Biology and behavior of killer whales

Since it’s inception Cascadia Research biologists working in the field have taken photos of killer whales when encountered and contributed them to a variety of research projects being undertaken along the west coast of North America. Starting in 2003 Cascadia began a variety of research efforts focused on killer whales, most in collaboration with the Northwest Fisheries Science Center of NOAA Fisheries and a continuation of long-term studies of killer whales being undertaken by Robin Baird. Recent projects have focused on studying the underwater acoustics and behavior of Southern Resident killer whales using DTAGs, diving behavior of mammal-eating killer whales, movement patterns of mammal-eating killer whales, and a study of diet and behavioral cues of predation in fish-eating killer whales. This latter project was begun in 2002 in collaboration with Dr. Brad Hanson of the Northwest Fisheries Science Center and has involved collecting fecal samples (for genetic analysis of diet) and prey remains left behind foraging whales. As part of the effort to examine diet and underwater behavior, with Greg Marshall and Dr. Mike Heithaus of the National Geographic Television Remote Imaging Program a Crittercam was deployed on a fish-eating “southern resident” killer whale (K25) in 2002, obtaining the first underwater video footage collected from a killer whale. Unfortunately the whale was not foraging while the camera was attached, but the video footage obtained did demonstrate that this technique should be useful to examine underwater feeding.


Books, book chapters and popular articles

Killer Whales of the World book cover, with breaching killer whale
Killer whales of the world: natural history and conservation. Book by R.W. Baird published jointly by Colin Baxter Photography in Europe and Voyageur Press in North America in 2002, and reprinted as a softcover by Voyageur Press in 2006. This book is no longer in print, but the 2002 UK version is available here as a pdf to download.

The killer whale – foraging specializations and group hunting. A review chapter by R.W. Baird published in the book Cetacean Societies in 2000 by the University of Chicago Press. Download Adobe PDF copy

Predators, prey, and play: killer whales and other marine mammals. An article by R.W. Baird published in Whalewatcher in 2011. Download PDF copy

Peer-reviewed publications

  • Harassment and killing of porpoises (“phocoenacide”) by fish-eating Southern Resident killer whales (Orcinus orca). Paper published by D.A. Giles and others, published in Marine Mammal Science in 2023. Download PDF copy
  • Endangered predators and endangered prey: seasonal diet of Southern Resident killer whales. Paper by M.B. Hanson, and others, published in PLoS One in 2021. Download PDF copy
  • Killer whale predatory scarring on mysticetes: a comparison of rake marks among blue, humpback, and gray whales in the Eastern North Pacific. Paper by E Corsi, J. Calambokidis, K.R. Flynn and G.H Steiger, published in Marine Mammal Science in 2021. View a read-only copy
  • Pathology findings and correlation with body condition index in stranded killer whales (Orcinus orca) in the Northeastern Pacific and Hawaii from 2004 to 2013. Paper by S. Raverty and others, published in PLoS ONE in 2020. Download PDF copy
  • Killer whale genomes reveal a complex history of recurrent admixture and vicariance. Paper by A.D. Foote, M.D. Martin, M. Louis, G. Pacheco, K.M. Robertson, M.S. Sinding, A.R. Amaral, R.W. Baird and others, published in Molecular Ecology in 2019. View a read-only copy.​​
  • Noise levels received by endangered killer whales Orcinus orca before and after implementation of vessel regulations. Paper by M. M. Holt, M. B. Hanson, D. A. Giles, C. K. Emmons, J. T. Hogan, published in Endangered Species Research in 2017. Download PDF copy
  • Estimation of a killer whale (Orcinus orca) population’s diet using sequencing analysis of DNA from feces. Paper by M.J. Ford, J. Hempelmann, M.B. Hanson, K.L. Ayres, R.W. Baird and others, published in PLoS One in 2015. Download PDF copy
  • Changes in the occurrence and behavior of mammal-eating killer whales in southern British Columbia and Washington State, 1987-2010. Paper by J. Houghton, R.W. Baird, C.K. Emmons and M.B. Hanson, published in Northwest Science in 2015. Download PDF copy
  • Distinguishing the impacts of inadequate prey and vessel traffic on an Endangered killer whale (Orcinus orca) population Paper by K.L. Ayres, R.K. Booth, J.A. Hempelmann, K.S. Koski, C.K. Emmons, R.W. Baird and others, published in PLoS One in 2012. Download PDF copy
  • Inferred paternity and male reproductive success in a killer whale (Orcinus orca) population. Paper by M.J. Ford, M.B. Hanson, J.A. Hempelmann, K.L. Ayres, C.K. Emmons, G.S. Schorr, R.W. Baird and others in Journal of Heredity in 2011. Download PDF copy
  • Species and stock identification of prey consumed by endangered southern resident killer whales in their summer range. Paper by M.B. Hanson, R.W. Baird, J.K.B. Ford, J. Hempelmann-Halos, D.M. Van Doornik, J.R. Candy, C.K. Emmons, G.S. Schorr, B. Gisborne and others in Endangered Species Research in 2010. Download PDF copy
  • Effects of age, sex and reproductive status on persistent organic pollutant concentrations in “Southern Resident” killer whales. Paper by M.M. Krahn, M.B. Hanson, G.S. Schorr, C.K. Emmons, D.G. Burrows, J.L. Bolton, R.W. Baird and G.M.Ylitalo, published in Marine Pollution Bulletin in 2009. Download PDF copy
  • Vulnerability of a killer whale social network to disease outbreaks. Paper by P.R. Guimaraes Jr., M.A. de Menezes, R.W. Baird, D. Lusseau, P. Guimaraes, and S.F. dos Reis, published in Physical Review E. in 2007. Download PDF copy
  • Persistent organic pollutants and stable isotopes in biopsy samples (2004/2006) from Southern Resident killer whales. Paper by M.M. Krahn, M.B. Hanson, R.W. Baird, R.H. Boyer, D.G. Burrows, C.K. Emmons, J.K.B. Ford, L.L. Jones, D.P. Noren, P.S. Ross, G.S. Schorr, and T.K. Collier, published in Marine Pollution Bulletin in 2007. Download PDF copy
  • Killer whales in Hawaiian waters: information on population identity and feeding habits. Paper by R.W. Baird, D.J. McSweeney, C. Bane, J. Barlow, D.R. Salden, L.K. Antoine, R.G. LeDuc, and D.L. Webster, published in Pacific Science in 2006.Download PDF copy
  • Suspected surplus killing of harbor seal pups (Phoca vitulina) by killer whales (Orcinus orca). Paper by J.K. Gaydos, S. Raverty, R.W. Baird and R.W. Osborne, published in Northwestern Naturalist in 2005. Download PDF copy
  • Factors influencing the diving behaviour of fish-eating killer whales: sex differences and diel and interannual variation in diving rates. Paper by R.W. Baird, M.B. Hanson and L.M. Dill published in the Canadian Journal of Zoology in 2005. Download PDF copy
  • Low worldwide genetic diversity in the killer whale (Orcinus orca): implications for demographic history. Paper by A.R. Hoelzel, A. Natoli, M.E. Dahlheim, C. Olavarria, R.W. Baird and N.A. Black published in the Proceedings of the Royal Society of London in 2002. Download PDF copy
  • Social organization of mammal-eating killer whales: group stability and dispersal patterns. Paper by R.W. Baird and H. Whitehead published in the Canadian Journal of Zoology in 2000. Download PDF copy
  • Status of killer whales in Canada. Paper by R.W. Baird published in the Canadian Field-Naturalist in 2001. Download PDF copy
  • Birth of a “resident” killer whale off Victoria, British Columbia, Canada. Note by P.J. Stacey and R.W. Baird, published in Marine Mammal Science in 1997. Download Adobe PDF copy
  • Ecological and social determinants of group size in transient killer whales. Paper by R.W. Baird and L.M. Dill published in Behavioral Ecology in 1996. Download Adobe PDF copy
  • Levels of organochlorine compounds, including PCDDs and PCDFs, in the blubber of cetaceans from the west coast of North America. Paper by W.M. Jarman and colleagues published in Marine Pollution Bulletin in 1996. Download Adobe PDF copy
  • Occurrence and behaviour of transient killer whales: seasonal and pod-specific variability, foraging behaviour and prey handling. Paper by R.W. Baird and L.M. Dill published in Canadian Journal of Zoology in 1995. Download Adobe PDF copy
  • Possible indirect interactions between transient and resident killer whales: implications for the evolution of foraging specializations in the genus Orcinus. Paper by R.W. Baird, P.A. Abrams and L.M. Dill published in Oecologia in 1992. Download Adobe PDF copy
  • A review of killer whale interactions with other marine mammals: predation to co-existence. Paper by T.A. Jefferson, P.J. Stacey and R.W. Baird published in Mammal Review in 1991. Download Adobe PDF copy
  • Observations on the reactions of sea lions, Zalophus californianus and Eumetopias jubatus, to killer whales, Orcinus orca, evidence of “prey” having a “search image” for predators. Paper by R.W. Baird and P.J. Stacey published in Canadian Field-Naturalist in 1989. Download Adobe PDF copy
  • Variation in saddle patch pigmentation in populations of killer whales (Orcinus orca) from British Columbia, Alaska, and Washington State. Paper by R.W. Baird and P.J. Stacey published in Canadian Journal of Zoology in 1988. Download Adobe PDF copy

Reports, conference presentations, and a few other things

  • Diet studies of “southern resident” killer whales: prey sampling and behavioral cues of predation. Report by R.W. Baird and M.B. Hanson to NOAA, 2004. Download Adobe PDF copy
  • Studies of foraging in “southern resident” killer whales during July 2002: dive depths, bursts in speed, and the use of a “Crittercam” system for examining sub-surface behavior. Report submitted in February 2003 to the National Marine Mammal Laboratory, Seattle, WA, by R.W. Baird, M.B. Hanson, E.E. Ashe, M.R. Heithaus and G.J. Marshall. Download PDF copy
  • Diving behaviour of killer whales. Abstract of a presentation by R.W. Baird, L.M. Dill and M.B. Hanson, to the World Marine Mammal Conference, held in Monaco in 1998.
  • Information on killer whale reactions to suction-cup tagging can also be found in an Abstract to a presentation at a workshop on “Methods for Assessing Behaviorial Impacts On Marine Mammals from Human Activities”, held in Monaco in 1998.
  • Management of killer whale/boat interactions in Haro Strait. Abstract of a presentation authored by R.W. Baird, R. Otis and R.W. Osborne, from a workshop on “Whale Watching Research” held in Monaco in 1998.
  • Diving behavior of fish-eating killer whales off southern Iceland. Poster Presentation by J.L. Schorr, R.W. Baird, J.J. Foster, and M.B. Hanson at the 14th Biennial Conference of the Society of Marine Mammalogy, Vancouver, British Columbia, Canada 28 Nov – 3 Dec, 2001. Download PDF copy
  • Preliminary calibration of velocity meters on a captive killer whale. Report prepared by R.W. Baird for the Free Willy Keiko Foundation, Newport, Oregon, in 1998. Download PDF copy
  • Orca Survey field guide to transients of the Haro Strait area. Text from a catalogue authored by A.M. van Ginneken, D.K. Ellifrit and R.W. Baird, published by the Center for Whale Research, Friday Harbor, WA in 1998.
  • Foraging behaviour and ecology of transient killer whales. Ph.D. Thesis of R.W. Baird, completed in 1994. Most of the thesis has been published in the above-noted papers in Behavioral Ecology, Oecologia and Canadian Journal of Zoology, but the epilogue (which focuses on the question of whether “transient” killer whales are a different species from the fish-eating “residents”) and some of the appendices are not published.
  • Transient killer whale (Orcinus orca) harassment, predation, and “surplus killing” of marine birds in British Columbia Abstract of a conference presentation by P.J. Stacey, R.W. Baird and A.B. Hubbard-Morton, published in the Pacific Seabird Group Bulletin in 1990. Download Adobe PDF copy
  • Foraging and feeding behavior of transient killer whales. Article by R.W. Baird and P.J. Stacey published in Whalewatcher, the Journal of the American Cetacean Society, in 1988. Download Adobe PDF