The investigation some biological characteristics marbled spinefoot (Siganus rivulatus (Forsskal 1775)) living in Iskenderun Bay

The aim of this study is determine some biological characteristics of Siganus rivulatus Bleeker. 1849 in Iskenderun Bay. A total of 531 individuals were examined by sampling monthly February 2014–Jun 2015 in the years. The length, weight, age. weight-age, length-weight, relationships condition factor and gonadosomatic index values of Siganus rivulatus were determined. The examined sample includes 166 (31.19%) female and 365 (68.49%) male specimens. The total length range for females and males was 8.5-29.5cm and 8.5-26.9 cm. respectively; and the weight range for females and males was 17.66-284.90 g and 8.37-248.25 g respectively. The length-weight relationships computed for female and male specimens was respectively as; W=0.013×L2.982 and W=0.015xL2.934. The minimum and maximum ages determined based on otholit readings for females and males ranged from 0 to 10. The growth of Siganus rivulatus was determined as izometric allometric. The computed von Bertalanffy growth parameters were estiamted as year for females. L∞ = 48.96cm. K= 0.054 year -1. t 0 = - 3.495. L∞ =45.534. K=0.059 year-1 t0=-3.646 year for males and for L∞ =47.24. K=0.054 year-1 t0 = -3.615 all population. The mean condition factor of females. males and all population were found as. 1.54±0.09 and 1.48±0.501 and 1,51±0,300 respectively. The monthly GSI values are showed spawns of Siganus rivulatus between April-May-June.