Age, Growth, Mortality and Reproduction Biology of the Black Seabream, Spondyliosoma cantharus in North Aegean Sea, Turkey, Mediterranean Basin

In the present study, the population parameters (length-length and length-weight relationships, age, growth, mortality) and reproductive biology (sex ratio, GSI, condition, length at first maturity, spawning period, fecundity) of black seabream (Spondyliosoma cantharus Linnaeus, 1758) were investigated. The length-length relationship and length-weight relationship were calculated as FL=0.911TL-0.0433 and W=0.0123TL(3.0614) (R-2=0.97), respectively. Parameters of the von Bertalanffy growth equation were: L-infinity=33.21 cm, K=0.21 per year, t(0) = -1.84 year and age varied between 0 and 8 years. The instantaneous rates of total mortality (Z) and natural mortality (M) were 0.64 and 0.47 per year, respectively. Rates for fishing mortality (F) and exploitation (E) were 0.17 and 0.27 per year, respectively. The spawning season extended from February to May and peaked in March and April. The female/male ratio was found to be 3.49/1 and sex inversion from female to male occurred after the 24 cm TL length group. Total lengths at 50% maturity were 22.25 cm for males and 20.59 cm for females. The mean absolute fecundity (F) was 109,457 +/- 8,011 oocytes, ranging from 59,666 to 182,589.