Coastal Resource Information System

Killer Whale

Killer whales are common in the study area year-round. Three races are known. The first race is comprised of a minimum of 310 "resident" animals. The second race is comprised of a minimum of 200 "transient" animals, and the third is comprised of a minimum of 200 "offshore" animals. Most sightings near the coastline are of "transient" animals. The resident population is increasing in numbers, but little is known about the status of the other two races. "Resident" animals occur sporadically throughout the study area, but are typically seen near the central part of the study area. At that time, they can be observed from nearshore areas to offshore banks. Distribution of "resident" animals during the non-summer period is poorly understood. Use of the study area by "transient" and "offshore" animals does not appear to be predictable however, "transient" animals are often observed in bays, fjords, and shallow coastal areas, while "offshore" animals are found near offshore banks such as La Perouse Bank (G. Ellis, pers. comm.; J. Darling pers. comm.).

Killer Whales are the largest member of the dolphin family. They habituate the upper layers of the cooler coastal seas and occasionally tropical seas. Although they have been observed feeding on penguins, seals, porpoises and Baleen Whales, their reputation for doing this is probably exaggerated. They primarily feed upon fish, such as salmon and cod, and squid. Large concentrations of Killer Whales are usually found over the Continental Shelf where they prefer the deep water. Sightings within the surf zone, although not as common, include shallow bays, inland seas and estuaries. Whales are characterised according to movement. A "transient" group tends to form smaller pods of 1 to 7 animals, that roam over a wider area and feed predominantly on marine mammals, vocalise less frequently, make abrupt changes in swimming direction, and often stay under water for 5 to 15 minutes at a time. They also have a more pointed and centrally positioned dorsal fin. "Resident" pods on the other hand, form larger pods ranging from 5 to 25 animals, have smaller home ranges, feed mainly on fish and vocalise frequently. They also keep to predictable swimming routes, and rarely stay underwater for more than 4 minutes at a time.