Prey and seasonal abundance of killer whales at sub-Antarctic Marion Island

  • RR Reisinger
  • PJN de Bruyn
  • CA Tosh
  • WC Oosthuizen
  • NT Mufanadzo
  • MN Bester

Abstract

The diet of killer whales Orcinus orca was investigated from 48 predation events observed during sightings at sub-Antarctic Marion Island between 2006 and 2009. From these events, there were 10 cases where prey could be identified. Killer whales fed on fur seals Arctocephalus tropicalis, elephant seals Mirounga leonina and penguins. Constant effort (dedicated) observations (259 hours, 2008–2009) showed that the peak in killer whale abundance was between September and December with a secondary peak between April and May, which coincided with peaks in the abundance of seals and penguins.

Keywords: Orcinus orca, seals, diet, foraging, Southern Ocean, seasonal occurrence

African Journal of Marine Science 2011, 33(1): 99–105

Author Biographies

RR Reisinger
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
PJN de Bruyn
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
CA Tosh
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
WC Oosthuizen
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
NT Mufanadzo
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
MN Bester
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
Section
Articles

Journal Identifiers


eISSN: 1814-2338
print ISSN: 1814-232X