Polar Biology

, Volume 33, Issue 8, pp 1149–1153 | Cite as

Has early ice clearance increased predation on breeding birds by polar bears?

  • Paul A. Smith
  • Kyle H. Elliott
  • Anthony J. Gaston
  • H. Grant Gilchrist
Short Note


Past studies suggest that polar bears (Ursus maritimus) consume terrestrial food only opportunistically and derive little nutritional benefit from it. Here, we present observations of at least 6 bears consuming large numbers of snow goose (Chen caerulescens) eggs at two locations in the eastern low Arctic in 2004 and 2006. We also report two records of a polar bear eating the eggs and chicks of cliff-nesting thick-billed murres (Uria lomvia) in 2000 and 2003. Climatic warming has resulted in progressively earlier ice break-up in Hudson Bay, forcing bears ashore much earlier than historical records indicate. Advancement in the nesting dates of birds has been more modest, and this mismatch in timing could lead to an increasing overlap between the nesting period of birds and the period during which bears are on land. At these sites in these years, bears were on land prior to the hatch of nests, and the predation that ensued was catastrophic for the birds at a local scale. Although anecdotal, our observations highlight the complexity of trophic interactions that may occur in a changing Arctic.


Polar bear Ursus maritimus Snow goose Chen caerulescens Climatic change Thick-billed murre Uria lomvia Predation 



Field work at all sites was funded by Environment Canada, and logistical support provided by the Polar Continental Shelf Project. We appreciated the helpful comments provided by A. Tarroux, D. Berteaux, G. Donaldson and one anonymous reviewer.


  1. Berteaux D, Réale D, McAdam AD, Boutin S (2004) Keeping pace with fast climate change: can arctic life count on evolution? Integrat Comp Biol 44:140–151CrossRefGoogle Scholar
  2. Cooke F, Rockwell RF, Lank DB (1995) The Snow Geese of La Pérouse Bay: natural selection in the wild. Oxford University Press, OxfordGoogle Scholar
  3. Derocher AE, Andriashek D, Stirling I (1993) Terrestrial foraging by polar bears during the ice-free period in Western Hudson Bay. Arctic 46:251–254Google Scholar
  4. Donaldson GM, Chapdelaine G, Andrews JD (1995) Predation of thick-billed murres, Uria lomvia, at two breeding colonies by polar bears, Ursus maritimus, and walruses, Odobenus rosmarus. Can Field-Nat 109:112–114Google Scholar
  5. Drent RH, Prop J (2008) Barnacle goose Branta luecopsis survey on Nordenskiöldkysten, west Spitsbergen 1975–2007: breeding in relation to carrying capacity and predator impact. In: Hacquebord L, Boschman N (eds) A passion for the pole: ethological research in polar regions. Barkhuis Publishing, GroningenGoogle Scholar
  6. Gaston AJ, Hipfner JM (2000) The thick-billed murre (Uria lomvia). In: Poole A, Gill F (eds) The birds of North America No. 497. The Birds of North America, Inc., PhiladelphiaGoogle Scholar
  7. Gaston AJ, Ouellet H (1997) Birds and mammals of Coats Island. NWT Arctic 50:101–118Google Scholar
  8. Gaston AJ, Gilchrist HG, Hipfner JM (2005) Climate change, ice conditions and reproduction in an Arctic nesting marine bird: the thick-billed murre (Uria lomvia L.). J Anim Ecol 74:832–841CrossRefGoogle Scholar
  9. Gaston AJ, Gilchrist HG, Mallory ML, Smith PA (2009) Changes in seasonal events, peak food availability and consequent breeding adjustment in a marine bird: a case of progressive mis-matching. Condor 111:111–119CrossRefGoogle Scholar
  10. Gauthier G, Bêty J, Giroux JF, Rochefort L (2004) Trophic interactions in a High Arctic Snow Goose colony. Integrat Comp Biol 44:119–129CrossRefGoogle Scholar
  11. Gough WA, Cornwell AR, Tsuji LJS (2004) Trends in seasonal sea-ice duration in southwestern Hudson Bay. Arctic 57:298–304Google Scholar
  12. Hobson KA, Stirling I, Andriashek DS (2009) Isotopic homogeneity of breath CO2 from fasting and berry-eating polar bears: implications for tracing reliance on terrestrial foods in a changing Arctic. Can J Zool 87:50–55CrossRefGoogle Scholar
  13. Lowry LF, Burns JJ, Nelson RR (1987) Polar bear, Ursus maritimus, predation on belugas, Delphinapterus leucas, in the Bering and Chukchi Seas. Can Field-Nat 101:141–146Google Scholar
  14. Mallory ML, Gaston AJ, Gilchrist HG (2009) Sources of breeding season mortality in Canadian Arctic seabirds. Arctic 62:333–341Google Scholar
  15. Mowbray TB, Cooke F, Ganter B (2000) Snow Goose (Chen caerulescens). In: Poole A, Gill F (eds) The birds of North America No. 514. The Birds of North America, Inc., PhiladelphiaGoogle Scholar
  16. Obbard ME, Cattet MRL, Moody T, Walton LR, Potter D, Inglis J, Chenier C (2006) Temporal trends in the body condition of southern Hudson Bay polar bears. Climate Change Research Information Note 3, Ontario Ministry of Natural ResourcesGoogle Scholar
  17. Post E, Forchhammer MC, Bret-Harte S, Callaghan TV, Christensen TR, Elberling B, Fox AD, Gilg O, Hik DS, Høye TT, Ims RA, Jeppesen E, Klein DR, Madsen J, McGuire AD, Rysgaard S, Schindler DE, Stirling I, Tamstorf MP, Tyler NJC, van der Wal R, Welker J, Wookey PA, Schmidt NM, Aastrup P (2009) Ecological dynamics across the arctic associated with recent climate change. Science 235:1355–1358CrossRefGoogle Scholar
  18. Ramsay MA, Hobson KA (1991) Polar bears make little use of terrestrial food webs: evidence from stable-carbon isotope analysis. Oecologia 86:598–600CrossRefGoogle Scholar
  19. Rockwell RF, Gormezano LJ (2009) The early bear gets the goose: climate change, polar bears and lesser snow geese in western Hudson Bay. Polar Biol 32:539–547CrossRefGoogle Scholar
  20. Russell RH (1975) The food habits of polar bears of James Bay and southwest Hudson Bay in summer and autumn. Arctic 28:117–129Google Scholar
  21. Schliebe S, Rode KD, Gleason JS, Wilder J, Proffitt K, Evans TJ, Miller S (2008) Effects of sea ice extent and food availability on spatial and temporal distribution of polar bears during the fall open-water period in the Southern Beaufort Sea. Polar Biol 31:999–1010CrossRefGoogle Scholar
  22. Skinner WR, Jeffries RL, Carleton TJ, Rockwell RF, Abraham KF (1998) Prediction of reproductive success and failure in lesser snow geese based on early season climatic variables. Global Change Biol 4:3–16CrossRefGoogle Scholar
  23. Smith TG (1980) Polar bear predation of ringed and bearded seals in the land-fast sea ice habitat. Can J Zool 58:2201–2209CrossRefGoogle Scholar
  24. Stempniewicz L (2006) Polar bear predatory behaviour towards molting barnacle geese and nesting glaucous gulls on Spitsbergen. Arctic 59:247–251Google Scholar
  25. Stirling I, Derocher AE (1993) Possible impacts of climatic warming on polar bears. Arctic 46:240–245Google Scholar
  26. Stirling I, McEwan EH (1975) The calorific value of whole ringed seals (Phoca hispida) in relation to polar bear (Ursus maritimus) ecology and hunting behaviour. Can J Zool 53:1021–1027CrossRefPubMedGoogle Scholar
  27. Stirling I, Parkinson CL (2006) Possible effects of climate warming on selected populations of polar bears (Ursus maritimus) in the Canadian Arctic. Arctic 59:261–275Google Scholar
  28. Stirling I, Jonkel C, Smith P, Robertson R (1977) The ecology of the polar bear (Ursus maritimus) along the western coast of Hudson Bay. Canadian Wildlife Service Occasional Paper 33Google Scholar
  29. Stirling I, Lunn NJ, Iacozza J (1999) Long-term trends in the population ecology of polar bears in western Hudson Bay in relation to climatic change. Arctic 52:294–306Google Scholar
  30. Stirling I, Lunn NJ, Iacozza J, Elliott C, Obbard M (2004) Polar bear distribution and abundance on the southwestern Hudson Bay coast during the open water season, in relation to population trends and annual ice patterns. Arctic 57:15–26Google Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Paul A. Smith
    • 1
  • Kyle H. Elliott
    • 2
  • Anthony J. Gaston
    • 1
  • H. Grant Gilchrist
    • 1
  1. 1.Environment Canada—National Wildlife Research CentreOttawaCanada
  2. 2.Department of ZoologyUniversity of ManitobaWinnipegCanada

Personalised recommendations