Whalebone Whales
Whalebone Whales
(Mysticeti), a suborder of mammals of the order Cetacea. They have no teeth; in their place, in the upper jaw there are from 360 to 800 long (20–450 cm), horny plates called whalebone (hence the name). These plates are located across the gums one behind the other at intervals of 0.3–1.2 cm and restrict the mouth cavity from the sides. The interior portion and the top of each plate are split into long, thin bristles that are similar to a thick sieve, or filter, which filter plankton mollusks, crustaceans, and small fish from the water. On the snout there are single hairs, or vibrissae, which serve as sensory organs. The nostrils are paired. Mysticeti are the largest living mammals; the blue whale reaches a length of 33 m and a weight of 160 tons.
The suborder Mysticeti comprises ten species: Greenland, southern right, pygmy right, gray, humpback, blue, finhead, sei, little piked, and Bryde’s whale. Mysticeti are widely distributed in the oceans: the exceptions are the Greenland whale, which lives only in arctic waters; Bryde’s whale, which lives in the warm belt of the world’s oceans; and the pygmy right whale, which lives in the temperate and cold waters of the southern hemisphere.
Whalebone whales are of great commercial significance, as they yield an enormous quantity of oil; the flesh is of less importance. Whaling is conducted by special large ships (“mother ships”) which are the base for small whaleboats. As a result of predatory fishing in the North Atlantic Ocean, whalebone whales were practically annihilated. The fishermen moved to the Pacific Ocean and the seas of the southern hemisphere, as a result of which the general number of all species of Mysticeti in the Antarctic and the northern part of the Pacific Ocean were likewise sharply reduced. Since 1959 international controls have protected the Greenland whale, the southern whale, and the gray whale; the blue whale came under protection in 1967, since there were fewer than 1,000 left in the Antarctic. As a result of conservation measures, the number of blue whales in the Bering Sea has increased slightly, and individual Greenland whales and southern whales have appeared in the northern parts of the Pacific and Atlantic oceans. The finhead and the sei whale have become the primary objects of commercial fishing, and their numbers have likewise begun to decline sharply.
REFERENCES
Tomilin, A. G. Kitoobraznye. Moscow, 1957. (Zveri SSSR i prilezhashchikh strati, vol. 9.)Morskie mlekopitaiushchie. Moscow, 1965. [A collection of articles.]
Morskie mlekopitaiushchie. Moscow, 1969.