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The imperial shag (''Phalacrocorax atriceps'') is a black and white cormorant native to many subantarctic islands, the Antarctic Peninsula and southern South America, primarily in rocky coastal regions, but locally also at large inland lakes. It is sometimes placed in the genus ''Leucocarbo'' instead. It is also known as the blue-eyed shag, blue-eyed cormorant and by many other names, and is one of a larger group of cormorants called blue-eyed shags. The taxonomy is very complex, and several subspecies are often considered separate species. ==Taxonomy== The taxonomy is very complex and species-limits within this group remain unresolved. The following are usually considered part of this group: * Imperial shag, ''Phalacrocorax (atriceps) atriceps'', from coastal southern Chile and Argentina. * King cormorant/white-bellied shag, ''Phalacrocorax (atriceps) albiventer'', from the Falkland Islands, and locally in southern Argentina and Chile. * Antarctic shag, ''Phalacrocorax (atriceps) bransfieldensis'', from the Antarctic Peninsula and the South Shetland Islands. * South Georgia shag, ''Phalacrocorax (atriceps) georgianus'', from the South Georgia and the South Sandwich Islands, and South Orkney Islands. * Heard shag, ''Phalacrocorax (atriceps) nivalis'', from Heard Island. * Crozet shag, ''Phalacrocorax (atriceps) melanogenis'', from the Crozet and Prince Edward Islands. * Macquarie shag, ''Phalacrocorax (atriceps) purpurascens'', from Macquarie Island. While some authorities accept all of the above – except ''albiventer'' – as separate species,〔Orta, J. (1992). Phalacrocoracidae (Cormorants) in: del Hoyo, J., Elliott, A., & Sargatal, J. eds. (1992). ''Handbook of the Birds of the World.'' Vol. 1. Ostrich to Ducks. Lynx Edicions, Barcelona. ISBN 84-87334-10-5〕〔Clements, J. F. (2007). ''The Clements Checklist of Birds of the World.'' 6th edition. Christopher Helm. ISBN 978-0-7136-8695-1〕 others consider all as subspecies of a single species (as done in this article). Alternatively, some recognize two species, the white-cheeked ''P. atriceps'' (with subspecies ''bransfieldensis'', ''nivalis'' and ''georgianus'') and the black-cheeked ''P. albiventer'' (with subspecies ''melanogenis'' and ''purpurascens''),〔Dickinson, E. C. eds. (2003). ''Howard and Moore Complete Checklist of the Birds of the World.'' 3d edition. Christopher Helm. ISBN 0-7136-6536-X〕 or it has been suggested that three species should be recognized: ''P. atriceps'' (including ''albiventer''), ''P. georgianus'' (with subspecies ''bransfieldensis'' and ''nivalis''), and ''P. melanogenis'' (with subspecies ''purpurascens'' and possibly ''verrucosus'', though the latter is relatively distinctive, and most consider it a separate species, the Kerguelen shag).〔 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「imperial shag」の詳細全文を読む スポンサード リンク
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