Killer whale ( Orcinus orca

We identified individual killer whales (Orcinus orca) using recent (2004–09) photographs to obtain a minimum count of whales that use eastern Canadian Arctic waters. Fifty-three individuals were identified from nine different sightings; 11 individuals from western Hudson Bay sightings and 42 from the areas around northern and eastern Baffin Island. One whale was re-sighted: an adult female or large juvenile photographed 17 days and 375 km apart at Churchill, Manitoba, and off-shore of Rankin Inlet, Nunavut, in August 2007. With only one individual re-sighted, the number of individuals that use this area is likely much larger. No re-sightings occurred between Arctic killer whales and individuals photographed off the coast of Newfoundland. Our results represent the minimum number of killer whales sighted in eastern Canadian Arctic waters and provide the foundation for further killer whale research. Little is known about Arctic killer whales and, as a top predator, it is unclear what effect they have on Arctic marine ecosystems