Preliminary communication
THE GROWTH OF GRAYLING (THYMALLUS THYMALLUS L.) IN THE KUPA RIVER
2005, 63 (2) p. 39-46
Nikica Šprem, Tea Tomljanović, Marina Piria, Tomislav Treer, Roman Safner, Ivica Aničić
Abstract
The growth of grayling (Thymallus thymallus L.) was analyzed on specimen of 98 fish, caught whit sport-fishing equipment in upper part of the Kupa river, northwest Croatia. The research was conducted in 2002 fishing season, monthly from May to November. The total length of caught grayling ranged from 17.0 to 41.0 cm, and weight from 40 to 700 g. The growth in total length of this population could be expressed by the following von Bertalanffy expression: Lt= 69.77(1 – e-0.1214(t-1.25)). The overall growth performance (Φ') has minimum variance, and average value of our population is Φ'=6.38±0.14. Weight express a negative allometric growth (b=2.643).