SEASONAL OCCURRENCE, ABUNDANCE AND SIZE DISTRIBUTION OF GRAY MULLET FRY (PISCES, MUGILIDAE) IN THE PORTO-LAGOS LAGOON AND LAKE VISTONIS (AEGEAN SEA, GREECE)

The seasonal occurrence, relative abundance and recruitment rate of mu llet fry in a coastal lagoon of Northern Greece has been studied. Samp les were taken monthly from April 1989 to August 1990 using a bag-sein e net. The following species of mullet were found: the common gray mul let (Mugil cephalus), the thick-lipped mullet (Chelon labrosus), the t hin-lipped mullet (Liza ramada), the golden mullet (Liza aurata) and t he leaping mullet (Liza saliens). The size distribution of each specie s was examined. Each species makes its first appearance in the ecosyst em during different months of the year although there are periods duri ng which the simultaneous presence of some species is observed. L. aur ata occurred first (beginning of the year), followed by L. ramada and later on in May by C. labrosus. L. saliens occurred in July and finall y M. cephalus in October. The highest abundance and recruitment rate w as observed for C. labrosus. In addition the spawning period of each s pecies was determined by taking into account the first appearance of t he fry.