Polar Biology

, Volume 30, Issue 2, pp 167–181 | Cite as

Feeding ecology of phocid seals and some walrus in the Alaskan and Canadian Arctic as determined by stomach contents and stable isotope analysis

  • Larissa-A. Dehn
  • Gay G. Sheffield
  • Erich H. Follmann
  • Lawrence K. Duffy
  • Dana L. Thomas
  • Todd M. O’Hara
Original Paper


Feeding habits of ringed (Phoca hispida), bearded (Erignathus barbatus), spotted (Phoca largha) and ribbon (Phoca fasciata) seals and walrus (Odobenus rosmarus) were studied using stomach contents and stable carbon and nitrogen isotopes. Bearded seals fed benthically, primarily crustaceans and mollusks. Both zooplankton and fish were significant prey for ringed seals, while fish was principal spotted seal prey. Few gastric contents were available from ribbon seals. δ15N was positively correlated with age in ribbon seals and δ13C was positively correlated with age in ringed and ribbon seals. δ15N was highest in spotted seals, in agreement with their fish-dominated diet. δ15N was not different between Alaskan-harvested ringed and bearded seals, while δ15N was lowest in ribbon seals and walrus. Carbon-13 was most enriched in bearded seals and walrus reflecting benthic ecosystem use. Canadian ringed seals were depleted in 13C compared to Alaskan pinnipeds, likely because of Beaufort Sea versus Chukchi and Bering seas influence.


Stomach Content Ringed Seal Harbor Seal Stomach Content Analysis Nitrogen Isotope Ratio 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This study would not have been possible without the samples provided by Alaskan and Canadian subsistence hunters in the communities of Barrow, Holman, Little Diomede and Shishmaref, and we thank them all for their support. We greatly appreciate the assistance of C. D. N. Brower, H. Brower Jr., T. Olemaun, B. Akootchook, T. Hepa, L. Hopson, V. Woshner, R. Elsner, T. Zenteno-Savin, S. Visalli, D. Burnett, G. York and many others in the field and T. Bentzen, T. Howe, N. Haubenstock and P. Hoekstra for support with analysis. We also thank L. Harwood for providing tissues and jaws of ringed seals harvested in Holman, R. Highsmith and B. Bluhm for collection of amphipod samples from the Bering Strait, and J. Bengtson and D. DeMaster for training in cementum aging and stomach contents analysis. The Frozen Tissue Collection of the University of Alaska Museum provided some of the spotted seal muscle samples. The comments of two anonymous reviewers improved the manuscript.

This study was primarily funded by the Cooperative Institute for Arctic Research. Additional support was provided by the Experimental Program for Stimulation of Competitive Research; the North Slope Borough Department of Wildlife Management; the Institute of Arctic Biology and the Department of Biology and Wildlife, UAF; the US Geological Survey; the Barrow Arctic Science Consortium; and the National Science Foundation OPP Grant 9910319.


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Larissa-A. Dehn
    • 1
  • Gay G. Sheffield
    • 2
  • Erich H. Follmann
    • 1
  • Lawrence K. Duffy
    • 1
  • Dana L. Thomas
    • 3
  • Todd M. O’Hara
    • 1
    • 4
  1. 1.Institute of Arctic BiologyUniversity of Alaska FairbanksFairbanksUSA
  2. 2.Alaska Department of Fish and Game, FairbanksDivision of Wildlife ConservationFairbanksUSA
  3. 3.Department of Mathematics and StatisticsUniversity of Alaska FairbanksFairbanksUSA
  4. 4.Department of Wildlife ManagementNorth Slope BoroughBarrowUSA

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