Some biological parameters of horse mackerel Trachurus trachurus (L., 1758) caught from the Dardanelles

Growth parameters and gonadosomatic index (GSI) (%) of 459 horse mackerel Trachurus trachurus (L. 1758) were studied in Dardanelles between September 2001 and August 2002. The age composition of the sampled population varied between 0 and 3, where the 0-age group contained the highest number of fish (59.0%). The population was composed of 57% females and 43% males, respectively. The total length varied from 8.80 to 25.90 cm and the body weight varied from 8.50 to 171.72 g. The Von Bertalanffy equation was estimated as Lt = 30.34 (1 - e (-0.255) ((t + 2.481))) for both sexes combined. Maximum monthly mean of the GSI for males (3.77%) and females (3.91%) were observed in April 2003.