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Behavioral Ecology and Sociobiology

, Volume 63, Issue 12, pp 1773–1785 | Cite as

Underwater and above-water search patterns of an Arctic seabird: reduced searching at small spatiotemporal scales

  • Kyle Hamish ElliottEmail author
  • Roger D. Bull
  • Anthony J. Gaston
  • Gail K. Davoren
Original Paper

Abstract

How predators vary search patterns in response to prey predictability is poorly known. For example, marine invertebrates may be predictable but of low energy value, while fish may be of higher energy value but unpredictable at large (pelagic schools) or small (solitary benthics) spatial scales. We investigated the search patterns of the thick-billed murre (Uria lomvia), an Arctic seabird feeding on invertebrates, pelagic fish, or benthic fish. Foraging ranges at the Coats Island colony are generally smaller (<240 min per trip) than at larger colonies, and many birds specialize in foraging tactics and diet. Underwater search times for benthic fish were higher than for pelagic fish or invertebrates while above-water search times for pelagic fish were higher than for benthic fish or invertebrates. There were few stops during trips. Total trip time, flying time, number of flights, and number of dives were intercorrelated and increased with prey energy content, suggesting that longer trips involved fewer prey encounters due to selection of higher-quality, but rarer, prey items. Flight times were not Lévy-distributed and seabirds may have used area-restricted searches. The high degree of specialization, apparent absence of information center effects, and reduced above-water searching times may be linked to the relatively small colony size and the resulting short commuting distances to feeding areas, leading to greater prey predictability. We concluded that prey predictability over various scales affected predator search patterns.

Keywords

Predator–prey interactions Ecological scale Lévy search pattern Information Center Hypothesis Thick-billed murre Uria lomvia 

Notes

Acknowledgements

We thank B. Addison, K. Ashbrook, M. Barrueto, A. Hargreaves, M. Hipfner, S. Jacobs, G. Lancton, A. Moody, J. Provencher, A. Ronson, K. Skebo, P. Smith, K. Woo, and P. Woodward for help in the field. A. Fromevitch, K. Hedges, and P. Turko helped with data compilation. J. Nakoolak kept us safe from bears. A. Burger, D. Gillis, and an anonymous reviewer provided excellent comments on an earlier version of the manuscript. KHE benefited from funding provided by NSERC Postgraduate (M) Award, NSERC Northern Research Internship, Andrew Taylor Northern Research Grant, Mountain Equipment Co-op Studentship, Arctic Institute of North America Grant-in-aid, Malcolm Ramsay Award, Frank M. Chapman Memorial Fund, Society of Canadian Ornithologists/Bird Studies Canada Taverner Award, and the Northern Scientific Training Program through the Department of Indian Affairs and Northern Development. The Canadian Wildlife Service Migratory Birds Division, 2007–2008 International Polar Year, the Polar Continental Shelf Project, and the University of Manitoba also funded this project. R. Armstrong at the Nunavut Research Institute, M. Mallory at the Canadian Wildlife Service Northern Research Division, and C. Eberl at the Canadian Wildlife Service in Ottawa provided logistical support. All procedures were approved under the guidelines of the Canadian Committee for Animal Care (Protocol Number F04-030).

Supplementary material

265_2009_801_MOESM1_ESM.mht (530 kb)
ESM Table S1 (MHT 529 kb)
265_2009_801_MOESM2_ESM.doc (24 kb)
ESM Time at splashdown (±SE) increases with time at the colony prior to departure.
265_2009_801_MOESM3_ESM.doc (49 kb)
ESM Frequency distribution for (a) arrival and (b) departure times using actual data (columns) and simulations (lines) for thick-billed murres at Coats Island 1999-2007. (DOC 49.0 kb)

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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Kyle Hamish Elliott
    • 1
    Email author
  • Roger D. Bull
    • 2
    • 3
  • Anthony J. Gaston
    • 2
  • Gail K. Davoren
    • 1
  1. 1.Department of ZoologyUniversity of ManitobaWinnipegCanada
  2. 2.Science and Technology BranchEnvironment CanadaOttawaCanada
  3. 3.Canadian Museum of NatureOttawaCanada

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