Ryszard Bartel, Rafał Pender, Adam Tański, Łukasz Potkański, Emilian Pilch
ABSTRACT. After a break of eighteen years, catches of vimba bream were begun again in the Rega River in 2002. In the 2004-2007 period, 521953 individuals of vimba bream fry were released into the Rega River. Vimba bream spawners were caught in the Rega River in 2008 between the towns of Gryfino and Trzebiatowo. A total of 231 fish were caught, of which 121 were males and 110 were females. Among the females, 16 were not spent, while 96 were spent to varying degrees. All of the females were subjected to hormonal stimulation. Following artificial reproduction, the spawners were released at the site where they had been caught. The mean length of females was 333.9 mm, at a length range of 250 to 410 mm. The dominant length classes were 321-340 and 341-360 mm, which corresponded to 35.7 and 21.4% of the number of females caught, respectively. The mean length of the males was 291.1 mm, at a range of 175 to 340 mm. The dominants were from the two longest length classes, which together comprised 51% of the number of males caught. The number of vimba bream caught per fishing day ranged from zero to 35 individuals. The number of spawners caught increased with increasing water temperature.
Keywords: Rega River, vimba bream, spawner catches
Przyjęto po recenzji 27.11.2008 r.