Predation on young Paracentrotus lividus settlers: implications for Mediterranean rocky infralittoral stability

Predation of young sea urchins settlers are often invoked as a key process in the control of sea urchins populations and therefore in the structure and stability of rocky infralittoral communities. In this study a number of decapod species were detected as predators of young settlers of the sea urchin Paracentrotus lividus and their predation rates estimated by laboratory experiments. Abundance of these predators also resulted significantly lower in barren than in macro algae forests, suggesting that lack of predation of juvenile sea urchins facilitates the stability of Mediterranean barren systems.