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Ontogenetic changes in the feeding habits and dietary overlap between three abundant rajid species on the Falkland Islands' shelf

Published online by Cambridge University Press:  19 September 2003

P. Brickle*
Affiliation:
Falkland Islands Government Fisheries Department, PO Box 598, Stanley, Falkland Islands
V. Laptikhovsky
Affiliation:
Falkland Islands Government Fisheries Department, PO Box 598, Stanley, Falkland Islands
J. Pompert
Affiliation:
Falkland Islands Government Fisheries Department, PO Box 598, Stanley, Falkland Islands
A. Bishop
Affiliation:
Falkland Islands Government Fisheries Department, PO Box 598, Stanley, Falkland Islands
*
Corresponding author, e-mail: pbrickle@¢sheries.gov.fk

Abstract

The ontogenetic changes in the diet and dietary overlap of three commercially important rajid species inhabiting the slope and shelf waters of the Falkland Islands were investigated. The white dotted skate (Bathyraja albomaculata) was a specialized amphipod and polychaete feeder. The broad nose skate (B. brachyurops) had a diverse diet, consuming a wide variety of crustaceans and fish. The grey tail skate (B. griseocauda) also had a broad diet but consumed a high proportion of amphipods and isopods (e.g. Serolis spp.). Larger individuals of the latter species were more piscivorous and consumed more squid. The diets of all three species showed a marked variation with ontogeny. Dietary overlap was greatest for smaller animals (<30 cm disk width), after which each species became more specialized in their diets. Smaller animals also showed some differences in depth of distribution, which may be an adaptation to reduce inter-specific competition.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 2003

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References

Ajayi, T.O., 1982. Food and feeding habits of Raja species (Batoidei) in Camarthen Bay, Bristol Channel. Journal of the Marine Biological Association of the United Kingdom, 62, 215–223.Google Scholar
Alonso, K.M., Crespso, E.A., Garcia, N.A., Pedraza, S.N., Mariotti, B., Vera, B.B. & Mora, N.J., 2001. Food habits of Dipturus chilensis (Pisces: Rajidae) off Patagonia, Argentina. ICES Journal of Marine Science, 58, 288–297.Google Scholar
Arkhipkin, A., Brickle, P., Laptikhovsky, V., Butcher, L., Jones, E., Potter, M. & Poulding, D., 2001. Variations in the diet of the red cod with size and season around the Falkland Islands (south-west Atlantic). Journal of the Marine Biological Association of the United Kingdom, 81, 1035–1040.CrossRefGoogle Scholar
Calliet, G.M., Love, M.S. & Ebeling, A.W., 1986. Fishes: afield and laboratory manual on their structure, Identification, and natural history. Belmont, California: Wadsworth Publishing Company.Google Scholar
Cortes, E., 1997. A critical review of the methods of studying fish feeding based on analysis of stomach contents: application to elasmobranch fishes. Canadian Journal of Fisheries and Aquatic Sciences, 54, 726–738.CrossRefGoogle Scholar
Ellis, J.R., Pawson, M.G. & Shakley, S.E., 1996. The comparative feeding ecology of six species of shark and four species of ray (Elasmobranchii) in the north-east Atlantic. Journal of the Marine Biological Association of the United Kingdom, 76, 89–106.Google Scholar
Falkland Islands Government, 2001. Fisheries department fisheries statistics, vol. 5, 2000, 68 pp. Stanley: FIG Fisheries Department.Google Scholar
Gallagher, M.J., 2000. Fisheries biology of commercial ray species from two geographically distinct regions. PhD thesis, University of Dublin, Trinity College, Ireland.Google Scholar
Holden, M.J. & Tucker, R.N., 1974. Food of Raja clavata Linnaeus 1758, Raja montiagui Fowler 1910, Raja naevus Mu«ller and Henle 1841 and Raja brachyura Lafont 1873 in British waters. Journal du Conseil, 35, 189–193.Google Scholar
Krebs, C.J., 1989. Ecological methodology. New York: Harper Collins.Google Scholar
Laptikovsky, W. & Arkhipkin, A.I., 2003. An impact of season squid migrations and fishing on| the feeding spectra of sub-antarctic notothenioids Patagonotothen ramsayi and Cottoperca gobio around the Falkland Islands. Journal of Applied Ichthyology, 19, 35–39.Google Scholar
Laptikovsky, W., Arkhipkin, A.I. & Henderson, A.C., 2001. Feeding habits and dietary overlap in spiny dogfish Squalus acanthias (Squalidae) and narrow mouth catshark Schroederichthys bivis (Scyliorinidae). Journal of the Marine Biological Association of the United Kingdom, 81, 1015–1018.Google Scholar
Lucifora, L.O., Valero, J.L., Bremec, C.S. & Lasta, M.L., 2000. Feeding habits and prey selection by the skate Dipturus chilensis (Elasmobranchii: Rajidae) from the south-western Atlantic. Journal of the Marine Biological Association of the United Kingdom, 80, 953–954.Google Scholar
McEachran, J.D., Boesch, D.F. & Musick, J.A., 1976. Food divi-sion within two sympatric species-pairs of skates (Pisces: Rajidae). Marine Biology, 35, 301-317.Google Scholar
Macpherson, E., 1981. Resource partitioning in a Mediterranean demersal fish community. Marine Ecology Progress Series, 4, 183–93.CrossRefGoogle Scholar
Smale, M.J. & Cowley, P.D., 1992. The feeding ecology of skates (Batoidea: Rajidae) off the Cape south coast, South Africa. South Afric an Journal of Marine Science, 12, 823–834.Google Scholar