Observations of Humpback Whale, Megaptera novaeangliae Killer Whale, Orcinus orca, interactions in Alaska: comparison with terrestrial predator-prey relationships

Mammalian predator-prey interactions range from total disregard to active attack.Levels of interactions which occur during encounters between potential predators and their prey have been arranged into five classes.A comparison between the predator-prey relationships of Humpback~-Killer whales and those of large African mammals is presented.Killer Whales are not always highly aggressive predators of other cetaceans, but instead, like lions in the terrestrial system, coexist in a usually non-belligerent, if uneasy, manner with those species able to defend themselves against attacks.Eighteen instances were recorded in which Killer Whales were within | km of Humpback Whales, and no aggressive interactions were witnessed.A situation is described having no terrestrial analogue, in which Humpback Whales, including small individuals and a female with a calf, joined with a pod of Killer Whales actively attacking a sea lion.