Estimation of growth and population parameters of mullet fishes (mullidae family: Mullus barbatus pontius, Mullus surmuletus, Upeneus moluccensis) captured by demersal trawl

Growth and population parameters of the three mullet species (Mullus barbatus ponticus, Mullus surmuletus, Upeneus moluccensis) living in Turkey sea were estimated. The study was carried out between 1 September 2014 and 15 April 2015 date. Study data were obtained from commercial fishing vessels engaged in demersal trawling in the Black Sea (Samsun) and Mediterranean (Mersin) coasts. The average length values of the species were determined as 12.67±0.09 cm, 11.55±0.11 cm and 13.48 ±0.08 cm, in order. The length-weight relationship equations were calculated as W=0.0132L2.9066 for Mullus barabatus ponticus, W=0.0088L3.101 for Mullus surmuletus and W=0.0079L3.002 for Upeneus moluccensis. Growth parameters were estimated as asymptotic lengths (L∞) 25.08 cm, 27.3 cm and 23.5 cm, brody growth coefficient (K) 0.24, 0.52 and 0.61 and the age before birth (t0) of the fish -1.82, -3.65 and -1.05, respectively. Instantaneous death rates (Z), natural mortality (M) and fishery mortality rates (F) of the species were determined as 2,96; 4.57; 2.17, 0.48;0.80;0.85, 2.48; 3.52; 1.32, respectively. The operating ratio (E) was found as 0.83 for Mullus barabatus ponticus, 0.82 for Mullus surmuletus and 0.60 for Upeneus moluccensis. All the estimated parameters for the species in the study were compared with the previous studies.