Marine Biology

, Volume 150, Issue 6, pp 1441–1452 | Cite as

Age-related shifts in the diet composition of southern elephant seals expand overall foraging niche

  • Iain C. FieldEmail author
  • Corey J. A. Bradshaw
  • John van den Hoff
  • Harry R. Burton
  • Mark A. Hindell
Research Article


Southern elephant seals are important apex predators in a highly variable and unpredictable marine environment. In the presence of resource limitation, foraging behaviours evolve to reduce intra-specific competition increasing a species’ overall probability of successful foraging. We examined the diet of 141 (aged 1–3 years) juvenile southern elephant seals to test the hypotheses that differences between ages, sexes and seasons in diet structure occur. We described prey species composition for common squid and fish species and the mean size of cephalopod prey items for these age groups. Three cephalopod species dominated the stomach samples, Alluroteuthis antarcticus, Histioteuthis eltaninae and Slosarczykovia circumantarcticus. We found age-related differences in both species composition and size of larger prey species that probably relate to ontogenetic changes in diving ability and haul-out behaviour and prey availability. These changes in foraging behaviour and diet are hypothesised to reduce intra-specific food competition concomitant with the increase in foraging niche of growing juveniles.


Southern Ocean Prey Species Diet Composition Elephant Seal Southern Elephant 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.



The data were collected with the approval of the Australian Antarctic Animal Ethics Committee and permits from the Tasmanian Parks and Wildlife Service . We thank M. Biuw, J. Harrington, C. McKinley, N. Milius, R. Munro, M. Pauza and K. Wheatley and members of the 51st–53rd ANARE to Macquarie Island for their assistance during fieldwork. We thank D. Williams for the identification of the otoliths collection and Y. Cherel and M. Imber for reviewing our identifications of squid beaks. We thank M. Sumner for helping with R programming. Funding was provided by the Antarctic Science Advisory Committee and Sea World Research and Rescue Foundation Inc.


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Iain C. Field
    • 1
    • 2
    • 3
    Email author
  • Corey J. A. Bradshaw
    • 1
    • 3
  • John van den Hoff
    • 2
  • Harry R. Burton
    • 2
  • Mark A. Hindell
    • 1
  1. 1.Antarctic Wildlife Research Unit, School of ZoologyUniversity of TasmaniaHobartAustralia
  2. 2.Australian Antarctic DivisionChannel HighwayKingstonAustralia
  3. 3.School for Environmental ResearchCharles Darwin UniversityDarwinAustralia

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