CONDITION AND CPUE OF EUROPEAN GRAYLING (Thymallus thymallus L.) POPULATION IN THE CROATIAN KUPA RIVER

Abstract

The study was carried out on the material of 98 European grayling (Thymallus thymallus L., 1758) from upper part Kupa river, in northwest Croatia. The research included angling by fly fishing tackle and collecting the data of fish species characteristics. Values of condition factor (CF) ranged from 0.615 to 2.239, but average value of this parameter is 1.094±0.27. The condition factor by dates of sampling indicated that all grayling caught before November, have had a negative condition factor. The quantity of fish present in the upper part of the Kupa river was evaluated using the catch per unit efforts (CPUE) parameter. The average value of CPUE parameter is 2.25±1.01.

Keywords

• european grayling
• thymallus
• condition factor
• croatia