Communities of killer whales. Canadian biologists track family pods in Northwest waters
Nanaimo, British Columbia
`IT was just amazing,'' said marine biologist Michael A. Biggs, describing a whale-spotting expedition recently with Britain's Prince Philip. The two, and an assortment of other guests, were on a boat off Victoria, 70 miles south of here. Dr. Biggs was telling the Prince about the ``K1 Pod'' of killer whales that inhabit Haro Strait.
At that moment, a number of whales appeared. Biggs, who knows by sight each of the 300 or so killer whales that roam the waters off British Columbia and Washington State, was able to identify individuals in the pod for the Duke of Edinburgh. One whale, right before them, ate a fish - its usual food. Another rolled over and displayed its entire body, perhaps 25 feet long. Boat and whales traveled together through the water for 20 minutes. The Prince snapped away with a tiny camera.
Biggs heads a group studying marine mammals at the Pacific Biological Station here, a research facility belonging to the Canadian Department of Fisheries and Oceans.
Concerned about the netting of whales to capture them live for aquariums, the group enlisted the help of the public in a count of the whales, starting in 1971. Questionnaires were sent to lighthouses, ferries, fishery patrol boats, tugs, fishermen, and others who lived and worked along the coast of British Columbia. After three such censuses, the number of whales estimated was 200 to 350, much lower than had been thought.
Over time, the process of whale identification was refined. Biggs and his colleagues spent thousands of hours watching the creatures in the ocean. They were able to put together a genealogy for the majority of the whales of the coast, which they call ``residents.''
``There isn't any other study of marine animals where it is possible to do the lineages,'' Biggs said.
He and three other scientists (Graeme M. Ellis, John K. B. Ford, and Kenneth C. Balcomb) have just written a book, ``Killer Whales'' (Phantom Press & Publishers Inc., Nanaimo, British Columbia). Half the book consists of photographs of the left side of the dorsal fins and the saddle patch of all the whales in the area. Each animal can be identified by the unique shape, size, and scars of the fin, and the shape and pigmentation details of the saddle patch behind the fin.
Biggs and his colleagues found that there are two races of killer whales: residents and transients.
The residents are more numerous, living in two ``communities.'' The range of the northern community, composed of 16 pods with a total of 172 whales, extends from about mid-Vancouver Island north to the southeastern tip of Alaska. The southern community, with three pods and 81 whales, ranges from the southern edge of the northern community into Puget Sound, around southern Vancouver Island, and down the west coast of Washington State to about Grays Harbor.
Resident whales feed on fish and squid. Apparently their large pods give them a better chance of locating and corralling their food. Swimming as a group, they cover a wider territory and are more likely to run across a school of fish. After telling one another of a find with ``vocalizations,'' the pod can surround the school in a way that gives them a better chance of catching more fish. In summer and fall, the whales are often found in inshore waters, where salmon congregate before moving upstream to spawn.
Biggs dubs the other race transients because they are more rare, and their movements are far less predictable. These whales normally eat other sea mammals - seals, sea lions, porpoises, and baleen whales.
Transients hunt alone or in small pods, poking into small bays, traveling in near-silence, perhaps so as not to warn prey of their presence. Unlike sharks, killer whales are cautious hunters, sometimes spending hours harassing a 1,000-pound sea lion until the tusk-bearing creature is so tired it can be drowned safely. These transients will dive for five to 10 minutes, while the residents tend to stay down only a few minutes or less.
``They pose virtually no danger to humans,'' says Biggs. They are considered benevolent to man, even in the folklore of the Indians who lived on this coast for thousands of years before the arrival of Europeans.
Biggs has never seen any sign of aggression during his many hours in a boat among the whales. ``They are extremely tolerant animals,'' he says.
The two races apparently do not mate. Neither do they travel together or show any signs of aggression toward each other. Referring to their different feeding habits, travel patterns, pod sizes, and vocalizations, Biggs speaks of ``cultural'' differences. Further, the physical appearance of the dorsal fin often differs in the two races.
Among other findings about killer whales:
They live in a matriarchal society. In the case of resident whales, children of all ages generally travel close to their mothers throughout their lives. One pod of resident whales may include a grandmother, her daughters and sons, and her grandchildren. It is this characteristic that enabled Biggs and his colleagues to develop almost complete genealogies for the resident whales. Unlike residents, some transient whales leave their mothers when they mature. So the biologists were able to draw up only limited genealogies for the transients.
The life span of these whales is similar to that of human beings. Females live 70 or 80 years, and males 50 or 60 years. Females start to bear calves in their mid-teens. These newborns are about eight feet long and weigh about 400 pounds. A typical female will bear four to six offspring over a 25-year period and then stop breeding. They give birth mainly in fall and winter, though births can occur at any time of year. Males reach a maximum of about 32 feet long and 10 to 11 tons; females, 28 feet and 7 to 8 tons. Adult males can be distinguished by their tall dorsal fins, which can reach 5 feet. Female dorsal fins reach only about 3 feet.
Both resident and transient killer whales produce two types of underwater vocalization. One consists of a series of as many as several hundred brief, high-energy clicks per second. These are probably for echolocation, helping the whale to navigate and locate prey. The other, used for communication, consists of ``whistles, variable calls, and discrete calls.'' Whistles and variable calls seem to be used when whales are socializing in a tightly knit group.
Killer whales have been protected in British Columbia since 1970. ``People still shoot them, though,'' laments Biggs. Netting of killer whales to catch them for aquariums stopped in the mid-1970s in British Columbia and Washington State because of public opposition. That combined protection has enabled the west coast population to grow at a rate of about 2 percent a year.
That pleases Biggs. ``These are magnificent animals,'' he says.