Killer Whale

The killer whale (Orcinus orca) is the top marine predator and perhaps the most widespread vertebrate on earth, occurring in all the world’s oceans. They prey on protected marine mammal populations and commercially important fish stocks, and we need to understand the impacts of this predation, particularly in rapidly changing ecosystems. We are therefore undertaking a multi-faceted, but integrated, research program to study killer whales in a number of different locations (Pitman 2011).

TaxonomyCurrently recognized as a single species, our recent genetic investigations have suggested that there may be multiple species of killer whales (Morin et al. 2010). Notably, our research has revealed that there are at least 4 distinct forms of killer whales in Antarctic and Southern Ocean waters (Pitman and Ensor 2003; Pitman et al. 2010), with distinct genetic differences (LeDuc et al. 2008; Foote et al. 2011) and morphological differences (Pitman et al. 2007a; see poster).

MovementsThe impact of killer whale predation on local prey populations will be mediated by their movements. We deploy small (49g) satellite tags on killer whales to provide higher resolution and longer term monitoring of their movement patterns. This approach is being used to study the migration patterns of Antarctic killer whales (Andrews et al., 2008; Durban and Pitman, 2011), the movement patterns of killer whales hunting migratory gray whales off the west coast of the United States, and to locate whales in real time to observe predation behavior (Pitman and Durban, 2011).