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Timing and habitat preferences for settlement of juvenile fishes were investigated at the Marine Protected Area (MPA) of Torre Guaceto (SE Adriatic Sea) from April 2005 to March 2006. Data were obtained by visual census (on a fortnightly basis) in 10 habitat types identified within the depth range 0–6 m. A total of 22 taxa of juvenile fish was recorded: juveniles of 14 taxa were analysed for settlement timing and habitat preferences, whereas the other 8 taxa were only occasionally observed. Diplodus vulgaris and Sarpa salpa showed two settlement peaks, while the other 12 species displayed a single annual peak. Most species (10 out of 14) settled between late spring and early autumn. Juvenile labrids and Oblada melanura were mostly associated with exposed shallow rocks, while Diplodus sargus, D. vulgaris, D. puntazzo and S. salpa chiefly settled in shallow sheltered coves. Juveniles of Chromis chromis were found in sublittoral rocks and Posidonia oceanica beds. Spondilyosoma cantharus, Diplodus an...

In this study we investigated the potential of a fishing protocol adopted within the buffer zone of the Marine Protected Area of Torre Guaceto (SE Italy, Adriatic Sea) on fishing yields. The protocol, agreed with local fishermen and the MPA authority, aimed at regulating the fishing pressure within the MPA in the perspective to balance conservation and socio-economic needs. Fishing was completely banned in the entire MPA from 2001 to 2005. In 2005 fishing resumed within the buffer zone surrounding no-take zones. From 2005 to 2008 we monitored artisanal professional fishing (strictly exerted by trammel nets) within the buffer MPA, and compared CPUE (kg km −1 of net) with those obtained outside the MPA (where fishing grounds are fully open to professional and recreational fishing). Catches were higher inside than outside the MPA. Overall assemblage structures (evaluated on wet weight data) were significantly different from inside to outside the MPA, with the two most important commercial species, i.e. Mullus surmuletus and Scorpaena scrofa , accounting for ∼40% of the catch inside the MPA and ∼20% outside. In 2005, average CPUE within the MPA was about five-fold (∼50 kg km −1 of net) the mean value obtained outside. Such value then declined and tended to stabilize around 25 kg km −1 of net in 2007 and 2008. Average CPUE outside the MPA, instead, was ∼10 kg km −1 of net and remained quite stable across years. This study shows that the use of fishing co-management protocols within MPAs that properly involve local fishermen in the decision process is a promising approach to balance fishermen's and conservation needs.

Fish assemblages were assessed by visual census in sublittoral rocky reefs at the Tavolara-Punta Coda Cavallo Marine Protected Area (TMPA; Mediterranean Sea) and compared among locations characterised by different protection levels: no-take/no-access zones, two types of partial protected areas (PPAs, where professional and recreational fishing are regulated in a different way) and locations outside the TMPA. Fish assemblage structures evaluated on abundance data did not differ among different protection levels, while no-take/no-access zones clearly differed from the rest when data were expressed as biomass. Biomass of many target species was higher in no-take/no-access zones mostly due to greater fish size rather than density. For some fish (e.g. the dusky grouper Epinephelus marginatus), however, both greater density and larger size contributed to the greater biomass in no-take/no-access zones. No differences were found between the two types of PPAs, and between PPAs and the locations outside the TMPA, in terms of assemblage structures, and in density, size and biomass of target species. These results suggest the need to 1) improve management in PPAs or re-think of their role, and 2) quantitatively assess pressure of both professional and recreational fishing operating within and adjacent to MPAs, in order to allow MPAs to set up proper regulations (e.g. limiting professional or recreational fishermen, number and type of gears), and 2) achieve the best balance between ecological targets and reduction of conflicts among different categories of marine resource users.

Conservation of the Mediterranean marine ecosystems is particularly challenging; high biodiversity is combined with high human population densities and a long history of resource exploitation. Residents and users of coastal areas often perceive marine conservation and manage- ment as limiting factors to economic development. Under these conditions, the creation of compre- hensive systems of marine protected areas (MPAs) can be problematic. We selected a stretch of coast in southern Italy as a representative example of a Mediterranean coastline and nearshore marine ecosystems, featuring a complex matrix of vulnerable habitats in a landscape fragmented by multiple human activities and associated stressors. Through the use of site-selection algorithms, we investi- gated how human activities constrain MPA planning. Rather than assuming that patches of the same habitat found at different locations are interchangeable, we considered the scenario of a heteroge- neous landscape of human impacts creating high variability in habitat quality. Despite widespread human influence, identification of portions of habitats to be protected from direct human disturbance as core no-take areas is still possible using the inclusion of 10 and 30% of low and high priority habi- tat, respectively, in reserves as a conservation target. Implementation of MPAs with a limited protec- tion scheme that also include several small no-take areas could represent a feasible strategy for the conservation of Mediterranean coastal marine habitats. Moreover, MPAs could be combined with coastal zoning of activities as a means of further controlling effects over broader areas and allowing for recovery of degraded areas. Site-selection algorithms are invaluable tools for conservation plan- ning. However, careful consideration of the potential constraints imposed by local human activities and future research aimed at filling existing gaps in understanding the ecology are crucial for mak- ing this approach useful in marine conservation planning.

Marine protected areas (MPAs) have become popular tools worldwide for ecosystem conservation and fishery management. Fish assemblages can benefit from protection provided by MPAs, especially those that include fully no-take reserves. Fish response to protection can thus be used to evaluate the effectiveness of marine reserves. Most target fish are high-level predators and their overfishing may affect entire communities through trophic cascades. In the Mediterranean rocky sublittoral, marine reserves may allow fish predators of sea urchins to recover and thus whole communities to be restored from coralline barrens to macroalgae. Such direct and indirect reserve effects, however, are likely to be related to the enforcement implemented. In Italy, many MPAs that include no-take reserves have been declared, but little effort has been spent to enforce them. This is a worldwide phenomenon (although more common in some regions than others) that may cause MPAs and reserves to fail to meet their targets. We found that 3 of 15 Italian marine reserves investigated had adequate enforcement, and that patterns of recovery of target fish were related to enforcement. No responses were detected when all reserves were analyzed as a whole, suggesting enforcement as an important factor to be considered in future studies particularly to avoid that positive ecological responses in properly managed reserves can be masked by neutral/negative results in paper parks. Positive responses were observed for large piscivores (e.g. dusky groupers) and sea urchin predators at reserves where enforcement was effective. Those reserves with low or null enforcement did not differ from fished areas.

In both protected and fished rocky reefs in the southern Adriatic Sea, the behaviour of the sea breams Diplodus sargus and D. vulgaris (both targeted by spear-fishing) in the presence of divers was found to be mostly negative (i.e. escape response). However, at protected reefs sea breams frequently swam into the closest shelters, whereas in fished reefs they mostly escaped in open water. This study suggests that spear-fishing may alter the escape response of fish from natural predators and that marine reserves may re-establish natural behaviour patterns.

Man-made defence structures (e.g., breakwaters, jetties) are becoming common features of marine coastal landscapes all around the world. The ecology of assemblages of species associated with such artificial structures is, however, poorly known. In this study, we evaluated the density and size of fish predators of echinoids (i.e., Diplodus sargus, Diplodus vulgaris, Sparus aurata), and the density of sea urchins (i.e., Paracentrotus lividus) at defence structures (i.e., breakwaters) inside and outside the marine protected area of Miramare (northern Adriatic Sea) in order to: (1) assess possible differences in fish predator density and size between protected and fished breakwaters; (2) assess whether fish predation may have the potential to affect sea urchin density in artificial rocky habitats. Surveys were carried out at four random times over a period of two years. Total density, and density of medium- and large-sized individuals of the three predatory fishes were generally greater at the protected than at the fished breakwaters, whereas no differences were detected in the density of small-sized individuals. Density of the sea urchin P. lividus did not show any difference between protected and fished breakwaters. The results of this study suggest that: (1) protection may significantly affect predatory fishes in artificial rocky habitats; (2) differences in predatory fish density, and size may be unrelated with the density of the sea urchin P. lividus; (3) protected artificial structures such as breakwaters, originally planned for other purposes, could represent a potential tool for fish population recovery and enhancement of local fisheries.