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Mammalian Species DISCLAIMER 
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Fin Whale (Balaenoptera physalus)
The fin whale, second in size only to the blue whale, has a wider distribution and is considerably more abundant than its larger relative. Groups of fin whales, sometimes numbering up to 20 individuals, were historically common in coastal and inshore waters at temperate latitudes. Decades of intensive exploitation have greatly reduced most fin whale populations, but these large, fast swimming animals are still a common sight in Canadian coastal waters. Fin whales range widely in the North Atlantic, from the Mediterranean Sea to Norway in the east and from Florida to Davis Strait in the west. They are abundant around Iceland and off the east and west coasts of Greenland. In the North Pacific, fin whales occur from the Chukchi Sea in the north, south to the Gulf of California in the east and Japan in the west. They have also been reported from the mid-Pacific. It is difficult for an inexperienced observer to distinguish between the fin whale and the sei whale. The fin whale's asymmetric head colouration is its most reliable and least subtle field mark. The right lower jaw and eight front third of the baleen are white; the rest of the head and baleen, darker. Behavioural differences can also help in making an identification. The fin whale has a characteristic roll. The head usually breaks the surface first, and the animal blows just before the dorsal fin appears. The fin whale usually arches its back high out of the water on the terminal dive of a series, but it almost never flukes-up. The sei whale usually approaches the surface at a flatter angle, and its prominent dorsal fin can sometimes be seen while the whale is blowing. Sei whales usually do not arch the back high as they dive. Fin whales have a varied diet. In some areas or at certain times of year, they feed heavily on pelagic crustaceans, mainly euphausiids but also copepods occasionally. In other areas or at other times, small schooling fishes such as capelin, herring, sand lance, and anchovies are the staple fare. Cod, whiting, mackerel, and squid are sometimes eaten. Tagging data and morphological differences suggest the existence of at least two separate populations of fin whales off eastern Canada, one of which summers on the Scotian Shelf and in the Gulf of St. Lawrence, and the other in the Labrador Sea. There may be a small degree of mixing between these two populations. Fin whales share much of the same habitat with blue whales in the St. Lawrence, arriving in large numbers by July and feeding along the North Shore throughout summer and fall. They also are regularly seen in the lower Bay of Fundy, where they sometimes enter and damage inshore herring weirs. In British Columbia, fin whales are usually found well offshore but are sometimes seen in exposed coastal seas such as Hecate Strait and Queen Charlotte Sound, and less often in protected waters such as Queen Charlotte Strait. Some fin whales, mainly young individuals, remain to feed throughout the summer. Others migrate past the British Columbia coast. Because of their large size and ready availability, fin whales figured significantly in the catches of all modern Canadian shore whaling stations. Beginning with the 1967 season, a Canadian national quota was set on fin whales hunted from the east coast whaling stations. As additional information became available on stock identity and population size, this quota was steadily lowered. Canada's east coast fin whale population has been unexploited since 1972. |
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SOURCE: Communications Directorate Department of Fisheries and Oceans Ottawa, Ontario K1A 0E6 © Minister of Supply and Services, Canada Cat. No.: Fs 41-33/59-1988E ISBN: 0-662-16501-2 Reprinted 1993 |
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