Balaenidae ( //) is a family of whales of the suborder mysticete that contains two living genera. Historically, it is known as the right whale family, as it was thought to contain only species of right whales. Through most of the 20th Century, however, that became a much-debated (and unresolved) topic amongst the scientific community. Finally, in the early 2000s, science reached a definitive conclusion: the bowhead whale, once commonly known as the Greenland right whale, was not in fact a right whale. The family of Balaenids, therefore, comprises the right whales (genus Eubalaena), and in a genus all to its own, the very closely related bowhead whale (genus Balaena).
Balaenids are large whales, with an average adult length of 15 to 17 metres (45-50 feet), and weighing 50-80 tonnes. Their principle distinguishing feature is their narrow, arched, upper jaw, which gives the animals a deeply curved jawline. This shape allows for especially long baleen plates. The animals utilise these by floating at or near the surface, and straining food from the water, which they then scrape off the baleen with their tongues - a feeding method that contrasts with those of the rorquals and the Gray Whale. Their diet consists of small crustaceans, primarily copepods, although some species also eat a significant amount of krill.
Balaenids are also robustly built by comparison with the rorquals, and lack the grooves along the throat that are distinctive of those animals. They have exceptionally large heads in comparison with their bodies, reaching 40% of the total length in the case of the Bowhead Whale. They have short, broad, flippers, and lack a dorsal fin.
All species are at least somewhat migratory, moving into warmer waters during the winter, during which they both mate and give birth. Gestation lasts 10–11 months, results in the birth of a single young, and typically occurs once every three years.
- Family Balaenidae
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- Bannister, John L. (2008). "Baleen Whales (Mysticetes)". In Perrin, W. F.; Wursig, B.; Thewissen, J. G. M.. Encyclopedia of Marine Mammals. Academic Press. p. 80. ISBN 978-0-12-373553-9. http://books.google.com/books?id=2rkHQpToi9sC&pg=PA80. Retrieved 20 May 2012. "Although Rice believed that all right whales belong with the bowhead in the genus Balaena, recent genetic analysis have recognized three separate right whale species, in the genus Eubalaena: in the North Atlantic (E. glacialis); in the North Atlantic (E. japonica); and in the Southern Hemisphere (E. australis)."
- Kenney, Robert D. (2008). "Right Whales (Eubalaena glacialis, E. japonica, and E. australis)". In Perrin, W. F.; Wursig, B.; Thewissen, J. G. M.. Encyclopedia of Marine Mammals. Academic Press. p. 963. ISBN 978-0-12-373553-9. http://books.google.com/books?id=2rkHQpToi9sC&pg=PA963. Retrieved 20 May 2012. "The study by Churchill (2007) now has provided the evidence to conclude that the three living right whale species do comprise a phylogenetic lineage distinct from the bowhead and are rightly classified into a separate genus."
- Gaskin, David E. (1984). Macdonald, D.. ed. The Encyclopedia of Mammals. New York: Facts on File. pp. 230–235. ISBN 0-87196-871-1.
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