Age, growth and reproduction of the rough ray, Raja radula (Delaroche, 1809) in Saros Bay (North Aegean Sea)
Cahide Çiğdem Yığın, Ali Işmen
Marine Science and Technology Faculty, Çanakkale Onsekiz Mart University, Terzioğlu Campus, Çanakkale, TURKEY
In this study age, growth and reproduction of rough ray (Raja radula) were investigated using 261 specimens from Saros Bay (North Aegean Sea) sampled between February 2005 and September 2008. Females made up 56.3% and males 43.7% of the total individuals studied. The total length of females and males ranged between 17 and 61 cm (Disc width; 11.1-39.8 cm), and between 19 and 54 cm (Disc width; 12.5-34.2 cm), respectively. The total length (TL)-weight (W) and disc width (DW)-weight relationships were described by the equations W=0.0018*TL3.35 and W=0.0081*DW3.32, respectively. Age data derived from vertebrae readings were used to estimate the growth parameters of von Bertalanffy equation: L∞=74.70 cm, K=0.20y-1, t0=-0.22y for males, and L∞=82.94 cm, K=0.16y-1, t0=-0.59y for females. The maximum age was 6 for males and 8 for females. Total length at first maturity of males and females was 40 and 46 cm, respectively.
Keywords: Raja radula, age, growth, reproduction, Saros Bay