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Population size, survival and reproductive rates of northern Norwegian killer whales (Orcinus orca) in 1986–2003

Published online by Cambridge University Press:  07 August 2013

Sanna Kuningas ,
Tiu Similä  and
Philip S. Hammond
Sanna Kuningas*
Affiliation:
Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife, KY16 8LB, UK
Tiu Similä
Affiliation:
Wild Idea, Box 181, 8465 Straumsjøen, Norway
Philip S. Hammond
Affiliation:
Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife, KY16 8LB, UK
*
Correspondence should be addressed to: S. Kuningas, Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife, KY16 8LB, UK email: sk297@st-andrews.ac.uk
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Abstract

A long-term photo-identification study of killer whales (Orcinus orca) in northern Norway was initiated in 1986, when their prey the Norwegian spring-spawning herring (Clupea harengus) started to winter in a complex fjord system. The aim of this work was to estimate population size and apparent survival rates in this killer whale population using photo-identification and mark–recapture techniques with data collected during October–December 1986–2003. Total population size was estimated to be highest in 2003: 731 individuals (SE = 139, 95% CI = 505–1059) using a model taking heterogeneity of capture probabilities into account. Apparent survival of adult males and adult females was estimated using the Cormack–Jolly–Seber model as 0.971 (SE = 0.008) and 0.977 (SE = 0.009), respectively. Calving intervals ranged from 3 to 14 years (mean = 5.06, SE = 0.722). These are the first estimates of northern Norwegian killer whale population parameters, allowing their dynamics to be investigated and comparisons to be made with killer whale populations globally.

Keywords

photo-identificationmark–recapturelong-term studypopulation sizesurvivalfecundityOrcinus orcaNorway
Type
Research Article
Information
Journal of the Marine Biological Association of the United Kingdom , Volume 94 , Issue 6 , September 2014 , pp. 1277 - 1291
Copyright
Copyright © Marine Biological Association of the United Kingdom 2013 

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References

REFERENCES

Anderson, D.R., Burnham, K.P. and White, G.C. (1994) AIC model selection in overdispersed capture–recapture data. Ecology 75, 1780–1793.CrossRefGoogle Scholar
Bigg, M. (1982) An assessment of killer whale (Orcinus orca) stocks off Vancouver Island, British Columbia. Report of the International Whaling Commission 32, 655–666.Google Scholar
Bigg, M.A., Olesiuk, P.F. and Ellis, G.M. (1990) Social organization and genealogy of resident killer whales (Orcinus orca) in the coastal waters of British Columbia and Washington State. Report of the International Whaling Commission, Special Issue 12, 383–399.Google Scholar
Bisther, A. and Vongraven, D. (1995) Studies of the social ecology of Norwegian killer whales (Orcinus orca). In Blix, A.S., Walloe, L. and Ulltang, O. (eds) Whales, seals, fish and man. Amsterdam: Elsevier, pp. 169–176.Google Scholar
Boyd, I., Wanless, S. and Camphuysen, C.J. (2006) Top predators in marine ecosystems. Their role in monitoring and management. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Burnham, K.P. and Anderson, D.R. (2002) Model selection and multimodel inference. A practical information–theoretic approach 2nd edition. New York: Springer.Google Scholar
Caughley, G. (1966) Mortality patterns in mammals. Ecology 47, 906–918.CrossRefGoogle Scholar
Chao, A. and Huggins, R.M. (2005) Modern closed-population capture–recapture models. In Amstrup, S.C., McDonald, T.L. and Manly, B.F.J. (eds) Handbook of capture–recapture analysis. Princeton, NJ: Princeton University Press, pp. 58–87.Google Scholar
Chao, A., Lee, S.-M. and Jeng, S.-L. (1992) Estimating population size for capture–recapture data when capture probabilities vary by time and individual animal. Biometrics 48, 201–216.CrossRefGoogle ScholarPubMed
Chapman, D.G. (1951) Some properties of the hypergeometric distribution with applications to zoölogical sample censuses. University of California Publication in Statistics. 1, 131–160.Google Scholar
Choquet, R., Lebreton, J.-D., Gimenez, O., Reboulet, A.-M. and Pradel, R. (2009) U-CARE: utilities for performing goodness of fit tests and manipulating CApture–REcapture data. Ecography 32, 1071–1074.CrossRefGoogle Scholar
Choquet, R., Reboulet, A.M., Lebreton, J.D., Gimenez, O. and Pradel, R. (2005) U-CARE 2.2 user's manual. CEFE, Montpellier: CEFE. Available at: http://www.cefe.cnrs.fr/en/biostatistics-and-biology-of-pupulations/software.Google Scholar
Christensen, I. (1982) Killer whales in Norwegian coastal waters. Report for the International Whaling Commission 32, 633–642.Google Scholar
Christensen, I. (1988) Distribution, movements and abundance of killer whales (Orcinus orca) in Norwegian coastal waters, 1982–1987, based on questionnaire surveys. In Sigurjónsson, J. and Leatherwood, S. (eds) North Atlantic killer whales. Rit Fiskideildar 11, 79–88.Google Scholar
Cooch, E. and White, G. (2012) Program MARK, a gentle introduction: 11th edition. Available at: http://www.phidot.org/software/mark/docs/book/ (accessed 30 June 2013).Google Scholar
Cormack, R.M. (1964) Estimates of survival from the sighting of marked animals. Biometrika 51, 429–438.CrossRefGoogle Scholar
Cullon, D.L., Yunker, M.B., Alleyne, C., Dangerfield, N.J., O'Neill, S., Whiticar, M.J. and Ross, P.S. (2009) Persistent organic pollutants in Chinook salmon (Oncorhynchus tshawytscha): implications for resident killer whales of British Columbia and adjacent waters. Environmental Toxicology and Chemistry 28, 148–161.CrossRefGoogle ScholarPubMed
Det Norske, Veritas (2011) Norway spring-spawning herring fishery second surveillance report. Bergen/Tromso: Norges Sildesalgslag/Norwegian Seafood Export Council, Report Number 2011-010.Google Scholar
Dragesund, O., Johannessen, A. and Ulltang, Ø. (1997) Variation in migration and abundance of Norwegian spring spawning herring (Clupea harengus L.). Sarsia 82, 97–105.CrossRefGoogle Scholar
Erbe, C. (2002) Underwater noise of whale-watching boats and potential effects on killer whales (Orcinus orca), based on an acoustic impact model. Marine Mammal Science 18, 394–418.CrossRefGoogle Scholar
Foote, A.D., Newton, J., Piertney, S.B., Willerslev, E. and Gilbert, M.T.P. (2009) Ecological, morphological and genetic divergence of sympatric North Atlantic killer whale populations. Molecular Ecology 18, 5207–5217.CrossRefGoogle ScholarPubMed
Foote, A.D., Vilstrup, J.T., de Stephanis, R., Verborgh, P., Abel Nielsen, S.C., Deaville, R., Kleivane, L., Martín, V., Miller, P.J.O., Øien, N., Pérez-Gil, M., Rasmussen, M., Reid, R.J., Robertson, K.M., Rogan, E., Similä, T., Tejedor, M.L., Vester, H., Víkingsson, G., Willerslev, E., Gilbert, M.T.P. and Piertney, S.B. (2011) Genetic differentiation among North Atlantic killer whale populations. Molecular Ecology 20, 629–641.CrossRefGoogle ScholarPubMed
Ford, J.K.B., Ellis, G.M. and Balcomb, K.C. (2000) Killer whales. The natural history and genealogy of Orcinus orca in British Columbia and Washington. 2nd edition. Vancouver: UBC Press.Google Scholar
Ford, J.K.B., Ellis, G.M., Barrett-Lennard, L.G., Morton, A.B., Palm, R.S. and Balcomb, K.C. III (1998) Dietary specialization in two sympatric populations of killer whales (Orcinus orca) in coastal British Columbia and adjacent waters. Canadian Journal of Zoology 76, 1456–1471.CrossRefGoogle Scholar
Ford, J.K.B., Ellis, G.M., Matkin, D.R., Balcomb, K.C., Briggs, D. and Morton, A.B. (2005) Killer whale attacks on minke whales: prey capture and antipredator tactics. Marine Mammal Science 21, 603–618.CrossRefGoogle Scholar
Ford, J.K.B., Ellis, G.M., Olesiuk, P.F. and Balcomb, K.C. (2010) Linking killer whale survival and prey abundance: food limitation in the oceans' apex predator? Biology Letters 6, 139–142.CrossRefGoogle ScholarPubMed
Forney, K.A. and Wade, P. (2007) Worldwide distribution and abundance of killer whales. In Estes, J. (ed.) Whales, whaling and ecosystems. Berkeley: University of California Press, pp. 145–162.CrossRefGoogle Scholar
Fujiwara, M. and Caswell, H. (2002) A general approach to temporary emigration in mark–recapture analysis. Ecology 83, 3266–3275.Google Scholar
Guinet, C. (1991) Intentional stranding apprenticeship and social play in killer whales (Orcinus orca). Canadian Journal of Zoology 69, 2712–2716.CrossRefGoogle Scholar
Guinet, C., Jouventin, P. and Weimerskirch, H. (1999) Recent population change of the southern elephant seal at Îles Crozet and Îles Kerguelen: the end of the decrease? Antarctic Science 11, 193–197.CrossRefGoogle Scholar
Hammond, P.S. (1986) Estimating the size of naturally marked whale populations using capture–recapture techniques. Report for the International Whaling Commission, Special Issue 8, 253–282.Google Scholar
Hammond, P.S. (1995) Estimating the abundance of marine mammals: a North Atlantic perspective. In Blix, A.S., Walloe, L. and Ulltang, O. (eds) Whales, seals, fish and man. Amsterdam: Elsevier, pp. 3–12.Google Scholar
Hammond, P.S. (2009) Mark–recapture. In Perrin, W.F., Würsig, B. and Thewissen, J.G.M. (eds) Encyclopedia of marine mammals. New York: Academic Press, pp. 705–709.CrossRefGoogle Scholar
Hammond, P.S. (2010) Estimating the abundance of marine mammals. In Boyd, I.L., Bowen, W.D. and Iverson, S.J. (eds) Marine mammal ecology and conservation: a handbook of techniques. Oxford: Oxford University Press, pp. 42–67.Google Scholar
Hickie, B.E., Ross, P.S., Macdonald, R.W. and Ford, J.K.B. (2007) Killer whales (Orcinus orca) face protracted health risks associated with lifetime exposure to PCBs. Environmental Science and Technology 41, 6613–6619.CrossRefGoogle ScholarPubMed
Higdon, J.W., Hauser, D.D. and Ferguson, S.H. (2011) Killer whales (Orcinus orca) in the Canadian Arctic: distribution, prey items, groups sizes, and seasonality. Marine Mammal Science 28, E93–E109.Google Scholar
Holst, J.C., Dragesund, O., Hamre, J., Misund, O.A. and Østvedt, O.J. (2002) Fifty years of herring migrations in the Norwegian Sea. International Council of the Exploration of the Sea Marine Science Symposia 215, 352–360.Google Scholar
Holst, J.C., Røttingen, I. and Melle, W. (2004) The herring. In Skjoldal, H.R. (ed.) The Norwegian Sea ecosystem. Trondheim: Tapir Academic Press, pp. 203–226.Google Scholar
Huse, G., Fernö, A. and Holst, J.C. (2010) Establishment of new wintering areas in herring co-occurs with peaks in the ‘first time/repeat spawner’ ratio. Marine Ecology Progress Series 409, 189–198.CrossRefGoogle Scholar
Huse, G., Railsback, S. and Fernö, A. (2002) Modelling changes in migration pattern of herring: collective behaviour ad numerical domination. Journal of Fish Biology 60, 571–582.CrossRefGoogle Scholar
Jolly, G.M. (1965) Explicit estimates from capture-recapture data with both death and immigration-stochastic model. Biometrika 52, 225–247.CrossRefGoogle ScholarPubMed
Jonsgård, Å. and Lyshoel, P.B. (1970) A contribution to the knowledge of the biology of the killer whale Orcinus orca (L.). Nytt Magasin for Zoologi 18, 41–48.Google Scholar
Krahn, M.M., Hanson, M.B., Schorr, G.S., Emmons, C.K., Burrows, D.G., Bolton, J.L., Baird, R.W. and Ylitalo, G.M. (2009) Effects of age, sex and reproductive status on persistent organic pollutant concentrations in ‘Southern Resident’ killer whales. Marine Pollution Bulletin 58, 1522–1529.CrossRefGoogle ScholarPubMed
Langtimm, C.A., O'Shea, T.J.O., Pradel, R. and Beck, C.A. (1998) Estimates of annual survival probabilities for adult Florida manatees (Trichechus manatus latirostris). Ecology 79, 981–997.CrossRefGoogle Scholar
Lebreton, J.-D., Burnham, K.P., Clobert, L. and Anderson, D.R. (1992) Modeling survival and testing biological hypotheses using marked animals: a unified approach with case studies. Ecological Monographs 62, 67–118.CrossRefGoogle Scholar
LeDuc, R.G., Robertson, K.M. and Pitman, R.L. (2008) Mitochondrial sequence divergence among Antarctic killer whale ecotypes in consistent with multiple species. Biology Letters 4, 426–429.CrossRefGoogle ScholarPubMed
Lusseau, D., Bain, D.E., Williams, R. and Smith, J.C. (2009) Vessel traffic disrupts the foraging behavior of southern resident killer whales Orcinus orca. Endangered Species Research 6, 211–221.CrossRefGoogle Scholar
Lyrholm, T. (1988) Photoidentification of individual killer whales, Orcinus orca, off the coast of Norway, 1983–1986. In Sigurjónsson, J. and Leatherwood, S. (eds) North Atlantic killer whales. Rit Fiskideildar 11, 89–94.Google Scholar
Mann, J. and Smuts, B. (1999) Behavioral development in wild bottlenose dolphin newborns (Tursiops sp.). Behaviour 136, 529–566.Google Scholar
Markowitz, T.M., Harlin, A.D. and Würsig, B. (2003) Digital photography improves efficiency of individual dolphin identification. Marine Mammal Science 19, 217–223.CrossRefGoogle Scholar
Matkin, C.O. and Leatherwood, S. (1986) General biology of the killer whale, Orcinus orca: a synopsis of knowledge. In Kirkevold, B.C. and Lockard, J.S. (eds) Behavioral biology of killer whales. New York: Alan R. Liss, Inc., pp. 35–68.Google Scholar
Matkin, C.O., Saulitis, E.L., Ellis, G.M., Olesiuk, P. and Rice, S.D. (2008) Ongoing population-level impacts on killer whales Orcinus orca following th ‘Exxon Valdez’ oil spill in Prince William Sound, Alaska. Marine Ecology Progress Series 356, 269–281.CrossRefGoogle Scholar
Morin, P.A.Archer, F.I., Foote, A.D., Vilstrup, J., Allen, E.E., Wade, P., Durban, J., Parsons, K., Pitman, R., Li, L., Bouffard, P., Abel Nielsen, S.C., Rasmussen, M., Willerslev, E., Gilbert, M.T.P. and Harkins, T. (2010) Complete mitochondrial genome phylogeographic analysis of killer whales (Orcinus orca) indicated multiple species. Genome Research 20, 908–916.CrossRefGoogle ScholarPubMed
Morton, A.B. and Symonds, H.K. (2002) Displacement of Orcinus orca (L.) by high amplitude sound in British Columbia, Canada. International Council of the Exploration of the Sea Journal of Marine Science 59, 71–80.Google Scholar
Noren, S.R., Biedenbach, G., Redfern, J.V. and Edwards, E.F. (2008) Hitching a ride: the formation locomotion strategy of dolphin calves. Functional Ecology 22, 284–288.CrossRefGoogle Scholar
Olesiuk, P.F., Bigg, M.A. and Ellis, G.M. (1990) Life history and population dynamics of resident killer whales (Orcinus orca) in the coastal waters of British Columbia and Washington State. Report for the International Whaling Commission, Special Issue 12, 209–243.Google Scholar
Olesiuk, P.F., Ellis, G.M. and Ford, J.K.B. (2005) Life history and population dynamics of northern resident killer whales (Orcinus orca) in British Columbia. CSAS Research Document 2005/045. Nanaimo, BC: Fisheries and Oceans Canada.Google Scholar
Orellana, I. (2006) Wintering area dynamics of the Norwegian spring spawning herring, (Clupea harengus Linnaeus 1758) with emphasis on the period 1988–2005. MSc thesis. University of Bergen, Norway.Google Scholar
Otis, D.L., Burnham, K.P., White, G.C. and Anderson, D.R. (1978) Statistical inference from capture data on closed animal populations. Wildlife Monographs 62, 3–135.Google Scholar
Pilling, G., Nichols, J., Hoel, A.H., Hough, A. and Davies, S. (2009) Norwegian spring spawning herring purse-seine and pelagic trawl fisheries. Certification Report for Norges Sildesalgslog, 123 pp. Available at: http://www.msc.org/trade-a-fishery/fisheries-in-the-program/certified/north-east-atlantic/norway-spring-spawning-herring/assessment-downloads-1/Norwegion%20Spring%20Spawning%20Herring%20Final%20Report%20v4.pdf.Google Scholar
Pilot, M., Dahlheim, M.E. and Hoelzel, A.R. (2010) Social cohesion among kin, gene flow without dispersal and the evolution of population genetic structure in the killer whale (Orcinus orca). Journal of Evolutionary Biology 23, 20–31.CrossRefGoogle ScholarPubMed
Pitman, R.L. and Ensor, P. (2003) Three forms of killer whales (Orcinus orca) in Antarctic waters. Journal of Cetacean Research and Management 5, 131–139.CrossRefGoogle Scholar
Pledger, S., Pollock, K.H. and Norris, J.L. (2003) Open capture–recapture models with heterogeneity: I. Cormack–Jolly–Seber Model. Biometrics 59, 786–794.CrossRefGoogle ScholarPubMed
Pollock, K.H., Nichols, J.D., Brownie, C. and Hines, J.E. (1990) Statistical inference for capture–recapture experiments. Wildlife Monographs 107, 3–97.Google Scholar
Poncelet, É., Barbraud, C. and Guinet, C. (2010) Population dynamics of killer whales (Orcinus orca) in the Crozet Archipelago, southern Indian Ocean: a mark–recapture study from 1977 to 2002. Journal of Cetacean Research and Management 11, 41–48.CrossRefGoogle Scholar
Pradel, R. (1993) Flexibility in survival analysis from recapture data: handling trap-dependence. In Lebreton, J.-D. and North, P.M. (eds) Marked individuals in the study of bird population. Basel: Birkhäuser Verlag, pp. 29–37.Google Scholar
Pradel, R. and Sanz-Aguilar, A. (2012) Modeling trap-awareness and related phenomena in capture-recapture studies. PloS ONE 7, p.e32666.CrossRefGoogle ScholarPubMed
Pradel, R., Hines, J.E., Lebreton, J.-D. and Nichols, J.D. (1997) Capture–recapture survival models taking account of transients. Biometrics 53, 60–72.CrossRefGoogle Scholar
R Development Core Team (2012) R: A language and environment for statistical computing. Vienna: R Foundation for Statistical Computing. Available at: http://www.r-project.org/ (accessed 30 June 2013).Google Scholar
Ramp, C., Bérubé, M., Hagen, W. and Sears, R. (2006) Survival of adult blue whales Balaenoptera musculus in the Gulf of St Lawrence, Canada. Marine Ecology Progress Series 319, 287–295.CrossRefGoogle Scholar
Ramp, C., Bérubé, M., Palsbøll, P., Hagen, W. and Sears, R. (2010) Sex-specific survival in the humpback whale Megaptera novaeangliae in the Gulf of St Lawrence, Canada. Marine Ecology Progress Series 400, 267–276.CrossRefGoogle Scholar
Reisinger, R.R., de Bruyn, P.J.N. and Bester, M.N. (2011b) Abundance estimates of killer whales at subantarctic Marion Island. Aquatic Biology 12, 177–185.CrossRefGoogle Scholar
Reisinger, R.R., de Bruyn, P.J.N., Tosh, C.A., Oosthuizen, W.C., Mufanadzo, N.T. and Bester, M.N. (2011a) Prey and seasonal abundance of killer whales at sub-Antarctic Marion Island. African Journal of Marine Science 33, 99–105.CrossRefGoogle Scholar
Ross, P.S., Ellis, G.M., Ikonomou, M.G., Barrett-Lennard, L.G. and Addison, R.F. (2000) High PCB concentrations in free-ranging Pacific killer whales, Orcinus orca: effects of age, sex and dietary preference. Marine Pollution Bulletin 40, 504–515.CrossRefGoogle Scholar
Sandland, R.L. and Kirkwood, G.P. (1981) Estimation of survival in marked populations with possibly dependent sighting probabilities. Biometrika 68, 531–541.CrossRefGoogle Scholar
Schwarz, C.J. and Seber, G.A.F. (1999) Estimating animal abundance: review III. Statistical Science 14, 427–456.CrossRefGoogle Scholar
Seber, G.A.F. (1965) A note on the multiple-recapture census. Biometrika 52, 249–259.CrossRefGoogle ScholarPubMed
Similä, T. (1997a) Behavioral ecology of killer whales in northern Norway. PhD thesis. University of Tromsø, Norway.Google Scholar
Similä, T. (1997b) Sonar observations of killer whales (Orcinus orca) feeding on herring schools. Aquatic Mammals 23, 119–126.Google Scholar
Similä, T. (2005) Interactions between herring fishery and killer whales in northern Norway. International Council for the Exploration of the Sea (CM Papers and Reports), CM 2005/R:03.Google Scholar
Similä, T. and Christensen, I. (1992) Seasonal distribution and abundance of killer whales around Lofoten and Vesterålen Islands, Northern Norway. International Council for the Exploration of the Sea (CM Papers and Reports), CM 1992/N:11.Google Scholar
Similä, T. and Lindblom, L. (1993) Persistence of natural markings on photographically identified killer whales (Orcinus orca). International Council for the Exploration of the Sea (CM Papers and Reports), CM 1993/N:12.Google Scholar
Similä, T. and Ugarte, F. (1993) Surface and underwater observations of cooperatively feeding killer whales in northern Norway. Canadian Journal of Zoology 71, 1494–1499.CrossRefGoogle Scholar
Similä, T., Holst, J.C. and Christensen, I. (1996) Occurrence and diet of killer whales in northern Norway: season patterns relative to the distribution and abundance of Norwegian spring-spawning herring. Canadian Journal of Fisheries and Aquatic Sciences 53, 769–779.CrossRefGoogle Scholar
Stenersen, J. and Similä, T. (2004) Norwegian killer whales. Henninsvaer: Tringa Forlag.Google Scholar
Tixier, P., Gasco, N., Duhamel, G., Vivant, M., Authier, M. and Guinet, C. (2010) Interactions of Patagonian toothfish fisheries with killer and sperm whales in the Crozet Islands Exclusive Economic Zone: an assessment of depredation levels and insights on possible mitigation strategies. CCAMLR Science 17, 179–195.Google Scholar
Toresen, R. and Østvedt, O.J. (2000) Variation in abundance of Norwegian spring-spawning herring (Clupea harengus, Clupeidae) throughout the 20th century and the influence of climatic fluctuations. Fish and Fisheries 1, 231–256.Google Scholar
Visser, I. (1999) Benthic foraging on stingrays by killer whales (Orcinus orca) in New Zealand waters. Marine Mammal Science 15, 220–227.CrossRefGoogle Scholar
Ward, E.J., Holmes, E.E. and Balcomb, K.C. (2009) Quantifying the effects of prey abundance on killer whale reproduction. Journal of Applied Ecology 46, 632–640.CrossRefGoogle Scholar
Ward, E.J., Semmens, B.E., Holmes, E.E. and Balcolm, K.C. III (2011) Effects of multiple levels of social organization on survival and abundance. Conservation Biology 25, 350–355.Google ScholarPubMed
Wilson, B., Hammond, P.S. and Thompson, P.M. (1999) Estimating size and assessing trends in a coastal bottlenose dolphin population. Ecological Applications 9, 288–300.CrossRefGoogle Scholar
Wolkers, H., Corkeron, P.J., Van Parijs, S., Similä, T. and Van Bavel, B. (2007) Accumulation and transfer of contaminants in killer whales (Orcinus orca) from Norway: indications for contaminant metabolism. Environmental Toxicology and Chemistry 26, 1582–1590.CrossRefGoogle ScholarPubMed
Zerbini, A.N., Waite, J.M., Durban, J.W., LeDuc, R., Dahlheim, M.E. and Wade, P.R. (2007) Estimating abundance of killer whales in nearshore waters of the Gulf of Alaska and Aleutian Islands using line-transect sampling. Marine Biology 150, 1033–1045.CrossRefGoogle Scholar
Øien, N. (1993) Abundance of killer whales (Orcinus orca) in waters off Norway. The North Atlantic Marine Mammal Commission (Working Group Report), SC-WG/NBK1/4.Google Scholar
Øien, N. (1988) The distribution of killer whales (Orcinus orca) in the North Atlantic based on Norwegian catches, 1938–1981, and incidental sightings, 1967–1987. In Sigurjónsson, J. and Leatherwood, S. (eds) North Atlantic killer whale. Rit Fiskideildar 11, 5–78.Google Scholar
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