southeast Alaska in the winter months. Northern resident killer whales are also threatened by the same factors as southern residents.

2) Bigg’s (transient) killer whales

Bigg’s killer whales were formerly known as ‘transients’.  In 2012, a push was made to rename this type of killer whale in memory of Dr. Michael Bigg.  Bigg’s killer whales range all along the west coast of North America, from California to Alaska. They are mammal-eaters, specializing on smaller marine mammals such as seals, sea lions, porpoises, dolphins, and occasional calves or juveniles of larger species such as grey whales and humpback whales. In fact, the term “killer whale” is derived from this type of killer whale, which is the only species of whale that kills other whales.

Bigg’s killer whale societies are based on a matriline structure, similar to resident killer whales, but offspring may disperse from their mothers once they reach maturity, especially females once they’ve had calves of their own.

For Bigg’s, traveling in smaller groups is important to be able to efficiently hunt and catch their prey. Unlike fish, marine mammals can hear very well underwater, so Bigg’s killer whales vocalize and echolocate very rarely while searching for their prey. Instead, they follow the coastline, checking each cove for unsuspecting prey and use passive listening to locate seals and small cetaceans. Bigg’s typically vocalize either during or directly following a kill.

3) Offshore killer whales

Very little is known about offshore killer whales because they tend to spend most of their time offshore along the continental shelf. Some groups have been sighted in inshore waters and even deep into coastal inlets. Offshore killer whales are typically encountered in groups of 30 – 70 whales or more. Little is known about their social structure.

It is thought that these killer whales eat large ocean fish such as sharks and halibut. Compared to transient and resident killer whales, offshore killer whales have a large proportion of nicks and scarring, possibly from catching sharks. The few offshore killer whales that have stranded had teeth that were significantly worn down, which would also occur from consuming sharks which have very tough skin.

Offshore killer whales are acoustically distinct from resident and transient killer whales, but little is known about how they use their calls and how this differs from resident and Bigg’s killer whale behaviour.

For more information about killer whales in B.C., please visit Ocean Wise’s Wild Killer Whale Adoption Program.