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Structure and Seasonal Fluctuations of Rocky Littoral Fish Assemblages in South-Western Portugal: Implications for Otter Prey Availability

Published online by Cambridge University Press:  11 May 2009

Pedro Rui Beja
Pedro Rui Beja
Affiliation:
Laboratório Marítimo da Guia, Forte de Na Sra da Guia, 2750 Cascais, Portugal
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Extract

The fish assemblages of rocky intertidal and subtidal (<3 m depth) habitats of the south-western Portuguese coast were sampled between May 1992 and November 1993, using traps, angling and hand-netting, to investigate their structure and seasonal dynamics. The main purpose of the study was to describe the patterns of prey availability for marine-feeding otters (Lutra lutra L., Mammalia) in south-western Portugal, and to compare these with other areas in Europe. A total of 475 fish of 14 species was captured over 150 d of trapping (788 trap-days), and 1575 fish of 15 species were captured over 24 d of angling (76.3h). Hand-netting was carried out occasionally, to supplement the observations from the other methods, and only 96 fish of seven species were captured. The three methods yielded different patterns of the fish assemblage: giant gobies (Gobius cobitis Pallas, 33.7%) and rock gobies (G. paganellus L., 22.9%) were the most frequently trapped fish; corkwing wrasse (Symphodus melons (L.), 81.2%) were the usual species caught by angling; shannies (Lipophrys pholis (L.), 42.7%) and Montagu's blennies (Coryphoblennius galerita (L.), 28.1%) were the most frequently netted species. Conger eels (Conger conger (L.)), giant gobies and shannies showed an uneven distribution along the coast, occurring most frequently in schist shelves, rather than in areas of large sandstone boulders. There was a large seasonal variation, with the catches of most species peaking in winter and early spring, including the majority of those most important in the diet of otters: conger eels, shore rocklings (Gaidropsarus mediterraneus L.), rock gobies and corkwing wrasse. This was also the period when the individuals of several species were heaviest.

Type
Research Article
Information
Journal of the Marine Biological Association of the United Kingdom , Volume 75 , Issue 4 , November 1995 , pp. 833 - 847
Copyright
Copyright © Marine Biological Association of the United Kingdom 1995

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References

Almada, V.C., Barata, E.N., Goncalves, E.J. & Oliveira, R.F. De, 1990. On the breeding season of Lipophrys pholis (Pisces: Blenniidae) at Arrábida, Portugal. Journal of the Marine Biological Association of the United Kingdom, 70, 913–916.CrossRefGoogle Scholar
Almada, V.C., Gonçalves, E.J., Oliveira, R.F. De & Barata, E.N., 1992. Some features of the territories in the breeding males of the intertidal blenny Lipophrys pholis (Pisces: Blenniidae). Journal of the Marine Biological Association of the United Kingdom, 72, 187–197.CrossRefGoogle Scholar
Arruda, L.M., 1979. Specific composition and relative abundance of intertidal fish at two places on the Portuguese coast (Sesimbra & Magoito, 1977–78). Arquivos do Museu Bocage, série 2, 6, 325–342.Google Scholar
Arruda, L.M., 1990. Population structures of fish in the intertidal ranges of the Portuguese coasts. Vie et Milieu, 40, 319–323.Google Scholar
Beja, P.R., 1991. Diet of otters (Lutra lutra) in closely associated freshwater, brackish and marine habitats in south-west Portugal. Journal of Zoology, 225, 141–152.CrossRefGoogle Scholar
Cochran, W.G. & Cox, G.M., 1957. Experimental design. New York: John Wiley & Sons.Google Scholar
Diggle, P.J., 1990. Time series. A biostatistical introduction. Oxford University Press.CrossRefGoogle Scholar
Faria, C. & Almada, V.C., in press. Some aspects of the breeding ecology of Gobius cobitis Pallas and Gobius paganellus L. in the west coast of Portugal. Arquivos do Museu Bocage.Google Scholar
Gibson, R.N., 1972. The vertical distribution and feeding relationships of intertidal fish on the Atlantic coast of France. Journal of Animal Ecology, 41, 189–207.CrossRefGoogle Scholar
Gomes, J.A. & Almeida, A.J., 1979. Notes sur l'ichthyofaune du littoral rocheux Portugais. In Actas del Primer Simposio Ibérico de Estudios de Bentos Marino (ed. F.X., Niell and J., Ros), pp. 317–332. San Sebástian: Socedad Cultural INSUB.Google Scholar
Harmelin, J.-G., 1987. Structure et variabilité de l'ichtyofaune d'une zone rocheuse protegée en Méditerranée (Pare National de Port-Cros, France). Marine Ecology. Pubblicazioni della Stazione Zoologica de Napoli I, 8, 263–284.CrossRefGoogle Scholar
Heggberget, T.M., 1993. Marine-feeding otters (Lutra lutra) in Norway: seasonal variation in prey and reproductive timing. Journal of the Marine Biological Association of the United Kingdom, 73, 297–312.CrossRefGoogle Scholar
Heggberget, T.M. & Christensen, H., 1994. Reproductive timing in Eurasian otters on the coast of Norway. Ecography, 17, 339–348.CrossRefGoogle Scholar
Hillden, N.-O., 1984. Behavioural ecology of the labridfish (Teleostei: Labridae) at Tjarno on the Swedish west coast. PhD thesis, University of Stockholm.Google Scholar
Kotrschal, K. & Reynolds, W.W., 1982. Behavioral ecology of northern Adriatic reef fishes in relation to seasonal temperature regimes. Contributions in Marine Science, University of Texas, 25, 99–106.Google Scholar
Kruuk, H. & Conroy, J.W.H., 1991. Mortality of otters (Lutra lutra) in Shetland. Journal of Applied Ecology, 28, 83–94.CrossRefGoogle Scholar
Kruuk, H., Conroy, J.W.H. & Moorhouse, A., 1987. Seasonal reproduction, mortality and food of otters Lutra lutra L. in Shetland. Symposia of the Zoological Society of London, 58, 263–278.Google Scholar
Kruuk, H., Conroy, J.W.H. & Moorhouse, A., 1991. Recruitment to a population of otters (Lutra lutra) in Shetland, in relation to fish abundance. Journal of Applied Ecology, 28, 95–101.CrossRefGoogle Scholar
Kruuk, H., Glimmerveen, U. & Ouwerkerk, E.J., 1985. The effects of depth on otter foraging in the sea. Report. Institute of Terrestrial Ecology, 1984, 112–115.Google Scholar
Kruuk, H. & Moorhouse, A., 1990. Seasonal and spatial differences in food selection by otters (Lutra lutra) in Shetland. Journal of Zoology, 221, 621–637.CrossRefGoogle Scholar
Kruuk, H., Nolet, B. & French, D., 1988. Fluctuations in numbers and activity of inshore demersal fishes in Shetland. Journal of the Marine Biological Association of the United Kingdom, 68, 601–617.CrossRefGoogle Scholar
Nolet, B.A., Wansink, D.E.H. & Kruuk, H., 1993. Diving of otters (Lutra lutra) in a marine habitat: use of depths by a single-prey loader. Journal of Animal Ecology, 62, 22–32.CrossRefGoogle Scholar
Oftedal, O.T. & Gittleman, J.L. 1989. Patterns of energy output during reproduction in carnivores. In Carnivore behaviour, ecology and evolution (ed. J.L., Gittleman), pp. 355–378. London: Chapman and Hall.CrossRefGoogle Scholar
Reynolds, W.W., 1977. Temperature as a proximate factor in orientation behavior. Journal of the Fisheries Research Board of Canada, 34, 734–739.CrossRefGoogle Scholar
Sayer, M.D.J., Cameron, K.S. & Wilkinson, G., 1994. Fish species found in the rocky sublittoral during winter months as revealed by the underwater application of the anaesthetic quinal-dine. Journal of Fish Biology, 44, 351–353.CrossRefGoogle Scholar
Shardlow, T.F., 1994. Components analysis of a density-dependent catchability coefficient in a salmon hook and line fishery. Canadian Journal of Fisheries and Aquatic Sciences, 50, 513–520.CrossRefGoogle Scholar
Siegel, S. & Castellan, N.J., 1988. Nonparametric statistics for the behavioural sciences, 2nd ed.New York: McGraw-Hill International.Google Scholar
Smale, M.J. & Buxton, C.D., 1989. The subtidal gully fish community of the eastern Cape and the role of this habitat as a nursery area. South African Journal of Zoology, 24, 58–67.CrossRefGoogle Scholar
Sokal, R.R. & Rohlf, F.J., 1981. Biometry, 2nd ed.San Francisco: W.H. Freeman.Google Scholar
Stott, B., 1970. Some factors affecting the catching power of unbaited fish traps. Journal of Fish Biology, 2, 15–22.CrossRefGoogle Scholar
Ter, Braak C.J.F., 1987. CANOCO - a FORTRAN program for canonical community ordination by [partial] [detrended] [canonical] correspondence analysis and redundancy analysis (version 2–1). Wageningen: TNO Institute of Applied Computer Science.Google Scholar
Vanicsek, L. & Ludvig, É., 1992. The method of running-averages in the study of breeding parameters: an example of the blackbirds (Turdus merula). Ornis Hungarica, 2, 1–10.Google Scholar
Watt, J., 1991. Prey selection by coastal otters ( Lutra lutra L.). PhD thesis, University of Aberdeen.Google Scholar