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Polar Biology

, Volume 33, Issue 11, pp 1537–1546 | Cite as

The diet of the Imperial Shag Phalacrocorax atriceps at a colony on New Island, Falkland/Malvinas Islands combining different sampling techniques

  • Andreas MichalikEmail author
  • Hendrika J. van Noordwijk
  • Paul Brickle
  • Till Eggers
  • Petra Quillfeldt
Original Paper

Abstract

The diet of the Imperial Shag Phalacrocorax atriceps was studied on New Island, Falkland/Malvinas Islands during the 2008/2009 breeding season, with some additional data from 2007/2008. The diet comprised a large variety of prey, mainly fish, crustaceans and squid. In contrast to other species of the blue-eyed shag complex, prey not only consisted of benthic organisms but also included pelagic prey. Different sampling techniques were combined in order to obtain a comprehensive overview of the diet. Pellets, regurgitations and stomach contents yielded different results. We discuss the causes for these variations including different sample availability over time. In particular, the stomach analyses seem to overestimate the importance of squid based on the occurrence of squid beaks. For the pellet analyses, lobster krill accounted for the majority of the prey remains except during the second half of December (i.e. when young chicks were being attended), when fish was more important.

Keywords

Imperial Cormorant Diet Stomach content Regurgitation Pellet Falkland/Malvinas Islands 

Notes

Acknowledgments

We are grateful to the New Island Conservation Trust, Ian, Maria and Georgina Strange and Dan Birch who facilitated fieldwork. We wish to thank Alexander Arkhipkin, Gritta Veit-Köhler, Günter Purschke, Wiebke Brökeland and Charles Oliver Coleman for help in identification of prey remains. Financial support for fieldwork came from DFG-German Research Foundation, Germany (Qu 148/1-ff) and DAAD—the German Academic Exchange Service. Fieldwork at New Island was approved and co-funded by the Falkland Islands Government (Environmental Planning Office).

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Andreas Michalik
    • 1
    • 2
    Email author
  • Hendrika J. van Noordwijk
    • 1
  • Paul Brickle
    • 3
  • Till Eggers
    • 2
  • Petra Quillfeldt
    • 1
  1. 1.Max-Planck-Institut für OrnithologieRadolfzellGermany
  2. 2.Department of Biology/Chemistry, Experimental Ecology GroupUniversity of OsnabrückOsnabrückGermany
  3. 3.Fisheries DepartmentFalkland Islands GovernmentStanleyFalkland Islands

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