Polar Biology

, Volume 35, Issue 8, pp 1197–1208 | Cite as

A missing piece in the Arctic food web puzzle? Stomach contents of Greenland sharks sampled in Svalbard, Norway

  • Lisa-Marie E. Leclerc
  • Christian Lydersen
  • Tore Haug
  • Lutz Bachmann
  • Aaron T. Fisk
  • Kit M. KovacsEmail author
Original Paper


Harbour seals in Svalbard have short longevity, despite being protected from human hunting and having limited terrestrial predation at their haulout sites, low contaminant burdens and no fishery by-catch issues. This led us to explore the diet of Greenland sharks (Somniosus microcephalus) in this region as a potential seal predator. We examined gastrointestinal tracts (GITs) from 45 Greenland sharks in this study. These sharks ranged from 229 to 381 cm in fork length and 136–700 kg in body mass; all were sexually immature. Seal and whale tissues were found in 36.4 and 18.2%, respectively, of the GITs that had contents (n = 33). Based on genetic analyses, the dominant seal prey species was the ringed seal (Pusa hispida); bearded seal (Erignathus barbatus) and hooded seal (Cystophora cristata) tissues were each found in a single shark. The sharks had eaten ringed seal pups and adults based on the presence of lanugo-covered prey (pups) and age determinations based on growth rings on claws (≤1 year and adults). All of the whale tissue was from minke whale (Balenoptera acutorostrata) offal, from animals that had been harvested in the whale fishery near Svalbard. Fish dominated the sharks’ diet, with Atlantic cod (Gadus morhua), Atlantic wolffish (Anarhichas lupus) and haddock (Melanogrammus aeglefinus) being the most important fish species. Circumstantial evidence suggests that these sharks actively prey on seals and fishes, in addition to eating carrion such as the whale tissue. Our study suggests that Greenland sharks may play a significant predatory role in Arctic food webs.


Arctic Diet Pinnipeds Predator Seals Somniosus microcephalus 



We thank G. Christensen, K. Frost, J.I. Karlsen, L. Lowry, H. Lund, B. McMeans, K. Molde, Y. Watanabe and the crew on RV Lance for their help in the field. In addition, we thank B. Bye for help with the map, and P. Haugen, L. Lindblom and B. Santos for help with analyses of the stomach contents, and Christoph Hahn for help in the laboratory with the genetics analyses. This work was funded by the Norwegian Polar Institute and the Norwegian Research Council’s Ocean and Coastal programme.


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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Lisa-Marie E. Leclerc
    • 1
  • Christian Lydersen
    • 1
  • Tore Haug
    • 2
    • 3
  • Lutz Bachmann
    • 4
  • Aaron T. Fisk
    • 5
  • Kit M. Kovacs
    • 1
    Email author
  1. 1.Norwegian Polar InstituteFram CentreTromsøNorway
  2. 2.Department of Arctic and Marine BiologyUniversity of TromsøTromsøNorway
  3. 3.Institute of Marine ResearchTromsøNorway
  4. 4.National Centre for Biosystematics, Natural History MuseumUniversity of OsloBlindern, OsloNorway
  5. 5.University of WindsorWindsorCanada

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