Age and growth of the Black Sea turbot, Psetta maxima (Linneaus, 1758) (Pisces : Scophthalmidae), estimated by reading otoliths and by back-calculation

Abstract

Age and growth of the Black Sea turbot, Psetta maxima, were determined from a total of 1445 individuals collected along the eastern Black Sea coast between 1990 and 1996. Age was estimated by interpreting growth rings in whole and broken sagittal otoliths. The former method underestimated the age over 5 years, and a maximum age of 11 years was observed by the latter. Marginal increment analysis clearly showed that a single annulus is formed in early summer each year. Growth in length differed between sexes, and females attained a larger size than males at the same age. No significant difference was found between the mean observed total length (TL), the back-calculated TL derived from radius measurements and the TL estimated from otolith size-fish size relationship. The von Bertalanffy growth parameters estimated by the length-at-age data were: L-infinity = 96.24 cm; K = 0.119 year(-1); t(0) = -0.01 year for the entire population.