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

摘要

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 Izmir 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 (0) 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.%Ukupno je ulovljeno 546 primjeraka lastavice balavice (Chelidonichthys lucernus L., 1758) na temelju mjesečnog sakupljanja koćom tijekom rujna 1999. i kolovoza 2000. u izmirskom zaljevu (Egejsko more). Vilična duljina tijela kod ženki kretala se od 12.7 do 34.4 cm, a mužjaka od 14.1 do 29.9 cm. Odnos spolova mužjaka i ženki iznosio je 1:0.52. Najveća starosna dob ustanovljena za ženke bila je 5, a za mužjake 3, dok je dužinsko-maseni iznosio za ženke W=0.0051*L~(3.245) i za mužjake W=0.0053~*L~(3.237). Vrijednosti dobivene von Bertalanffy-ijevom jednadžbom iznosile su L_t=49.09(1-e~(-0.186(t+1.484))) za ženke, L_t=31.44(1-e~(0.886(t+0.886))) za mužjake, te L_t=52.12(1-e~(0.163(t+0.163))) za oba spola. Vrijednost indeksa rasta (Φ) je iznosio 2.646 za sve primjerke. Gonadosomatski indeks ukazuje da se vrijeme mriješćenja odvijalo tijekom prosinca (2.268) sve do kraja ožujka (6.158). Vilična duljina tijela zrelih mužjaka iznosila je 17.7 cm, a ženki 19.0 cm.