Population and feeding dynamics of red mullet (Mullus barbatus) in bentic ecosystem, in the Eastern Black Sea

A total of 2930 Mullus barbatus individuals collected from the Southeastern Black Sea coast between March 2017 and April 2018 were investigated regarding, growth, reproduction, feeding habits, mortality rates and the distribution determined by depth and season. The pattern rates of sexes as 48.32% of the individuals were male and 51.67% female. It was determined that the total length ranges from 5.2 cm to 20.1 cm in males and from 5.6 cm to 23.6 cm in females. Total length-weight relationship was determined as W =0,005L3,2344.Von Bertalanffy growth parameters for all individuals were calculated as L∞=28,19 cm, K=0.16 years-1, t0 =-0,144 years. The maximum age was 5 years. The first sexual maturity was estimated as 11.63 cm in males and 11.68 cm in females. If gonadosomatic index and condition factors of the individuals were considered together, the reproduction period is determined to be continued from the beginning of spring to the end of summer. The exploitation rate (E) of population calculated as 0,70 year_1 (mean length). Exponential coefficients of natural mortality (M), total mortality (Z), and fishing mortality (F) of Mullus barbatus are estimated as 0,30 year-1, 1,061 year-1, 0,76 year-1 respectively. The exploitation rate (E) of population calculated that 0,72 year-1 (first catch length). The fact that exploitation rate is above 0.5, may reflect a high fishing pressure on this stock. It was determined that the main prey were Bivalvia group followed by Nematoda, Polycheta and Gastrapoda groups, respectively. When the seasonal distribution of the species was examined, it was determined that the species is abundant along the depth of 30-45 m depth in winter. The number of eggs spawn at once by a fish of 12.7 cm in length was minimum of 610, by a fish of 22.3 cm of maximum 11930 and the average was 2780.6 ± 227.09.