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

• Main Authors: Reisinger, RR, de Bruyn, PJN, Tosh, CA, Oosthuizen, WC, Mufanadzo, NT, Bester, MN
• Format: Article in Journal/Newspaper
• Language: English
• Published: NISC 2011
• Subjects: Antarctic; Southern Ocean; Antarc*; Elephant Seals; Killer Whale; Marion Island; Mirounga leonina; Orca; Orcinus orca; Killer whale
• Online Access: http://www.ajol.info/index.php/ajms/article/view/66770

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