Variazioni temporali della struttura di taglia in popolazioni sfruttate di Haliotis tuberculata (Mollusca Gastropoda) nel Golfo di Sferracavallo (PA)

This study aims at evaluating the differences in size structure of population of H. tuberculata in the Gulf of Sferracavallo (northern Sicily) which experienced the co-occurrence of high exploitation and decrease of eutrophic conditions during the eighties and early nineties. Comparison of size structure showed significant differences between length frequency distributions of 1970-75s and 2002-2005, being the latter formed by smaller size green ormer.