, Volume 108, Issue 1, pp 192–196

Cross-shoal variability in the feeding habits of migrating Atlantic cod (Gadus morhua)

  • Elisabeth M. DeBlois
  • George A. Rose
Behavioural Ecology


Prey intake and selection were related to within-shoal position for Atlantic cod (Gadus morhua) engaged in annual migration across the Newfoundland shelf in the northwest Atlantic. Comparisons made among fish occupying five regions from the front to rear of a large (>10 km across) migrating shoal indicated that leading fish, or scouts, were larger, ate more food by weight, and had a more varied diet than did fish at other positions. Also, scouts consumed more preferred prey types (fish and pelagic invertebrates) than did fish at other positions. In contrast, trailing fish consumed few fish prey but a larger proportion of benthic invertebrates. Our results are the first to document systematic heterogeneous feeding success among members of a free-ranging and migrating fish shoal in the open ocean.

Key words

Gadus morhua Fish shoals Shoal position Feeding 


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Copyright information

© Springer-Verlag 1996

Authors and Affiliations

  • Elisabeth M. DeBlois
    • 1
  • George A. Rose
    • 1
  1. 1.Department of Fisheries and OceansSt John'sCanada
  2. 2.Fisheries Conservation ChairFisheries and Marine Institute, Memorial University of NewfoundlandSt. John'sCanada

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