Diet shifts and food selection of perch Perca fluviatilis and roach Rutilus rutilus in humic lakes of varying water colour
Abstract:The field data from four humic lakes suggested that water colour may have both direct and indirect effects on inter- and intra-specific interactions of perch Perca fluviatilis and roach Rutilus rutilus. The results agree with suggestions that, compared with R. rutilus, P. fluviatilis may be an inferior forager on zooplankton in highly coloured water. As an indirect effect, water colour decreases the coverage of macrophytes and limits suitable littoral habitats, benefiting R. rutilus over P. fluviatilis. Perca fluviatilis benefiting from complex habitats does not have the advantage in macrophyte-poor highly coloured water.
Document Type: Regular Paper
Affiliations: 1: Department of Biological and Environmental Sciences/Aquatic Sciences, P. O. Box 65, FIN-00014 University of Helsinki, Finland 2: Finnish Game and Fisheries Research Institute, Evo Fisheries Research Station, Rahtijärventie 291, FIN-16970 Evo, Finland
Publication date: July 1, 2010