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The importance of Antarctic toothfish as prey of Weddell seals in the Ross Sea

  • David G. Ainley (a1) and Donald B. Siniff (a2)

Uncertainty exists over the importance of Antarctic toothfish (Dissostichus mawsoni) as prey of top predators in the Ross Sea. In this paper we assess relative weight given to direct, observational evidence of prey taken, as opposed to indirect evidence from scat and biochemical analysis, and conclude that toothfish are important to Weddell seals (Leptonychotes weddellii). The seals eat only the flesh of large toothfish and therefore they are not detected in scat or stomach samples; biochemical samples have been taken from seal sub-populations where toothfish seldom occur. Using direct observations of non-breeding seals away from breeding haulouts in McMurdo Sound, 0.8–1.3 toothfish were taken per day. Based on these and other data, the non-breeding portion of the McMurdo Sound seal population, during spring and summer, consume about 52 tonnes of toothfish. Too many unknowns exist to estimate the non-trivial amount consumed by breeders. We discuss why reduced toothfish availability to Weddell seals, for energetic reasons, cannot be compensated by a switch to silverfish (Pleuragramma antarcticum) or squid. The Ross Sea toothfish fishery should be reduced including greater spatial management, with monitoring of Weddell seal populations by CCAMLR. Otherwise, probable cascades will lead to dramatic changes in the populations of charismatic megafauna.

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D.G. Ainley 2007. Letter response to Ken Frank et al. ‘The ups and downs of trophic control in continental shelf ecosystems’. Trends in Ecology & Evolution, 22, 444445.

D.G. Ainley L.K. Blight 2009. Ecological repercussions of historical fish extraction from the southern ocean. Fish and Fisheries, 10, 1338.

D.G. Ainley , G. Ballard K.M. Dugger 2006a. Competition among penguins and cetaceans reveals trophic cascades in the Ross Sea, Antarctica. Ecology, 87, 20802093.

D.G. Ainley , G. Ballard , K.J. Barton , B.J. Karl , G.H. Rau , C.A. Ribic P.R. Wilson 2003. Spatial and temporal variation of diet composition and quality within a presumed metapopulation of Adélie penguins. Condor, 105, 95106.

R.D. Andrews , R.L. Pitman L.T. Ballance 2008. Satellite tracking reveals distinct movement patterns for Type B and Type C killer whales in the southern Ross Sea, Antarctica. Polar Biology, 31, 14611468.

J. Baum B. Worm 2009. Cascading top-down effects of changing oceanic predator abundances. Journal of Animal Ecology, 10.1111/j.1365-2656.2009.01531.

J.M. Burns , S.J. Trumble , M.A. Castellini J.W. Testa 1998. The diet of Weddell seals in McMurdo Sound, Antarctica silverfish determined from scat collections and stable isotope analysis. Polar Biology, 19, 272282.

I. Calhaem D.A. Christoffel 1969. Some observations of the feeding habits of a Weddell seal, and measurements of its prey, Dissostichus mawsoni, at McMurdo Sound, Antarctica. New Zealand Journal of Marine and Freshwater Research, 3, 181190.

M.F. Cameron D.B. Siniff 2004. Age-specific survival, abundance, and immigration rates of a Weddell seal (Leptonychotes weddellii) population in McMurdo Sound, Antarctica. Canadian Journal of Zoology, 82, 601615.

R.W. Davis , L.A. Fuiman , T.M. Williams , W. Horning W.P. Hagey 2003. Classification of Weddell seal dives based on 3-dimensional movements and video-recorded observations. Marine Ecology Progress Series, 264, 109122.

R.W. Davis , L.A. Fuiman , T.M. Williams , S.O. Collier , W.P. Hagey , S.B. Kanatous , S. Kohin M. Horning 1999. Hunting behavior of a marine mammal beneath the Antarctic fast ice. Science, 283, 993995.

J.H. Dearborn 1965. Food of Weddell seals at McMurdo Sound, Antarctica. Journal of Mammalogy, 46, 3743.

A.L. DeVries J.T. Eastman 1981. Physiology and ecology of notothenioid fishes of the Ross Sea, Antarctica. Journal of the Royal Society of New Zealand, 11, 329340.

J.T. Eastman 1993. Antarctic fish biology: evolution in a unique environment. San Diego, CA: Academic Press, 322 pp.

J.T. Eastman A.L. DeVries 2000. Aspects of body size and gonadal histology in the Antarctic toothish, Dissostichus mawsoni, from McMurdo Sound, Antarctica. Polar Biology, 23, 189195.

K.T. Frank , B. Petrie , J.S. Choi W.C. Leggett 2005. Trophic cascades in a formerly cod-dominated ecosystem. Science, 308, 16211623.

G.L. Hadley , J.J. Rotella R.A. Garrott 2007. Influence of maternal characteristics and oceanographic conditions on survival and recruitment probabilities of Weddell seals. Oikos, 116, 601613.

M.R. Heithaus , A. Frid , A.J. Wirsing B. Worm 2008. Predicting ecological consequences of marine top predator declines. Trends in Ecology and Evolution, 23, 202210.

K.A. Hobson R.G. Clark 1992. Assessing avian diets using stable isotopes. I: Turnover of I3C in tissues. Condor, 94, 181188.

G.L. Kooyman , D.B. Siniff , I. Stirling J.L. Bengtson 2004. Moult habitat, pre- and post-moult diet and post-moult travel of Ross Sea emperor penguins. Marine Ecology Progress Series, 267, 281290.

M.R. Krahn , R.L. Pitman , D.G. Burrows , D.P. Herman R.W. Pearce 2008. Use of chemical tracers to assess diet and persistent organic pollutants in Antarctic type C killer whales. Marine Mammal Science, 24, 643663.

S. Lake , H. Burton J. Van Den Hoff 2003. Regional, temporal and fine-scale spatial variation in Weddell seal diet at four coastal locations in east Antarctica. Marine Ecology Progress Series, 254, 293305.

M. La Mesa , J.T. Eastman J.M. Vacchi 2004. The role of notothenioid fish in the food web of the Ross Sea shelf waters: a review. Polar Biology, 27, 321338.

R.C. Murphy 1962. The oceanic life of the Antarctic. Scientific American, 207, 187210.

R.A. Myers , J.K. Baum , T.D. Shepherd , S.P. Powers C.H. Peterson 2007. Cascading effects of the loss of apex predatory sharks from a coastal ocean. Science, 315, 18461850.

H. Österblom , M. Casini , O. Olsson A. Bignert 2006. Fish, seabirds and trophic cascades in the Baltic Sea. Marine Ecology Progress Series, 323, 233238.

D.L. Phillips P.L. Koch 2002. Incorporating concentration dependence in stable isotope mixing models. Oecologia, 130, 114125.

J. Plötz 1986. Summer diet of Weddell seals (Leptonychotes weddelli) in the eastern and southern Weddell Sea, Antarctica. Polar Biology, 6, 97102.

P.A. Prince C. Ricketts 1981. Relationships between food supply and growth in albatross chicks: an interspecies chick fostering experiment. Ornis Scandinavica, 12, 207210.

K.M. Proffitt , R.A. Garrott , J.J. Rotella , D.B. Siniff J.W. Testa 2007. Exploring linkages between abiotic oceanographic processes and a top-trophic predator in an Antarctic ecosystem. Ecosystems, 10, 119126.

M. Scheffer , S. Carpenter B. De Young 2005. Cascading effects of overfishing marine systems. Trends in Ecology and Evolution, 20, 579581.

D.E. Schindler , T.E. Essington , J.F. Kitchell , C. Boggs R. Hilborn 2002. Sharks and tunas: fisheries impacts on predators with contrasting life histories. Ecological Applications, 12, 735748.

M.S.R. Smith 1965. Seasonal movements of the Weddell seal in McMurdo Sound, Antarctica. Journal of Wildlife Management, 29, 464470.

I. Stirling 1969. Ecology of the Weddell seal in McMurdo Sound, Antarctica. Ecology, 50, 573586.

L.L. Tieszen , T.W. Boutton , K.G. Tesdahl N.A. Slade 1983. Fractionation and turnover of stable carbon isotopes in animal tissues: implications for analysis of diet. Oecologia, 57, 3237.

J.W. Testa , G. Oehlert , D.G. Ainley , J.L. Bengston , D.B. Siniff , R.M. Laws D. Rounsevell 1991. Temporal variability in Antarctic marine ecosystems: periodic fluctuations in the phocid seals. Canadian Journal of Fisheries and Aquatic Sciences, 48, 631639.

J.W. Testa D.B. Siniff 1987. Population dynamics of Weddell seals (Leptonychotes weddellii) in McMurdo Sound, Antarctica. Ecological Monographs, 57, 149165.

J.W. Testa , D.B. Sinniff , M.J. Ross J.D. Winter 1985. Weddell seal-Antarctic cod interactions in McMurdo Sound, Antarctica. InSeigfried, W.R., Condy, P.R. &Laws, R.M., eds. Antarctic nutrient cycles and food webs. Heidelberg: Springer, 561565.

L. Zhao , M.A. Castellini , T.L. Mau , S.J. Trumble 2004. Trophic interactions of Antarctic seals silverfish determined by stable isotope signatures. Polar Biology, 27, 368373.

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Antarctic Science
  • ISSN: 0954-1020
  • EISSN: 1365-2079
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