Popis: |
Length composition of anchovy (Engraulis encrasicolus, L.) and sprat (Sprattus sprattus L.), important small pelagic species of Black Sea, were determined in this study. Growth parameters and mortality rates for anchovy and sprat, using length composition data of fishes, were estimated. A total of 150 tons anchovy and 75 tons sprat (225 tons fish) were caught end of the 13 midwater trawl tows in the study. Length of 1516 numbers anchovy and 4214 numbers sprat were measured in the study. Maximum, minimum and average length of species were established 15.2 cm, 5.2 cm, 11.28±0.04 cm; 12.8 cm, 5.7 cm, 8.5±0.01 cm respectively. Growth and population parameters of anchovy and sprat were calculated; asymptotic length (L∞) 17.01 cm, 13.38 cm, Brody growth coefficient (K) 0.28, 0.23; instantaneous rate of mortality (Z) 2.73 year-1, 2.88 year-1; rate of natural mortality (M) 0.41 year-1, 0.52 year-1, rate of fishing mortality (F) 2.18 year-1, 1.51 year-1, exploitation rate (E) 0.80 year-1, 0.82 year-1 respectively. Growth and population parameters, calculated by the length composition for species, were compared with other studies. |