PROGETTO URCHIN: VALUTAZIONE QUANTITATIVA DELLA POPOLAZIONE DI PARACENTROTUS LIVIDUS (RICCIO DI MARE) NELL’AREA MARINA PROTETTA PARCO SOMMERSO DI GAIOLA

URCHIN PROJECT: QUANTITATIVE ASSESSMENT OF THE POPULATION OF PARACENTROTUS LIVIDUS (SEA URCHIN) IN THE MARINE PROTECTED AREA GAIOLA UNDERWATER PARK

Abstract

The URCHIN project (“Underwater Research Coralligenous Habitats In Naples”) investigates the conservation status of the Natura 2000 SAC IT8030041 “Fondali Marini di Gaiola e Nisida” by monitoring coralligenous habitats and sea urchins. This paper focuses on the second objective, analysing the abundance, distribution, and demographic structure of the commercial species Paracentrotus lividus. Surveys conducted within the Gaiola Marine Protected Area (MPA) and surrounding zones highlight a strong reserve effect: P. lividus shows higher densities and larger size classes in the fully protected Zone A. Data on associated fish communities indicate that inside the MPA, natural predation regulates populations, while outside the MPA, illegal fishing is the dominant pressure. These findings emphasise the effectiveness of protection measures in enhancing sea urchin populations and preserving ecological balance within the MPA.