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The North Pacific right whale (''Eubalaena japonica'') is a very large, robust baleen whale species that is now extremely rare and endangered. The Northeast Pacific subpopulation, which summers in the southeastern Bering Sea and Gulf of Alaska, may have no more than 50 animals. A western subpopulation that summers in the Sea of Okhotsk between the Kuril Islands and Sakhalin Island appears to number in the low hundreds of animals. Prior to commercial whaling in the North Pacific (i.e. pre-1835) the populations in the North Pacific probably were over 20,000 animals. The taking of right whales in commercial whaling has been prohibited by one or more international treaties since 1935. Between 1962 and 1968, illegal Soviet whaling killed 529 right whales in the Bering Sea and Gulf of Alaska as well as 132 right whales in the Sea Okhotsk.〔 The International Union for the Conservation of Nature categorizes the species as "Endangered". It categorizes the Northeast Pacific subpopulation as "Critically Endangered".〔Reilly, S.B., Bannister, J.L., Best, P.B., Brown, M., Brownell Jr., R.L., Butterworth, D.S., Clapham, P.J., Cooke, J., Donovan, G.P., Urbán, J. & Zerbini, A.N. 2008. (Eubalaena japonica (Northeast Pacific subpopulation) ). In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.1.〕 According to the Center for Biological Diversity, the North Pacific right whale is the most endangered whale on Earth.〔 (North Pacific right whale ), Center for Biological Diversity.〕 ==Taxonomy== (詳細はbowhead whale of the arctic (''B. mysticetus''), and ''Eubalaena''—the "right whales", also often called "black right whales". Despite a superficial resemblance to the much larger ''Eubalaena'' species, the pygmy right whale (''Caperea marginata'') of the Southern Hemisphere is not closely related, having been recently recognized as the sole living species of the family, Cetotheriidae. Until recently, all right whales of the genus ''Eubalaena'' were considered a single species—''E. glacialis''. In 2000, genetic studies of right whales from the different ocean basins led scientists to conclude that the populations in the North Atlantic, North Pacific and Southern Hemisphere constitute three distinct species which they named: the North Atlantic right whale (''Eubalaena glacialis''), the North Pacific right whale (''Eubalaena japonica'') and the Southern right whale (''Eubalaena australis''). Further genetic analysis in 2005 using mitochondrial DNA and nuclear DNA has supported the conclusion that the three populations should be treated as separate species, and the separation has been adopted for management purposes by the U.S. National Marine Fisheries Service and the International Whaling Commission.〔 The cladogram is a tool for visualizing and comparing the evolutionary relationships between taxa. The point where a node branches off is analogous to an evolutionary branching – the diagram can be read left-to-right, much like a timeline. The following cladogram of the Balaenidae family serves to illustrate the current scientific consensus as to the relationships between the North Pacific right whale and the other members of its family. }} |label2= ''Balaena'' (bowhead whales) |2= ''B. mysticetus'' bowhead whale }} }} }} 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「North Pacific right whale」の詳細全文を読む スポンサード リンク
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