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Mammalian Species DISCLAIMER 
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Right Whale (Eubalaena glacialis)
This whale was given its English vernacular name by whalers who considered it the preferred quarry. It was the right whale to hunt because of the relative ease with which it could be taken and its high yield of valuable products, notably oil and whalebone (baleen). Right whales formerly occurred worldwide between cold temperate and subtropical latitudes. Over hunting caused them to disappear from some areas and to become very rare in others. Today there are only a few thousand right whales worldwide, most of them in the Southern Hemisphere. No more than a few hundred survive in the western North Atlantic, and the present population in the eastern North Pacific is believed to number less than 100. Right whales are robust animals, whose girth can be more than 4/5 the body length. Large females reach lengths of 18 m and weights of 100 t or more; males are somewhat smaller. The head comprises up to one-third of the body length. There is no dorsal fin or ridge. The flippers are broad and up to 1.7 m long. The flukes, up to 6 m wide, tip to tip, have a deeply-notched rear margin. The right whale's narrow, curved rostrum (top of the head) is enfolded on either side by the massive lower lips, which are usually scalloped along their upper edges. Patches of cornified skin, called callosities, occur on certain parts of the head. There is always a relatively large callosity, or network of callosities, on the rostrum. Callosities also occur on the chin, around the blowholes, and above the eyes. Most callosities are colonized by large numbers of white, yellow, orange, or pinkish "whale lice" (cyamid crustaceans). Since each right whale has a distinctive arrangement of callosities, these structures are carefully photographed by researchers and used to identify and recognize individual whales. Right whales are basically dark gray or black, although piebald individuals are not unusual. White patches on the ventral surface are common and can cover the entire throat region and much of the belly. Except for the callosities, the skin of right whales is relatively free of ectoparasites. Although frequently described as being heavily infested with barnacles, right whales in the Northern Hemisphere usually carry fewer barnacles than do gray whales and humpbacks. Right whales have considerably longer baleen (up to 2.7 m) than any other species except the bowhead. There are about 230-250 dark gray, finely-fringed plates per side. Right whale baleen is supple, a quality which made it valuable in the manufacture of such things as skirt hoops, buggy whips, and parasols - it was the "spring-steel" of its time. At least 600 kg of baleen could be extracted from a large right whale. There is a gap at the front of the mouth between the two rows of baleen. As the whale feeds with its mouth partially open, seawater streams through this gap and passes out through the fringes of baleen, leaving behind the small organisms trapped against the screen of baleen. Small crustaceans, principally copepods and euphausiids, form the diet of right whales. There is no evidence that they eat fish. Right whales have a distinctly V-shaped blow. They sometimes spend long periods lying motionless at the surface, with only the broad back and blowholes exposed. At other times, they lobtail or flipper. Right whales breach occasionally, propelling their entire bodies clear of the water. These whales are slow swimmers. When chased, they can achieve speeds of close to 20 km per hour for short periods, but they seldom move faster than about 5-10 km per hour. Right whales were formerly abundant in Canadian waters. However, their migrations are poorly understood. In the eastern North Pacific, right whales occur in winter as far south as Baja California and Hawaii; in summer, as far north as the Gulf of Alaska and Bering Sea. In other parts of the world, sheltered embayment serve as winter nurseries for females with calves; but off the west coast of North America, no such nursery areas have been identified. A major nineteenth century whaling ground, called the Kodiak Ground, extended from Vancouver Island across the Gulf of Alaska to the Aleutian Islands. Right whales were caught there mostly from May through July. In the western North Atlantic, the right whale's winter range is between Cape Cod and Florida. At least a part of the population migrates north in spring, reaching the Bay of Fundy and Scotian Shelf during summer and fall. Formerly, right whales were present during summer east of the Grand Banks, in much of the Gulf of St. Lawrence and Strait of Belle Isle, and along the outer coasts of Newfoundland and Labrador. During recent years the lower Bay of Fundy has become recognized as a feeding ground for right whales in summer and autumn. The area of Browns Bank (60 km south of Cape Sable, NS) and the vicinity of Grand Manan Island (NB) are visited by a population of approximately 200 right whales. Females and calves tend to congregate inshore beginning in July. Throughout the rest of summer and well into October, they can be observed in Head Harbour Passage and Grand Manan Channel and along the edges of Grand Manan Basin. Dramatic bouts of courtship, sometimes involving seven or eight males clustered around a single female, occur here as well. At the same time, right whales, generally unaccompanied by calves, are present on the Scotian Shelf, especially in or near Roseway Basin between Browns and Baccaro banks. Photo documentation has demonstrated the movement of animals between the summer feeding grounds off southeastern Canada and a winter calving ground off Georgia and Florida in the southeast US. They probably comprise a separate stock from the one on the European side of the North Atlantic, which is believed to be almost extinct. There is little definite information about the life history of right whales. Most calves are born in winter or spring at lengths of 4.5-6.0 m. Lactation continues through the first summer and possibly into the second year after birth. Judging by resightings of known adult females in the South Atlantic and others in the Northwest Atlantic, the mean interval between births is at least 3 years. |
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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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