Abstract
Stomach contents were identified from 206 Antarctic starry skate (Amblyraja georgiana) that were collected during three groundfish surveys (September 2007, April 2008 and January 2009) at South Georgia, Southern Ocean. The diet of A. georgiana varied with skate size and between years. Preferred prey included fish (particularly for larger individuals) and Antarctic krill, Euphausia superba, as well as amphipods, polychaetes and other benthic fauna. The skate A. georgiana appears to be an opportunistic predator, and the clear presence of Antarctic krill in this demersal predator’s diet may indicate a benthic habit of this euphausiid species, which has hitherto mainly been considered as occupying a purely pelagic niche.
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Acknowledgments
We would like to thank the scientists and crew working on the three surveys and Helena Wiklund and Mike Thurston for help with the identification of polychaetes and amphipods, respectively. Thanks also to Katrin Schmidt for some constructive comments on the manuscript and Alex Brown for some help with graphics. This work contributed to the British Antarctic Survey Discovery 2010 project.
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Main, C.E., Collins, M.A. Diet of the Antarctic starry skate Amblyraja georgiana (Rajidae, Chondrichthyes) at South Georgia (Southern Ocean). Polar Biol 34, 389–396 (2011). https://doi.org/10.1007/s00300-010-0894-9
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DOI: https://doi.org/10.1007/s00300-010-0894-9