Age and growth determination of the golden grey mullet, Liza aurata (Risso, 1810) from the Adriatic Sea by using scale readings and length frequency analysis
Keywords:
Golden grey mullet, age determination methods, growth, Adriatic SeaAbstract
The age and growth of golden grey mullet, Liza aurata (Risso, 1810), were determined from specimens collected in the Mirna estuary (northern Adriatic Sea) during December of 2001, 2002 and 2003. The age composition was established using scale readings and Bhattacharya’s method. Nine age classes ranging from 3.2 to 13.2 years (except 10.2 and 11.2) were defined by scale readings but only seven (age 3.2: 23.29 cm, age 4.2: 26.75 cm, age 5.2: 29.05 cm, age 6.2: 31.18 cm, age 7.2: 32.71 cm, age 8.2: 34.42 cm and age 9.2: 35.50 cm) were obtained by Bhattacharya’s method. Total length ranged between 21.7 and 40.4 cm. Mean length and weight at age data, as derived using scale readings, were used to estimate the growth parameters of the von Bertalanffy equation: L∞=40.0, K=0.214, to=-1.150; W∞=606g, K=0.162 and to=-1.962. The length-weight relationship indicated positive allometric growth (b=3.069).