Fin Whale

Second only to the blue whale in size, the fin whale (Balaenoptera physalus) can reach a maximum length of 80 ft, and a reported weight of 75 tons. Finners are less robust than blues, and they are considerably faster and more graceful. The fin whale is a rorqual (i.e., a member of the Balaenopteridae family) and gets its common name from its falcate dorsal fin, which may be 2 ft high, and is much larger and further forward than that of the blue whale. (The name "rorqual" is derived from the Norwegian rorhval, which means "grooved whale.") The tall, hooked dorsal provides an easy way to differentiate the fin whale from the blue whale at the surface, and where a blue whale looks bluish in the water, the fin whale is definitely gray, often tending toward brown. Unlike the blue whale, which usually shows a curved back and then the relatively tiny dorsal fin, the fin whale's blowhole often appears concurrently with a flattened expanse of back and the tall dorsal fin. Finners, also known as "razorbacks" for the sharply defined caudal peduncle, are among the fastest whales, having been clocked at 25 mph. Their lower jaws are black on the left side and white on the left, making them the only consistently asymmetrically colored animals in the world. Moreover, the baleen plates on the forward part of the mouth match the coloration of the jaws: black on the left and white on the right. In addition to its striking asymmetry, the fin whale is also decorated with a pattern of swoops and swirls, where the darker coloration on the left side seems to flow from a black band that originates behind the right eye and arches over the whale's right shoulder behind the blowhole until it blends with the uniform dark gray coloring on the animal's left side. There are also some pale streaks, one of which emanates from the right ear hole, and a more or less symmetrical V-shaped mark on the back that is referred to as a "chevron." The underside of the fin whale, including the ventral surface of the flippers and flukes, is white. Males and females are similarly colored, and the reason, if there is one, for their curious coloration is unknown. (Fin whales have been seen to turn on either their white or their black side when feeding on schooling fishes.) The ventral pleats, which number about 85, end evenly at the navel. Through examination of ear plugs, where layers are laid down annually, it has been determined that fin whales in the wild can live for up to 90 years, but in the recent past, few individuals were allowed to reach that age unmolested, and ear plug analysis was commonly employed as a tool to determine how old the animal was when the whalers killed it. Fin whales are born at about 21 ft in length, and weigh about 2 tons. The young are weaned at 6 or 7 months when they are 36-39 ft in length. Weaned calves travel with their mothers to the winter feeding grounds. Females probably reach sexual maturity between 6 and 12 years of age and will reproduce every 2 or 3 years thereafter. Full physical maturity is not attained until between 25 and 30 years. Fin whales are found throughout the temperate and subpolar waters of the world, and are probably the most common of the large whales. They are opportunistic feeders, feeding on whatever prey item is abundant in a particular area. In Norwegian waters, they prefer small schooling fishes like capelin and herring, but they will also eat krill and other small crustaceans. In the western North Atlantic, they sometimes eat cod, and in Antarctic waters, their primary food item is krill. Feeding fin whales turn on their side and swallow huge mouthfuls of water and prey, greatly distending their throats before forcing the water out through the baleen plates and swallowing the prey items. Fin whales are commonly found in deeper waters, and although they are capable of deep dives, they submerge to depth only if pursued or harpooned, since their prey, especially krill, is usually found within 100 m of the surface.

Fin whales do not echolocate, but emit low-frequency sounds that are probably used for intraspecies communication. As with those of other large baleen whales, fin whale vocalizations are loud, low-frequency (20-100 Hz) sounds. The most common sounds produced by a fin whale are the so-called 20 Hz pulses, which are short- (usually between 0.5-1 s) frequency sweeps, usually down-sweeps, but sometimes constant-frequency calls, upsweeps, or wavers.

No aboriginal hunters in times before Euro-American contact are known to have targeted fin whales, probably due to its size, but they were not averse to utilizing a carcass that had washed ashore. Inuit names for the fin whale include tykyshkok, keporkarnak, vapaklichan, and nitkokkein uiiuit, and the Aleuts refer to it as mangidadakh. Norwegian fin whaling began in 1868 in Varanger Fjord, Finnmark, and lasted until 1904, when a shortage of whales prompted the whalers to seek other fin whale populations in other parts of the North Atlantic. Whaling from Icelandic stations began in 1883, and in the Faroes in 1894. In 1898, modern whaling was introduced to the western North Atlantic, as the Norwegians set up shore stations at Snooks Arm and Hermitage Bay, Newfoundland. The first floating factory was employed off Svalbard in 1903, and a shore station was built in the Hebrides in 1904. In almost all cases, the larger blue whale was the primary target, but as blues became scarcer, the whalers concentrated on the somewhat smaller but far more numerous fin whales.

When the whalers had substantially reduced the blue and fin whale populations of the North Atlantic, they headed south, with the same intentions and the same results. They decimated the blue whale population of the Antarctic, and then turned their harpoons on the fin whales and killed them in astonishing numbers. For example, in the period between 1946 and 1965, Antarctic whalers killed 417,787 fin whales: an average of 20,889 per year. During this period, fin whales were also being hunted in the North Atlantic and North Pacific, so these numbers are only part of the total. Although their numbers were severely depleted, finners are now protected throughout the world under the US Marine Mammal Protection Act, Convention on International Trade in Endangered Species and IUCN Red List, and commercial whaling banned under the International Whaling Convention. Aboriginal subsistence hunting in Greenland is permitted under the International Whaling Convention.

Richard Ellis

See also Whaling, Historical Further Reading

Aguilar, A., "Fin Whale." In Encyclopedia of Marine Mammals, edited by W.F. Perrin, B. Wursig & J.G.M. Thewissen, London and San Diego: Academic Press, 2002 Ellis, R., The Book of Whales, New York: Knopf, 1980

-, Men and Whales, New York: Knopf, 1991

Gambell, R., "Fin Whale Balaenoptera physalus (Linnaeus 1758)." In Handbook of Marine Mammals, Volume 3, The Sirenians and Baleen Whales, edited by S.H. Ridgway & R. Harrison, New York: Academic Press, 1985, pp. 171-192

Hershkovitz, P., "Catalog of living whales." United States

National Museum Bulletin, 246 (1966): 1-259 Jonsgard, A., "Biology of the North Atlantic fin whale Balaenoptera physalus (L): taxonomy, distribution, migration and food. "Hvalradets Skrifter," 49 (1966): 5-62 Mowat, F., Sea of Slaughter, Atlantic Monthly Press, 1984 T0nnesen, J.N. & A.O. Johnsen, The History of Modern Whaling, London: C. Hurst and Company and Canberra: Australian National University Press, 1982

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