Macrobenthic crustaceans in the diet of demersal fish in the Bay of Biscay in relation to abundance in the environment.
In this study, the importance of the main macrobenthic crustaceans in the Bay of Biscay in the diet of 18species of demersal predatory fish was investigated by comparing stomach content data from the fishwith the results of sampling the bottom with a beam trawl. The Ivlev index was employed to evalu...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2003 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/326960 |
| Acceso en línea: | http://hdl.handle.net/10261/326960 |
| Access Level: | acceso abierto |
| Palabra clave: | Centro Oceanográfico de Santander Pesquerías |
| Sumario: | In this study, the importance of the main macrobenthic crustaceans in the Bay of Biscay in the diet of 18species of demersal predatory fish was investigated by comparing stomach content data from the fishwith the results of sampling the bottom with a beam trawl. The Ivlev index was employed to evaluatethe degree to which the crustaceans were selected in favour of other prey. Stomach content data wereweighted to the abundance of the predators in the environment in accordance with the abundanceindices obtained in the area with a bottom trawl survey, when all the data were collected. Selection ofthe crustaceans as a group varied, depending on whether biomass/volume or number was being studied,with the former value negative and the latter positive, due to the importance of the fish biomass as preyfor the predators studied. The highest mean value of the Ivlev index was obtained for the benthic shrimpProcessaspp. Other prey species with a high index werePandalina brevirostrisand the Crangonidae,and to a lesser extent Portunidae,Scyllarus arctus, Alpheus glaber, Lophogaster typicusand theAmphipoda.Processaspp. andGalatheaspp. occurred in 15 of the 18 fish species analysed. Other morearmed or protected species were negatively selected and were less important as prey, e.g.Nephropsnorvegicus, Dichelopandalus bonnieri, Plesionika heterocarpusand the Paguridae. The predatorsstudied were also classified according to trophic spectrum and the importance of macrobenthiccrustaceans in their diet.Scyliorhinus canicula, Raja clavataandLepidorhombus bosciishowed thehighest mean Ivlev index and diet diversity, while the lowest was forPagellus acarneandChelidonichthys obscurus. |
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