Aspects of the early life history of European hake from the central Adriatic

During early development, the left and right sagittae of European hake Merluccius merluccius showed dimorphism in both size and shape due to the different number and size of accessory primordia. Juvenile hake reached the total length (LT) of 15 cm in c. 1 year, with monthly growth rates ranging from 1·6 cm month-1 in the third month of life to 1·1 cm month-1 towards the end of the first year. Back-calculated hatch-date distribution indicated continuous spawning with a peak in summer and a second, less evident, peak in February–March. The presence of early demersal juveniles (16–30 mm LT, c. 40 days old) very close to the Pomo pit area (Central Adriatic Sea) at c. 140 m depths indicates that the change from the pelagic to the demersal phase takes place at c. 40 days close to the area of concentration of juveniles. The daily-increment hypothesis was validated indirectly.