Published February 24, 2016 | Version v1
Journal article Open

Summer diving and haul-out behavior of leopard seals (Hydrurga leptonyx) near mesopredator breeding colonies at Livingston Island, Antarctic Peninsula

Description

Krause, Douglas J., Goebel, Michael E., Marshall, Greg J., Abernathy, Kyler (2016): Summer diving and haul-out behavior of leopard seals (Hydrurga leptonyx) near mesopredator breeding colonies at Livingston Island, Antarctic Peninsula. Marine Mammal Science 32 (3): 839-867, DOI: 10.1111/mms.12309, URL: http://dx.doi.org/10.1111/mms.12309

Files

source.pdf

Files (881.8 kB)

Name Size Download all
md5:5fbe5f42c0703539dbdb12e0357ea220
881.8 kB Preview Download

Linked records

Additional details

Identifiers

LSID
urn:lsid:plazi.org:pub:FFBE5F42C0703539FFDBFFE0357EA220

References

  • Agostinelli, C., and U. Lund. 2011. R package 'circular': Circular statistics. Available at https://r-forge.r-project.org/projects/circular/.
  • Ainley, D. G., G. Ballard, B. J. Karl and K. M. Dugger. 2005. Leopard seal predation rates at penguin colonies of different size. Antarctic Science 17:335-340.
  • Albrecht, M., and N. J. Gotelli. 2001. Spatial and temporal niche partitioning in grassland ants. Oecologia 126:134-141.
  • Asaga, T., Y. Naito, B. J. Le Boeuf and H. Sakurai. 1994. Functional analysis of dive types of female northern elephant seals. Pages 310-327 in B. Le Boeuf and R. Laws, eds. Elephant seals: Population ecology, behavior and physiology. University of California Press, Berkeley, CA.
  • ATCM. 2011. Management Plan for Antarctic Specially Protected Area No. 149: Measure 7 Annex. Pages 439-462 in Final Report of the Thirty-fourth Antarctic Treaty Consultative Meeting (ATCM). Secretariat of the Antarctic Treaty, Buenos Aires, Argentina.
  • Baechler, J., C. A. Beck and W. D. Bowen. 2002. Dive shapes reveal temporal changes in the foraging behaviour of different age and sex classes of harbour seals (Phoca vitulina). Canadian Journal of Zoology 80:1569-1577.
  • Bengtson, J., and B. Stewart. 1992. Diving and haulout behavior of crabeater seals in the Weddell Sea, Antarctica, during March 1986. Polar Biology 12:635-644.
  • Bertram, B. C. R. 1979. Serengeti predators and their social systems. Pages 221-248 in A. R. E. Sinclair and M. Norton-Griffiths, eds. Serengeti: Dynamics of an ecosystem. University of Chicago Press, Chicago, IL.
  • Bester, M., N. N. Aacute, A. W. Erickson and J. W. H. Ferguson. 1995. Seasonal change in the distribution and density of seals in the pack ice off Princess Martha Coast, Antarctica. Antarctic Science 7:357-364.
  • Bester, M. N., J. W. H. Ferguson and F. C. Jonker. 2002. Population densities of pack ice seals in the Lazarev Sea, Antarctica. Antarctic Science 14:123-127.
  • Bonner, W. 1990. The natural history of seals. Facts on File, New York, NY.
  • Bonner, W. N. 1994. Seals and sea lions of the world. Blandford, London, U.K..
  • Borsa, P. 1990. Seasonal occurrence of the leopard seal, Hydrurga leptonyx, in the Kerguelen Islands. Canadian Journal of Zoology 68:405-408.
  • Boveng, P., L. Hiruki, M. Schwartz and J. Bengtson. 1998. Population growth of Antarctic fur seals: Limitation by a top predator, the leopard seal? Ecology 79:2863-2877.
  • Bowen, W., D. Tully, D.J. Boness, B.M. Bulheier and G. J. Marshall. 2002. Prey-dependent foraging tactics and prey profitability in a marine mammal. Marine Ecology Progress Series 244:235-245.
  • Boyd, I. L., J. P. Y. Arnould, T. Barton and J. P. Croxall. 1994. Foraging behaviour of Antarctic fur seals during periods of contrasting prey abundance. Journal of Animal Ecology 63:703-713.
  • Breiman, L. 2001. Random Forests. Machine Learning 45:5-32.
  • Breiman, L. 2003. Setting up, using, and understanding Random Forests. Version 4:1-32.
  • Burns, J. M., M. A. Castellini and J. F. Schreer. 1997. Physiological effects on dive patterns and foraging strategies in yearling Weddell seals (Leptonychotes weddellii). Canadian Journal of Zoology 75:1796-1810.
  • Burns, J. M., D. P. Costa, M. A. Fedak, et al. 2004. Winter habitat use and foraging behavior of crabeater seals along the Western Antarctic Peninsula. Deep Sea Research Part II: Topical Studies in Oceanography 51:2279-2303.
  • Calinski, T., and J. Harabasz. 1974. A dendrite method for cluster analysis. Communications in Statistics 3:1-27.
  • Casaux, R., A. Baroni, A. Ramon, A. Carlini, M. Bertolin and C. Diprinzio. 2009. Diet of the leopard seal (Hydrurga leptonyx) at the Danco Coast, Antarctic Peninsula. Polar Biology 32:307-310.
  • Costa, D. P., and N. J. Gales. 2003. Energetics of a benthic diver: Seasonal foraging ecology of the Australian sea lion, Neophoca cinerea. Ecological Monographs 73:27-43.
  • Crocker, D. E., B. J. Le Boeuf and D. P. Costa. 1997. Drift diving in female northern elephant seals: Implications for food processing. Canadian Journal of Zoology 75:27-39.
  • Davis, R., L. Fuiman, T. Williams, M. Horning and W. Hagey. 2003. Classification of Weddell seal dives based on 3-dimensional movements and video-recorded observations. Marine Ecology Progress Series 264:109-122.
  • Davis, R. W., L. A. Fuiman, K. M. Madden and T. M. Williams. 2013. Classification and behavior of free-ranging Weddell seal dives based on three-dimensional movements and video-recorded observations. Deep Sea Research Part II: Topical Studies in Oceanography 88-89:65-77.
  • Devault, T. L., J. O. E. Rhodes and J. A. Shivik. 2003. Scavenging by vertebrates: Behavioral, ecological, and evolutionary perspectives on an important energy transfer pathway in terrestrial ecosystems. Oikos 102:225-234.
  • Dowd, M., and R. Joy. 2010. Estimating behavioral parameters in animal movement models using a state-augmented particle filter. Ecology 92:568-575.
  • Drabek, C. M. 1975. Some anatomical aspects of the cardiovascular system of Antarctic seals and their possible functional significance in diving. Journal of Morphology 145:85-105.
  • Erickson, A. W., and M. B. Hanson. 1990. Continental estimates and population trends of Antarctic ice seals. Pages 253-264 in K. R. Kerry and G. Hempel, eds. Antarctic ecosystems. Springer-Verlag, Berlin, Germany.
  • Erickson, A. W., and R. J. Hofman. 1974. Antarctic seals. Antarctic Map Folio Series Folio 18:4-13.
  • Everitt, B. S., and T. Hothorn. 2010. A handbook of statistical analysis using R. Taylor and Frances Group, LLC, Boca Raton, FL.
  • Fedak, M. A., P. Lovell and S. M. Grant. 2001. Two approaches to compressing and interpreting time-depth information as collected by time-depth recorders and satellite-linked data recorders. Marine Mammal Science 17:94-110.
  • Forcada, J., and S. Robinson. 2006. Population abundance, structure and turnover estimates for leopard seals during winter dispersal combining tagging and photo-identification data. Polar Biology 29:1052-1062.
  • Forcada, J., and P. Trathan. 2008. Abundance estimates for crabeater, Weddell and leopard seals at the Antarctic Peninsula and in the western Weddell Sea (90°-30°W, 60°-80°S). Document WG-EMM-PSW-08/6. CCAMLR, Hobart, Australia. 9 pp.
  • Forcada, J., D. Malone, J. Royle and I. Staniland. 2009. Modelling predation by transient leopard seals for an ecosystem-based management of Southern Ocean fisheries. Ecological Modelling 220:1513-1521.
  • Forcada, J., P. N. Trathan, P. L. Boveng, et al. 2012. Responses of Antarctic pack-ice seals to environmental change and increasing krill fishing. Biological Conservation 149:40-50.
  • Fox, J., and S. Weisberg. 2011. An R companion to applied regression. Sage, Thousand Oaks, CA.
  • Frost, K. J., M. A. Simpkins and L. F. Lowry. 2001. Diving behavior of subadult and adult harbor seals in Prince William Sound, Alaska. Marine Mammal Science 17:813-834.
  • Gales, N. J. 1989. Chemical restraint and anesthesia of pinnipeds: A review. Marine Mammal Science 5:228-256.
  • Gilbert, J., and A. Erickson. 1977. Distribution and abundance of seals in the pack ice of the Pacific sector of the Southern Ocean. Pages 703-740 in A. Llano, ed. Adaptations within Antarctic ecosystems. Smithsonian Institution, Washington, DC.
  • Goebel, M. E., D. P. Costa, D. E. Crocker, J. E. Sterling and D. A. Demer. 2000. Foraging ranges and dive patterns in relation to bathymetry and time-of-day of Antarctic fur seals, Cape Shirreff, Livingston Island Antarctica. Pages 47-50 in W. Davisons, C. Howard-Williams and P. Broady, eds. Antarctic ecosystems: Models for wider ecological understanding. New Zealand Natural Sciences Press, Christchurch, New Zealand.
  • Grolemund, G., and H. Wickham. 2011. Dates and times made easy with lubridate. Journal of Statistical Software 40:1-25.
  • Hall-Aspland, S. A., and T. L. Rogers. 2004. Summer diet of leopard seals (Hydrurga leptonyx) in Prydz Bay, Eastern Antarctica. Polar Biology 27:729-734.
  • Hamilton, J. E. 1939. The leopard seal Hydrurga leptonyx (De Blainville). Discovery Reports 18:239-264.
  • Hanuise, N., C. A. Bost, W. Huin, A. Auber, L. G. Halsey and Y. Handrich. 2010. Measuring foraging activity in a deep-diving bird: Comparing wiggles, oesophageal temperatures and beak-opening angles as proxies of feeding. The Journal of Experimental Biology 213:3874-3880.
  • Harmsen, B. J., R. J. Foster, S. C. Silver, L. E. T. Ostro and C. P. Doncaster. 2009. Spatial and temporal interactions of sympatric jaguars (Panthera onca) and pumas (Puma concolor) in a neotropical forest. Journal of Mammalogy 90:612-620.
  • Hass, C. C. 2009. Competition and coexistence in sympatric bobcats and pumas. Journal of Zoology 278:174-180.
  • Hastie, T., R. Tibshirani and J. Friedman. 2009. The elements of statistical learning. Springer, New York, NY.
  • Higgins, D. P., T. L. Rogers, A. D. Irvine and S. A. Hall-Aspland. 2002. Use of midazolam/ pethidine and tiletamine/zolazepam combinations for the chemical restraint of leopard seals (Hydrurga leptonyx). Marine Mammal Science 18:483-499.
  • Hindell, M., D. Slip and H. Burton. 1991. The diving behavior of adult male and female southern elephant seals, Mirounga leonina (Pinnipedia, Phocidae). Australian journal of Zoology 39:595-619.
  • Hiruki, L., M. Schwartz and P. Boveng. 1999. Hunting and social behaviour of leopard seals (Hydrurga leptonyx) at Seal Island, South Shetland Islands, Antarctica. Journal of Zoology 249:97-109.
  • Hofman, R., R. Reichle, D. Siniff and D. Muller-Schwarze. 1977. The leopard seal (Hydrurga leptonyx) at Palmer station, Antarctica. Pages 769-782 in G. Llano ed. Adaptations within Antarctic ecosystems. Proceedings of the 3rd Scientific Committee on Antarctic Research Symposium on Antarctic Biology. Smithsonian Institution, Washington, DC.
  • Hooker, S. K., I. L. Boyd, M. Jessopp, O. Cox, J. Blackwell, P. L. Boveng and J. L. Bengtson. 2002. Monitoring the prey-field of marine predators: Combining digital imaging with datalogging tags. Marine Mammal Science 18:680-697.
  • Hubbard, R. 1968. Husbandry and laboratory care of pinnipeds. Pages 299-358 in R. Harrison, ed. The behavior and physiology of pinnipeds. Appleton-Century-Crofts, New York, NY.
  • James, D., and K. Hornik. 2013. chron: Chronological objects which can handle dates and times in R. Available at https://cran.r-project.org/web/packages/chron/index.html (version 2.3-45 accessed April 2015).
  • Jansen, J. K., P. L. Boveng and J. L. Bengtson. 1998. Foraging modes of chinstrap penguins: Contrasts between day and night. Marine Ecology Progress Series 165:161-172.
  • Jay, C. V., S. D. Farley and G. W. Garner. 2001. Summer diving behavior of male walruses in Bristol Bay, Alaska. Marine Mammal Science 17:617-631.
  • Jessopp, M. J., J. Forcada, K. Reid, P. N. Trathan and E. J. Murphy. 2004. Winter dispersal of leopard seals (Hydrurga leptonyx): Environmental factors influencing demographics and seasonal abundance. Journal of Zoology 263:251-258.
  • Johnson, W., T. Fuller and W. Franklin. 1996. Sympatry in canids: A review and assessment. Pages 189-218 in J. L. Gittleman, ed. Carnivore behavior, ecology, and evolution. Cornell University Press, Ithaca, NY.
  • Kooyman, G. L. 1965. Leopard seals of Cape Crozier. Animals 6:58-63.
  • Kooyman, G. L. 1966. Maximum diving capacities of the Weddell seal, Leptonychotes weddelli. Science 151:1553-1554.
  • Kooyman, G. L. 1981. Leopard seal (Hydrurga leptonyx De Blainville, 1820). Pages 261-272 in S. Ridgway and R. Harrison, eds. Handbook of marine mammals. Academic Press, London, U.K.
  • Kooyman, G. L. 1989. Diverse divers: Physiology and behavior. Springer-Verlag, New York, NY.
  • Kooyman, G. L. 2004. Genesis and evolution of bio-logging devices: 1963-2002. Memoirs of the National Institute of Polar Research 58:15-22.
  • Kooyman, G. L., D. Croll, S. Stone and S. Smith. 1990. Emperor penguin colony at Cape Washington, Antarctica. Polar Record 26:103-108.
  • Kotler, B. P., J. S. Brown and A. Subach. 1993. Mechanisms of species coexistence of optimal foragers: Temporal partitioning by two species of sand dune gerbils. Oikos:548-556.
  • Kozlowski, A. J., E. M. Gese and W. M. Arjo. 2008. Niche overlap and resource partitioning between sympatric kit foxes and coyotes in the Great Basin Desert of western Utah. The American Midland Naturalist 160:191-208.
  • Krause, D. J., M. E. Goebel, G. J. Marshall and K. Abernathy. 2015. Novel foraging strategies observed in a growing leopard seal (Hydrurga leptonyx) population at Livingston Island, Antarctic Peninsula. Animal Biotelemetry 3:24.
  • Kuhn, C., B. McDonald, S. Shaffer, J. Barnes, D. Crocker, J. Burns and D. Costa. 2006. Diving physiology and winter foraging behavior of a juvenile leopard seal (Hydrurga leptonyx). Polar Biology 29:303-307.
  • Laws, R. 1984. Seals. Pages 621-716 in R. M. Laws, ed. Antarctic ecology. Academic Press, Cambridge, England.
  • Le Boeuf, B. J., D. P. Costa, A. C. Huntley and S. D. Feldkamp. 1988. Continuous, deep diving in female northern elephant seals, Mirounga angustirostris. Canadian Journal of Zoology 66:446-458.
  • Le Boeuf, B. J., Y. Naito, T. Asaga, D. Crocker and D. P. Costa. 1992. Swim speed in a female northern elephant seal: Metabolic and foraging implications. Canadian Journal of Zoology 70:786-795.
  • Lennert-Cody, C. E., and R. A. Berk. 2007. Statistical learning procedures for monitoring regulatory compliance: An application to fisheries data. Journal of the Royal Statistical Society: Series A (Statistics in Society) 170:671-689.
  • Liaw, A., and M. Wiener. 2002. Classification and regression by randomForest. R News 2:18- 22.
  • Linnell, J. D. C., and O. Strand. 2000. Interference interactions, co-existence and conservation of mammalian carnivores. Diversity and Distributions 6:169-176.
  • Litvaitis, J. A., and D. J. Harrison. 1989. Bobcat-coyote niche relationships during a period of coyote population increase. Canadian Journal of Zoology 67:1180-1188.
  • Luque, S. P. 2007. Diving behaviour analysis in R. R News 7:8-14.
  • Lydersen, C., and K. M. Kovacs. 1993. Diving behaviour of lactating harp seal, Phoca groenlandica, females from the Gulf of St Lawrence, Canada. Animal Behaviour 46:1213- 1221.
  • Madden, K., L. Fuiman, T. Williams and R. Davis. 2008. Identification of foraging dives in free-ranging Weddell seals Leptonychotes weddellii: Confirmation using video records. Marine Ecology Progress Series 365:263-275.
  • Mader, T. R. 1998. Temporal variation in leopard seal presence and predation near an Antarctic penguin rookery. M.S. thesis, Montana State University, Bozeman, MT. 46 pp.
  • Major, J. T., and J. A. Sherburne. 1987. Interspecific relationships of coyotes, bobcats, and red foxes in western Maine. The Journal of Wildlife Management 51:606-616.
  • Marshall, G. J., M. Bakhtiari and M. Shepard. 2007. An advanced solid-state animal-borne video and environmental data-logging device ("Crittercam") for marine research. Marine Technology Society Journal 41:31-38.
  • Massom, R. A., and S. E. Stammerjohn. 2010. Antarctic sea ice change and variability: Physical and ecological implications. Polar Science 4:149-186.
  • Mattisson, J., J. Persson, H. Andren and P. Segerstr€ om. 2011. Temporal and spatial interactions between an obligate predator, the Eurasian lynx (Lynx lynx), and a facultative scavenger, the wolverine (Gulo gulo). Canadian Journal of Zoology 89:79-89.
  • McConnell, B. J., C. Chambers and M. A. Fedak. 1992. Foraging ecology of southern elephant seals in relation to the bathymetry and productivity of the Southern Ocean. Antarctic Science 4:393-398.
  • McGarigal, K., S. Cushman and S. G. Stafford. 2000. Multivariate statistics for wildlife and ecology research. Springer-Verlag, New York, NY.
  • Meade, J., M. Ciaglia, D. Slip, J. Negrete, M. Marquez, J. Mennucci and T. Rogers. 2015. Spatial patterns in activity of leopard seals Hydrurga leptonyx in relation to sea ice. Marine Ecology Progress Series 521:265-275.
  • Miller, A. K., M. A. Kappes, S. G. Trivelpiece and W. Z. Trivelpiece. 2010. Foraging-niche separation of breeding gentoo and chinstrap penguins, South Shetland Islands, Antarctica. The Condor 112:683-695.
  • Mills, M., and H. Biggs. 1993. Prey apportionment and related ecological relationships between large carnivores in Kruger National Park. Symposium of the Zoological Society of London 65:253-268.
  • Muller-Schwarze, D. 1984. The behavior of penguins. State University of New York Press, Albany, NY.
  • Nordoy, E. and A. Blix. 2009. Movements and dive behaviour of two leopard seals (Hydrurga leptonyx) off Queen Maud Land, Antarctica. Polar Biology 32:263-270.
  • Oksanen, J., F. Guillaume-Blanchet, R. Kindt, et al. 2013. Vegan: Community ecology package in R. Available at https://cran.r-project.org/web/packages/vegan/index.html (version 2.2-0 accessed January 2015).
  • Palomares, F., and T. M. Caro. 1999. Interspecific killing among mammalian carnivores. The American Naturalist 153:492-508.
  • Parrish, F. A., G. J. Marshall, B. Buhleier and G. A. Antonelis. 2008. Foraging interaction between monk seals and large predatory fish in the Northwestern Hawaiian Islands. Endangered Species Research 4:299-308.
  • Pena, E. A., and E. H. Slate. 2014. Gvlma: Global validation of linear model assumptions in R. Available at https://cran.r-project.org/web/packages/gvlma/index.html (version 1.0.0.2 accessed July 2015).
  • Penney, R. L., and G. Lowry. 1967. Leopard seal predation of Adelie penguins. Ecology 48:878-882.
  • Pussini, N., and M. E. Goebel. 2015. A safer protocol for field immobilization of leopard seals (Hydrurga leptonyx). Marine Mammal Science 31:1549-1558.
  • R Core Team. 2015. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria.
  • Ray, C. 1966. Snooping on seals for science. Animal Kingdom 69:66-75.
  • Revilla, E., and F. Palomares. 2001. Differences in key habitat use between dominant and subordinate animals: Intraterritorial dominance payoffs in Eurasian badgers? Canadian Journal of Zoology 79:165-170.
  • Rogers, T. L. 2007. Age-related differences in the acoustic characteristics of male leopard seals, Hydrurga leoptonyx. The Journal of the Acoustical Society of America 122:596-605.
  • Rogers, T. L. 2009. The leopard seal, Hydrurga leptonyx. Pages 673-674 in W. F. Perrin, B. Wursig and J. G. M. Thewissen eds. Encyclopedia of Marine Mammals. Academic Press, San Diego, CA.
  • Rogers, T. L. 2014. Source levels of the underwater calls of a male leopard seal. The Journal of the Acoustical Society of America 136:1495-1498.
  • Rogers, T., and M. M. Bryden. 1995. Predation of Adelie penguins (Pygoscelis adeliae) by leopard seals (Hydrurga leptonyx) in Prydz Bay, Antarctica. Canadian Journal of Zoology 73:1001-1004.
  • Rogers, T. L., D. H. Cato and M. M. Bryden. 1996. Behavioral significance of underwater vocalizations of captive leopard seals, Hydrurga leptonyx. Marine Mammal Science 12:414-427.
  • Rogers, T. L., and M. M. Bryden. 1997. Density and haul-out behavior of leopard seals (Hyrdrurga leptonyx) in Prydz Bay, Antarctica. Marine Mammal Science 13:293-302.
  • Rogers, T. L., C. J. Hogg and A. Irvine. 2005. Spatial movement of adult leopard seals (Hydrurga leptonyx) in Prydz Bay, Eastern Antarctica. Polar Biology 28:456-463.
  • Rogers, T. L., M. B. Ciaglia, H. Klinck and C. Southwell. 2013. Density can be misleading for low-density species: Benefits of passive acoustic monitoring. PLOS ONE 8:e52542.
  • Rudzinski, D. R., H. B. Graves, A. B. Sargeant and G. L. Storm. 1982. Behavioral interactions of penned red and Arctic foxes. The Journal of Wildlife Management 46:877-884.
  • Sala, J., F. Quintana, R. Wilson, J. Dignani, M. Lewis and C. Campagna. 2011. Pitching a new angle on elephant seal dive patterns. Polar Biology 34:1197-1209.
  • Santora, J. A., C. S. Reiss, V. J. Loeb and R. R. Veit. 2010. Spatial association between hotspots of baleen whales and demographic patterns of Antarctic krill Euphausia superba suggests size-dependent predation. Marine Ecolology Progress Series 405:255-269.
  • Schmidt, K., W. Je L drzejewski, H. Okarma and R. Kowalczyk. 2009. Spatial interactions between grey wolves and Eurasian lynx in Bialowie za _ Primeval Forest, Poland. Ecological Research 24:207-214.
  • Schoener, T. W. 1983. Field experiments on interspecific competition. The American Naturalist 122:240-285.
  • Schreer, J., and J. Testa. 1995. Statistical classification of diving behavior. Marine Mammal Science 11:85-93.
  • Schreer, J. F., and J. W. Testa. 1996. Classification of Weddell seal diving behavior. Marine Mammal Science 12:227-250.
  • Schreer, J. F., R. J. O'Hara Hines and K. M. Kovacs. 1998. Classification of dive profiles: A comparison of statistical clustering techniques and unsupervised artifical neural networks. Journal of Agricultural, Biological, and Environmental Statistics 3:383-404.
  • Schreer, J. F., K. M. Kovacs and R. J. O'Hara Hines. 2001. Comparative diving patterns of pinnipeds and seabirds. Ecological Monographs 71:137-162.
  • Schusterman, R. 2000. Why pinnipeds don't echolocate. The Journal of the Acoustical Society of America 107:2256-2264.
  • Scognamillo, D., I. E. Maxit, M. Sunquist and J. Polisar. 2003. Coexistence of jaguar (Panthera onca) and puma (Puma concolor) in a mosaic landscape in the Venezuelan llanos. Journal of Zoology 259:269-279.
  • Shirihai, H. 2002. The complete guide to Antarctic wildlife. Princeton University Press, Princeton, NJ.
  • Simpkins, M. A., B. P. Kelly and D. Wartzok. 2001. Three-dimensional diving behaviors of ringed seals (Phoca hispida). Marine Mammal Science 17:909-925.
  • Siniff, D. B., and S. Stone. 1985. The role of the leopard seal in the tropho-dynamics of the Antarctic marine ecosystem. Pages 555-560 in W. R. Siegfried, P. R. Condy and R. M. Laws, eds. Antarctic nutrient cycles and food webs. Springer Verlag, Berlin, Germany.
  • Southwell, C., K. Knowles, P. Ensor, E. J. Woehler and T. L. Rogers. 2003. The timing of pupping by pack-ice seals in East Antarctica. Polar Biology 26:648-652.
  • Southwell, C., C. G. M. Paxton, D. Borchers, P. Boveng, T. Rogers and W. K. De La Mare. 2008. Uncommon or cryptic? Challenges in estimating leopard seal abundance by conventional but state-of-the-art methods. Deep Sea Research Part I: Oceanographic Research Papers 55:519-531.
  • Southwell, C., J. Bengtson, M. Bester, et al. 2012. A review of data on abundance, trends in abundance, habitat use and diet of ice-breeding seals in the Southern Ocean. CCAMLR Science 19:49-74.
  • Stirling, I. 1974. Midsummer observations on the behavior of wild polar bears (Ursus maritimus). Canadian Journal of Zoology 52:1191-1198.
  • Stirling, I., and D. B. Siniff. 1979. Underwater vocalizations of leopard seals (Hydrurga leptonyx) and crabeater seals (Lobodon carcinophagus) near the South Shetland Islands, Antarctica. Canadian Journal of Zoology 57:1244-1248.
  • Svanb€ ack, R., and D. I. Bolnick. 2005. Intraspecific competition affects the strength of individual specialization: An optimal diet theory method. Evolutionary Ecology Research 7:993-1012.
  • Svanb€ ack, R., and D. I. Bolnick. 2007. Intraspecific competition drives increased resource use diversity within a natural population. Proceedings of the Royal Society of London B: Biological Sciences 274:839-844.
  • Sweeney, J. 1974. Procedures for clinical management of pinnipeds. Journal of the American Veterinary Medical Association 165:811-814.
  • Thums, M., C. J. A. Bradshaw and M. A. Hindell. 2008. A validated approach for supervised dive classification in diving vertebrates. Journal of Experimental Marine Biology and Ecology 363:75-83.
  • Tinker, M. T., D. P. Costa, J. A. Estes and N. Wieringa. 2007. Individual dietary specialization and dive behaviour in the California sea otter: Using archival time-depth data to detect alternative foraging strategies. Deep Sea Research Part II: Topical Studies in Oceanography 54:330-342.
  • Townsend, C. R., M. Begon and J. L. Harper. 2008. Essentials of ecology. Wiley-Blackwell Publishing, Malden, MA.
  • Trivelpiece, W., J. Bengtson, S. Trivelpiece and N. Volkman. 1986. Foraging behavior of gentoo and chinstrap penguins as determined by new radiotelemetry techniques. The Auk 103:777-781.
  • Trivelpiece, W. Z., S. G. Trivelpiece and N. J. Volkman. 1987. Ecological segregation of Adelie, gentoo, and chinstrap penguins at King George Island, Antarctica. Ecology 68:351-361.
  • Van Orsdol, K. G. 1984. Foraging behaviour and hunting success of lions in Queen Elizabeth National Park, Uganda. African Journal of Ecology 22:79-99.
  • Venables, W. N., and B. D. Ripley. 2002. Modern applied statistics with S. Springer, New York, NY.
  • Vera, C., R. Vargas and D. N. Torres. 2005. Estrategias depredatorias del la foca leopardo sobre cachorros de lobo fino Antarctico [Predatory strategies of leopard seals on Antarctic fur seal pups]. Boletin Antarctico Chileno 24:12-17.
  • Verikas, A., A. Gelzinis and M. Bacauskiene. 2011. Mining data with random forests: A survey and results of new tests. Pattern Recognition 44:330-349.
  • Villegas-Amtmann, S., J. W. E. Jeglinski, D. P. Costa, P. W. Robinson and F. Trillmich. 2013. Individual foraging strategies reveal niche overlap between endangered Galapagos pinnipeds. PLOS ONE 8:e70748.
  • Viviant, M., P. Monestiez and C. Guinet. 2014. Can we predict foraging success in a marine predator from dive patterns only? Validation with prey capture attempt data. PLOS ONE 9:e88503.
  • Walker, T., I. Boyd, D. McCafferty, R. Taylor and K. Reid. 1998. Seasonal occurrence and diet of leopard seals (Hydrurga leptonyx) at Bird Island, South Georgia. Antarctic Science 10:75-81.
  • Warren, J. D., and D. A. Demer. 2010. Abundance and distribution of Antarctic krill (Euphausia superba) nearshore of Cape Shirreff, Livingston Island, Antarctica, during six austral summers between 2000 and 2007. Canadian Journal of Fisheries and Aquatic Sciences 67:1159-1170.
  • Warren, J. D., J. A. Santora and D. A. Demer. 2009. Submesoscale distribution of Antarctic krill and its avian and pinniped predators before and after a near gale. Marine Biology 156:479-491.
  • Watanabe, Y. Y., and A. Takahashi. 2013. Linking animal-borne video to accelerometers reveals prey capture variability. Proceedings of the National Academy of Sciences 110:2199-2204.
  • Weise, M. J., J. T. Harvey and D. P. Costa. 2010. The role of body size in individual-based foraging strategies of a top marine predator. Ecology 91:1004-1015.
  • Wickham, H. 2009. Ggplot2: Elegant graphics for data analysis. Springer, New York, NY.
  • Wikenros, C., O. Liberg, H. Sand and H. Andren. 2010. Competition between recolonizing wolves and resident lynx in Sweden. Canadian Journal of Zoology 88:271-279.
  • Williams, R., and M. Bryden. 1993. Observations of blood values, heart-rate and respiratory rate of leopard seals (Hydrurga leptonyx) (Carnivora, Phocidae). Australian Journal of Zoology 41:433-439.
  • Wilson, E. A. 1902. Notes on Antarctic seals. Pages 67-73 in E. Lankester, ed. Report on the collections of natural history made in the Antarctic regions during the voyage of the "Southern Cross". British Museum (Natural History), London, U.K.
  • Wilson, E. A. 1905. On the whales, seals and birds of Ross Sea and South Victoria Land. Pages 469-494 in R. Scott, ed. The Voyage of the 'Discovery'. Charles Scribner's Sons, New York, NY.
  • Wilson, E. E., and E. M. Wolkovich. 2011. Scavenging: How carnivores and carrion structure communities. Trends in Ecology and Evolution 26:129-135.