Fecundity and egg size in sea trout (Salmo trutta m. trutta L.) in pond conditions

Abstract

uring a five-year period, the fecundity and egg size of individual Vistula sea trout marked with PIT tags were studied. The dependencies between fish length, age and the number of times the fish had spawned and its fecundity and egg size were analyzed. Both fecundity and egg size increased as fish length increased. However, after taking into consideration fish growth, fecundity decreased slightly with age while egg size increased. These two traits were mutually inversely correlated. After taking into consideration differences in length, fish that were spawning for the first time were less fecund than their peers at a similar egg size.

CORRESPONDING AUTHOR:

Dr hab. Piotr Dębowski, Instytut Rybactwa Śródlądowego, Zakład Ryb Wędrownych, ul. Reduta Żbik 5, 80-761 Gdańsk, Tel./Fax: +48 (58) 305 70 11; e-mail: pdebow@infish.com.pl.