Get access

Evidence for fatal collisions and kleptoparasitism while plunge-diving in Gannets

Authors

  • GABRIEL E. MACHOVSKY CAPUSKA,

    Corresponding author
    1. Nutritional Ecology Research Group, and
    2. Coastal-Marine Research Group, Institute of Natural Sciences, Massey University, Private Bag 102 904 North Shore MSC, Auckland, New Zealand
    Search for more papers by this author
  • SARAH L. DWYER,

    1. Coastal-Marine Research Group, Institute of Natural Sciences, Massey University, Private Bag 102 904 North Shore MSC, Auckland, New Zealand
    Search for more papers by this author
  • MAURICE R. ALLEY,

    1. New Zealand Wildlife Health Center, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11-222, Palmerston North, New Zealand
    Search for more papers by this author
  • KAREN A. STOCKIN,

    1. Coastal-Marine Research Group, Institute of Natural Sciences, Massey University, Private Bag 102 904 North Shore MSC, Auckland, New Zealand
    Search for more papers by this author
  • DAVID RAUBENHEIMER

    1. Nutritional Ecology Research Group, and
    2. Coastal-Marine Research Group, Institute of Natural Sciences, Massey University, Private Bag 102 904 North Shore MSC, Auckland, New Zealand
    Search for more papers by this author

Corresponding author.
Email: g.machovsky@massey.ac.nz

Abstract

Plunge-diving is a highly successful strategy for dealing with the challenges confronting birds feeding on pelagic prey. We tested for evidence of fatal injuries due to collision between conspecifics in plunge-diving Australasian Gannets Morus serrator and Cape Gannets Morus capensis, respectively, by performing post-mortem examinations of carcasses recovered from New Zealand waters and analysing video footage of Cape Gannet foraging events from South Africa. We found evidence of accidental collisions between Gannets and also observed a case of attempted kleptoparasitism, in which a diving Cape Gannet targeted a previously captured fish in the beak of a conspecific.

Ancillary