SEXUAL-MATURATION, AGE AND GROWTH OF STRIPED SEA BREAM, LITHOGNATHUS-MORMYRUS L, ON THE EASTERN COAST OF THE ADRIATIC SEA

Striped sea bream, Lithognathus mormyrus L., are hermaphoroditic prota ndrous fish. Sex ratios are given for length and age classes, indicati ngthe males change sex mainly at lengths between 25.0 and 32.5 cm, in age classes 4 to 7, with more than 30 % of the population changing sex in age class 6 to 7. Males were also observed up to a length of 34.5 cm. Length-weight relationship showed no significant difference from i sometric growth in winter (b=3.05) and a negative allometric growth in summer (b=2.69). The age composition was established using the Bhatta charya method and additional observations of annual rings on scales. S ix age classes were obtained from Kastela Bay (age 3:21.7 cm, age 4:26 .5 cm, age 5:28.4 cm, age 6:30.3 cm, age 7:31.6 cm, age 8:33.4 cm) and from Mirna Bay (age 2.5:19.4 cm, age 3.5:24.1 cm, age 4.5:26.9, age 5 .5:29.4 cm, age 6.5:31.3 cm, age 7.5:32.8 cm). Von Bertalanffy's growt h equation was fitted to these mean length-at-age data resulting In pa rameter values of L(infinity)=36.2 cm, K=0.297, t(0)=-0.08 for Kastela Bay and L(infinity)=37.3 cm, K=0.262, t(0)=-0.39 for Mirna Bay.