Portofino, a famous Italian resort town with a maritime history dating back to the Roman Empire, is a picturesque seaside community with timeless appeal and quaint charm. In 1999, a small area (approximately 3.5 square kilometers) of these stunning, temperate waters was set aside as the Portofino Marine Protected Area. The Italian government hoped to preserve the extraordinary biodiversity that attracts divers from all over the Mediterranean as well as to promote the sustainable use of the local marine life. The MPA aims to strike a difficult balance with local economies that depend almost exclusively on elite tourism and the burgeoning development and use of the Ligurian Sea by recreational fishers.
In the fall of 2004 and 2005, a team of Italian scientists set out to see how well three popular target fish species, collectively known as sea breams, were faring within three different zones of the MPA. Using SCUBA surveys, scientists counted the size and number of fish and looked at movement between the different MPA zones as well as from the MPA into nearby waters.
Overall, the response of the sea breams to MPA protection was positive, enhanced by the added benefit that spearfishing is prohibited in all three zones of the MPA. Fishes were much larger inside the MPA, and the largest fishes were found inside the central, completely protected zone. This is good news, since larger, older fish (referred to by scientists as “Big Old Fat Fertile Females”) are known to produce orders of magnitude more eggs than younger females. The presence of these large fish inside an area completely protected from fishing will help the sea breams within the MPA continue to recover.
Scientists were also seeking evidence of “spillover”, which occurs when the numbers of fish increase inside an MPA to such an extent that some adult fish move (or spillover) into nearby areas that are open to fishing. Scientists saw a gradual tapering of sea bream abundance, which was highest inside the completely protected zone, with increasing distance from the MPA border. This suggests that as seabreams, and possibly other species, recover inside the protected waters of the MPA, local artisanal and sportfishers will reap the benefits. Both the divers who enjoy the stunning underwater landscapes within the MPA and the local and tourist fishers who rely on the adjacent waters have benefited in the first 16 years of the Portofino MPA, and should continue to do so for decades to come.
To read more: LaMesa, G., A. Molinari, S. Bava, M.G. Finoia, R. Cattaneo-Vietti, L. Tunesi. 2011. Gradients of abundance of sea breams across the boundaries of a Mediterranean marine protected area. Fisheries Research 111:24-30.