Region: Pacific Ocean
Killer whales talk to each other through a complex variety of whistles, squeaks and whines, made with air trapped in their blowholes. The sounds vary from pod to pod, with each group having its own unique dialect or language. Killer whales can recognize their own pods easily from several miles away based on the distinctive songs. Researchers believe that the more similar the dialects between two pods, the closer they are related. Pods of whales with related dialects are called clans.
Killer whale pods are very vocal when hunting for prey. They use a series of clicking sounds that bounce off fish and other objects in the water. Called echo-location, this natural sonar is useful when searching for food or navigating in murky water, enabling the whales to build an accurate picture of what’s around them.
Native to the waters off southern Vancouver Island, the population of northeast pacific southern resident killer whales is much smaller today than it was even six years ago. Only 89 individual whales were counted in 1998, 83 in 1999, 82 in 2000 and 78 in 2001—representing a 20 percent decline.
The largest members of the dolphin family, killer whales are highly social animals that live in stable, family-related groups called pods. The family groups—which are led by females—usually consist of five to 50 whales, although sometimes pods can combine to form groups of 100 or more. Like humans, killer whales are very protective of their young and various pod members, including mothers, care for young calves. In the wild, male killer whales live for an average of 17 years and females an average of 29 years.
Killer whales eat a wide range of prey, including squid, fish, sea turtles, sea birds, sea and river otters, sea lions, penguins, dolphins and other large cetaceans, such as the blue whale. Southern resident killer whales, however, eat mainly fish.
The killer whale’s size—seven to nine metres long and between four and five tones in weight—striking black-and-white colouring, and long, rounded body makes it unmistakable. The first sight of a killer whale is often the tall dorsal fin. In fully grown males, this fin sticks straight up, often as high as 1.8 metres. In females and young whales, the fin is curved and less than one metre high. Behind the dorsal fin is a grey area called a saddle patch. The shape of the dorsal fin and saddle patch, as well as natural nicks and scars on them, are unique to each killer whale.
Killer whales are found in all three of Canada’s oceans, and occasionally in Hudson Bay and the Gulf of St. Lawrence. Resident killer whales live in separate northern and southern communities. The northern community lives off northern Vancouver Island and the mainland coast as far north as southeast Alaska. Southern residents are found off southern Vancouver Island.
Recent studies have found that southern-resident killer whales are contaminated with high levels of toxic chemicals such as organochlorine, making them susceptible to disease and reproductive difficulties. Water pollution also affects species on which the whales feed, leading to reduced food supply. The proximity of the whales’ habitat to large urban centers such as Seattle, Victoria and Vancouver has led to more frequent collisions with boats and exposure to significantly higher numbers of oil spills. It’s also possible that the large and growing recreational whale-watching industry may be having a negative impact. Among natural factors that threaten the survival of killer whales are mass strandings.
Legislation to protect killer whale populations in BC waters was first introduced in 1970 under British Columbia’s Wildlife Act. In 1982, the whales were included in regulations under the Fisheries Act of Canada. These regulations prohibit hunting without a license, except for Aboriginal hunting. No licenses are currently being issued. Whale-watching guidelines have also been introduced to minimize negative interactions between boats and whales.
A Recovery Strategy for the Northern and Southern Resident killer whale has been finalized.
Read About : Killer Whales Serve as Sentinels for Ocean Pollution
Killer whales will get the protection they need only if all Canadians work together to reduce threats. Find out more about killer whales and be aware of man-made threats to northern resident killer whales such as entanglement in fishing gear, noise and water pollution, and collision with boats. Do your best to reduce these threats wherever possible to better protect the whales’ critical habitat. Get involved with the Habitat Stewardship Program for Species at Risk (HSP) or another conservation organization.
Join a stewardship program such as the B.C. Cetacean Sightings Network. The Network’s main goals are to identify key habitats and help reduce threats. The Network also solicits cetacean sighting reports from mariners along British Columbia’s coast. Find out more >>.
Or, join the British Columbia Adopt a Killer Whale Adoption program, run in conjunction with the Vancouver Aquarium. Find out more >>.
Background information provided by Environment Canada in March 2004.