Age, growth and reproduction of tub gurnard Chelidonichthys lucernus Linnaeus, 1758 (Osteichthtyes:Triglidae) from İzmir Bay, Aegean Sea, Eastern Mediterranean

Abstract

         A total of 546 tub gurnard (Chelidonichthys lucernus L., 1758) were caught monthly by trawl surveys carried out between September 1999 and August 2000 in İzmir Bay (Aegean Sea). Fork lengths of females ranged from 12.7 to 34.4 cm, and of males from 14.1 to 29.9 cm. The female: male ratio was 1:0.52. The maximum age observed was 5 for females and 3 for males and the length-weight relationships were estimated as W=0.0051*L^3.245 and W=0.0053*L^3.237, respectively; the von Bertalanffy growth equations were L_t=49.09(1-e^{-0.186(t+1.484)}); L_t=31.44(1-e^{-0.886(t+0.886)}) and L_t=52.12(1-e^{-0.163(t+1.609)}) for females, males and both sexes, respectively. The growth performance index value (Φ) was computed as 2.646 for all specimens. The gonadosomatic index (GSI) values indicated that spawning occurred from late December (2.268) to the end of March (6.158). Males matured at a fork length of 17.7 cm, while females matured at 19.0 cm.