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The graytail skate or gray tail skate (''Bathyraja griseocauda'') is a large species of skate in the family Arhynchobatidae, native to the southwest Atlantic ocean and southeast Pacific ocean. It is listed as endangered by the IUCN.〔 It was caught as part of a commercial fishery around the Falkland Islands and is a bycatch in several other fisheries. == Range and distribution == In the Atlantic ocean, the graytail skate is found off the coast of Argentina and in the waters surrounding the Faulkland Islands. The northern extent of its range in the Atlantic is 37 degrees South.〔 Its range extends very slightly past Cape Horn into the Pacific ocean, off the coast of Chile, but does not extend beyond a northern extent of 41 degrees South.〔 Although graytail skates have been found in waters as shallow as , they are most often found deeper than . They are found all over the continental shelf surrounding the Falkland Islands, but are found in highest concentration in the western, deeper shelf margin. Individuals also segregate spatially by age class. Nursery grounds near the Falkland Islands are generally located at depths of 300-350m. Juveniles are found in deeper water, , but migrate either to the upper slope () or into deeper water (below ) after growing to in length.〔 The current population size of the graytail skate is not known.〔 However the catch per unit effort has declined from 1993-2001,〔 as well as a decrease in size.〔 These indicators led to the partial closure of the fishery around the Falklands, although no assessments have been completed to gauge current status. The frequency of bycatch and slow growth rate have led fisheries scientists to believe the fisheries restriction has not reversed the decline.〔 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「Graytail skate」の詳細全文を読む スポンサード リンク
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