Age and growth of albacore (Thunnus alalunga Bonnaterre, 1788) from the eastern Mediterranean

Authors: FİRDES SAADET KARAKULAK, ELİF ÖZGÜR, MEHMET GÖKOĞLU, İBRAHİM TAMER EMECAN, ALPARSLAN BAŞKAYA

Abstract: This study was designed to characterize the growth parameters of the albacore, Thunnus alalunga, in the eastern Mediterranean. A total of 819 albacore specimens were collected from gillnet boats operating in Antalya Bay (in the Levantine Sea) between May and July from 2006 to 2008. Individuals were all between 55 and 101 cm in fork length (FL). The fork length was directly proportional to weight, with a relationship of W = 0.00042FL^{2.246} for females, W = 0.00022FL^{2.396} for males, and W = 0.00016FL^{2.467} for males and females combined. Negatively allometric growth was observed in all individuals. Age and growth were estimated by assessing seasonal bands formed on the first dorsal spines of 744 specimens. Albacore samples were estimated to be between 1 and 9 years old. Von Bertalanffy growth parameters were estimated for all individuals and for males and females independently. There were significant differences between growth patterns in males and females. The von Bertalanffy growth parameters for both sexes and all years combined were L_{\infinity} = 93.198 cm, W_{\infinity} = 11.552, k= 0.295 year^{-1} and t_{o} = -1.213 years.

Keywords: Albacore, Thunnus alalunga, age, growth, spine, eastern Mediterranean Sea

Full Text: PDF