Fine-scale foraging movements by fish-eating killer whales (Orcinus orca) relate to the vertical distributions and escape responses of salmonid prey (Oncorhynchus spp.)
Wright, Brianna M.
Ford, John K. B.
Ellis, Graeme M.
Shapiro, Ari D.
Battaile, Brian C.
Trites, Andrew W.
MetadataShow full item record
KeywordForaging; Movement; Diving behavior; Biologging; Dtag; Accelerometry; Killer whale; Orcinus orca; Pacific salmon
We sought to quantitatively describe the fine-scale foraging behavior of northern resident killer whales (Orcinus orca), a population of fish-eating killer whales that feeds almost exclusively on Pacific salmon (Oncorhynchus spp.). To reconstruct the underwater movements of these specialist predators, we deployed 34 biologging Dtags on 32 individuals and collected high-resolution, three-dimensional accelerometry and acoustic data. We used the resulting dive paths to compare killer whale foraging behavior to the distributions of different salmonid prey species. Understanding the foraging movements of these threatened predators is important from a conservation standpoint, since prey availability has been identified as a limiting factor in their population dynamics and recovery. Three-dimensional dive tracks indicated that foraging (N = 701) and non-foraging dives (N = 10,618) were kinematically distinct (Wilks’ lambda: λ 16 = 0.321, P < 0.001). While foraging, killer whales dove deeper, remained submerged longer, swam faster, increased their dive path tortuosity, and rolled their bodies to a greater extent than during other activities. Maximum foraging dive depths reflected the deeper vertical distribution of Chinook (compared to other salmonids) and the tendency of Pacific salmon to evade predators by diving steeply. Kinematic characteristics of prey pursuit by resident killer whales also revealed several other escape strategies employed by salmon attempting to avoid predation, including increased swimming speeds and evasive maneuvering. High-resolution dive tracks reconstructed using data collected by multi-sensor accelerometer tags found that movements by resident killer whales relate significantly to the vertical distributions and escape responses of their primary prey, Pacific salmon.
© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Movement Ecology 5 (2017): 3, doi:10.1186/s40462-017-0094-0.
Suggested CitationMovement Ecology 5 (2017): 3
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
Orchestration : the movement and vocal behavior of free-ranging Norwegian killer whales (Orcinus orca) Shapiro, Ari D. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2008-06)Studying the social and cultural transmission of behavior among animals helps to identify patterns of interaction and information content flowing between individuals. Killer whales are likely to acquire traits culturally ...
Mehta, Amee V.; Allen, Judith M.; Constantine, Rochelle; Garrigue, Claire; Jann, Beatrice; Jenner, Curt; Marx, Marilyn K.; Matkin, Craig O.; Mattila, David K.; Minton, Gianna; Mizroch, Sally A.; Olavarría, Carlos; Robbins, Jooke; Russell, Kirsty G.; Seton, Rosemary E.; Steiger, Gretchen H.; Víkingsson, Gísli A.; Wade, Paul R.; Witteveen, Briana H.; Clapham, Phillip J. (Inter-Research, 2007-10-25)Certain populations of killer whales Orcinus orca feed primarily or exclusively on marine mammals. However, whether or not baleen whales represent an important prey source for killer whales is debatable. A hypothesis by ...
Distinctions in sound patterns of calls by killer whales (Orcinus Orca) from analysis of computer sound features Watkins, William A.; Daher, Mary Ann; DiMarzio, Nancy A.; Reppucci, Gina (Woods Hole Oceanographic Institution, 1998-03)Calls of killer whales, Orcinus orca, were analyzed using computed sound features to classify sound patterns and identify call similarties. Calls were classified and separated according to the podfamily group within clans ...