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Bourque J, Dietz R, Sonne C, St Leger J, Iverson S, Rosing-Asvid A, Hansen M, McKinney MA
Feeding habits of a new Arctic predator: insight from full-depth blubber fatty acid signatures of Greenland, Faroe Islands, Denmark, and managed-care killer whales Orcinus orca
Killer whales recently observed in the eastern Canadian Arctic, sub-Arctic and Greenland may prey on Arctic and sub-Arctic marine mammals. To evaluate the feeding behaviour of these supposedly fish-feeding North Atlantic stocks within new northern habitats, Bourque and co-workers compared blubber fatty acid signatures from killer whales in Greenland to those from Denmark and the Faroe Islands, as well as to fish-fed, managed-care individuals. Killer whales in Greenlandic waters showed distinct signatures from other North Atlantic individuals and especially from the fish-fed individuals. Fatty acid markers linked to marine mammal feeding in other killer whale populations were significantly higher in the Greenland killer whales, demonstrating the importance of seals and whales to the diet of this new Arctic predator.