FOOD COMPOSITION OF GRAYLING Thymallus thymallus L., FROM THE RIVER KRUŠNICA

Abstract

Total of 118 specimens of grayling (Thymallus thymallus L.) is caught with sport fishing techniques in the river Krušnica. The objectives of this research was to obtain data about the diet composition of these species in natural biotopes. Dominant food of grayling from the river Kru{nica were Amphipoda and Ephemeroptera, while the most abundant number belonging to the group of Diptera. Secondary diet consists of Trichoptera with Hydrop%syche sp. as dominant species, then Gastropoda with Valvata sp., Coleoptera and Formicidae. Grayling occasionally consume Isopoda, Hirudinea, Plecoptera, Oligochaeta, Heteroptera, Aranea, Lepidoptera, Hydracarina and Hymenoptera, as well as plant detritus.

Keywords

• grayling
• thymallus
• krušnica
• natural nutrition