Marine Biology

, Volume 160, Issue 3, pp 531–539 | Cite as

Size and seasonal influences on the foraging range of female grey seals in the northeast Atlantic

  • M. CroninEmail author
  • P. Pomeroy
  • M. Jessopp
Original Paper


Evidence of segregation in foraging habitat has been demonstrated in some top marine predators, including cetaceans, pinnipeds and seabirds. However, most data are not adequate to assess differences relating to body size or seasonal influences. This has implications for quantitative modelling of population-level predator–prey interactions and ecosystem structure. We examined potential influence of body size and ‘fatness’ on the foraging trip characteristics of a top marine predator, the Atlantic grey seal (Halichoerus grypus), in southwest Ireland within the framework of optimal foraging theory to examine how female grey seals foraging behaviour varied with size, and across the period between moult and breeding. Larger seals undertook trips of greater duration and travelled further from haul-out sites than smaller seals. However, body fat was negatively associated with trip duration and extent. Seals spent more time at sea during the summer, but trips were shorter in extent, suggesting more localized foraging during this season.


Body Size Harbour Seal Elephant Seal Trip Duration Grey Seal 
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 was facilitated by funding from the Higher Education Authority (HEA) under the PRTLI4 programme Environment and Climate Change and by the National Parks & Wildlife Service (NPWS). Research was also supported under the Beaufort Marine Research Award carried out under the Sea Change Strategy and the Strategy for Science Technology and Innovation (2006-2013), with the support of the Marine Institute, funded under the Marine Research Sub-Programme of the National Development Plan 2007–2013. All seal handling and tagging procedures were conducted under NPWS License No C35/2008. We would like to thank William Patterson (SMRU), David Thompson (National Trust), Declan O’Donnell, Clare Heardman, Frank McMahon, Pascal Dower, Tim O’Donoghue, Oliver Ó Cadhla and Danny O’Keefe (NPWS) for valuable field assistance during seal tagging and Alain Zuur for statistical advice. We would also like to thank two anonymous reviewers for constructive comments that greatly improved the manuscript.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Coastal & Marine Research CentreUniversity College CorkCorkIreland
  2. 2.Sea Mammal Research Unit, Scottish Oceans InstituteUniversity of St AndrewsSt Andrews, FifeUK

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