Age, Growth and Reproductive Biology of the Common Two-Banded Seabream (Diplodus vulgaris Geoffroy Saint-Hilaire, 1817) from the Northern Aegean Sea, Turkey

Abstract

The present study aims to describe population dynamics (age, growth, mortality and fecundity) of common two-banded seabream. Sampled individuals were obtained monthly between November 2017 and October 2018 directly from commercial fisherman in the Northern Aegean Sea. Ages were estimated from 327 otolith readings; the minimum and maximum ages observed were 1 and 8 years, respectively, corresponding to 13 and 29 cm total length (TL). The length-weight relationship was W = 0.0156*L2.97 (R2 = 0.92) for the whole population and isometric growth was detected. The growth parameters of Von Bertalanffy fitted to back-calculated size for age data were: L∞ = 30.69 cm, K = 0.20 and t0 = −2.64 per year. The instantaneous rates of total mortality (Z) and natural mortality (M) were 0.86 and 0.47 per year, respectively. Rates of fishing mortality F and exploitation E were 0.39 and 0.35 per year, respectively. The spawning season extended from September to March and peaked in December. Total lengths at 50% maturity were 18.32 cm for males and 20.37 cm for females. Mean absolute fecundity (F) was 73,154 ± 10,271 oocytes, ranging from 10,727 to 316,730.