Food selection of Coregonus lavaretus in a brackish water ecosystem

• Published in: Journal of fish biology 2011-02, Vol.78 (2), p.540-551
• Main Authors: Verliin, A., Kotta, J., Orav-Kotta, H., Saks, L., Vetemaa, M.
• Format: Article
• Language: English
• Subjects: Animals; Baltic Sea; Brackish; Coregonus lavaretus; Crustacea; Ecosystem; feeding selectivity; Finland; Food Preferences; Gammarus; Idotea balthica; Invertebrates; macroinvertebrates; Marine; Multivariate Analysis; Mytilus trossulus; Predatory Behavior; prey diversity; Salmonidae - physiology; whitefish
• ISSN: 0022-1112; 1095-8649
• DOI: 10.1111/j.1095-8649.2010.02870.x

This study examined how variability in the abundance and biomass structure of benthic invertebrates affected the feeding choice of the whitefish Coregonus lavaretus on a hard bottom habitat of the brackish Baltic Sea. In general, crustaceans such as Idotea balthica and Gammarus spp. were preferred over molluscs. Although being the most numerous taxon in the invertebrate samples, Mytilus trossulus was the lowest ranking in C. lavaretus food preference. The availability of benthic invertebrate prey set the dietary range of fish but the selectivity largely described fish feeding within this range. There was no clear link between fish predation and the dominance structure of benthic invertebrate communities, suggesting that species composition, abundance and biomass of invertebrate species had no impact on the feeding selectivity of the fish. Thus, while fish predation may not affect the dominant species within a benthic community, due to strong selectivity fish may impose strong pressure on some rarer but highly preferred invertebrate prey species.