M. Sciberras

Fisheries reserves (FRs) are spatially bounded areas where the harvesting of fisheries resources is restricted, according to gear types (restricted fishing areas), or forbidden (no-take zones) and are designed to protect populations of commercially important stocks from overexploitation. However, such reserves may also protect vulnerable and ecologically important habitats especially if the reserve size is relatively large enough to include significant areas of such habitats, even if the focus of the reserve is not habitat protection. We illustrate this using the 25 nautical mile Maltese Fisheries Management Zone (FMZ) as a case study. Since 1971, Malta has managed a 25 Nautical Mile Exclusive Fishing Zone, covering an area of 10,700 km2, which, after Malta became a member of the European Union in 2004, was retained as a Fisheries Management Zone (FMZ). The objectives of the original Exclusive Fishing Zone were to protect the local artisanal fisheries from large scale fishing by, am...

ABSTRACT Background Marine Protected Areas (MPAs) encompass a range of protection levels, from fully protected no-take areas to restriction of only particular activities, gear types, user groups, target species or extraction periods. We synthesized the results of empirical studies that compared partially protected areas (PPA) to (i) no-take marine reserves (NTR) and (ii) to open access areas (Open), to assess the potential benefits of different levels of protection for fish and invertebrate populations. Methods A systematic search for relevant articles used terms describing MPAs, the biota (e.g. fish, invertebrates) and measures (e.g. density, biomass) of interest. Articles were examined for relevance using specified inclusion criteria. Included articles were appraised critically; the influence of studies whose effect of protection was identified to be confounded by habitat was examined by running a sensitivity analysis parallel to the main analysis that included all studies. Random effect meta-analysis on ln-transformed response ratios was used to examine the response to protection. Subgroup analyses and meta-regression were used to explore variation in effectiveness in relation to MPA and species covariates. Results Synthesis of available evidence suggests that while PPAs resulted in higher values of biological metrics (density and biomass) than unprotected areas, greatest benefits were apparent in NTR areas when NTRs and PPAs were compared. For fish, the positive response to protection, whether full or partial protection, was primarily driven by targeted fish species. Although positive benefits were also apparent in non-target fish species, the results were more variable, perhaps because of fewer studies focusing on this group. Invertebrate studies were underrepresented and those available focused mainly on scallops, lobsters and sea urchins. Among the targeted species groups, benefits from partial protection relative to fished areas were highest for scallops, whereas benefits from full relative to partial protection were highest for lobsters. The examination of fish and invertebrate response to protection in terms of species richness and length was hampered by small sample sizes. There was significant variability in the magnitude of response to protection among the MPAs included in this study. The factors determining such variation were generally unclear although the size and protection regime of the PPA explained some of this variability. Conclusions The available evidence suggests that no-take reserves provide some benefit over less protected areas, nevertheless the significant ecological effects of partially protected areas relative to open access areas suggest that partially protected areas are a valuable spatial management tool particularly in areas where exclusion of all extractive activities is not a socio-economically and politically viable option. A glossary of terms is given in Appendix. Registration number CEE-09-018

ABSTRACT Fishing with bottom towed gear is widely considered an invasive form of fishing in terms of its impacts upon seabed habitats and fauna. Fishery closures or marine protected areas provide baseline conditions against which to assess the response to the removal of fishing disturbance and thus shed light on their use as fisheries management tools. We conducted repeat underwater camera surveys inside a recently established area that is permanently closed to scallop fishing and a seasonally fished area in Cardigan Bay, UK, to test for differences in scallop abundance and epibenthic community structure and to examine recovery processes over a 23 mo study period. Changes in scallop density and epifaunal diversity and community composition were primarily driven by seasonal fluctuations; no differences were found between the permanently closed area and the seasonally fished area. Temporal changes in epibenthic community inside the permanently closed area were not related to recovery processes associated with the cessation of scallop dredging. Sediment composition and bedforms shifted between surveys, suggesting that this community is exposed to a dynamic environment. It is likely that scallop dredging at the present levels of fishing may be insufficient to induce changes large enough to be detected in the presence of strong natural disturbance. We highlight the importance of considering the physical nature and dynamics of the environment and the nature of the species concerned throughout the process of designating closed areas, to avoid negative impacts on fisheries and limited conservation benefits.

ABSTRACT Spatial and bathymetric distribution, population density, habitat preferences, fecundity, breeding season and interspecific interactions of the alien grapsoid crab Percnon gibbesi (H. Milne-Edwards, 1853) from the Maltese Islands (Malta and Gozo) are compared among localities in the Mediterranean where established populations have been reported since 1999. In the Maltese Islands, habitat preferences and bathymetric distribution were similar to those in other Mediterranean localities. Spatial distribution was found to be limited by the availability of the boulder habitat in which this crab nearly always occurs. Fecundity was higher in the Maltese Islands than in Linosa and Lampedusa, the breeding season lasting from the end of May until September. On Maltese shores the habitat of the alien overlapped with that of the native grapsid Pachygrapsus marmoratus (Fabricius, 1787) (Crustacea: Brachyura: Grapsoidea) and, to a lesser extent, that of the native xanthid Eriphia verrucosa (Forska°l, 1775). Laboratory studies to assess the possible interactions of the alien species with P. marmoratus suggest that the latter shows a competitive advantage over P. gibbesi, since 80.8% of encounters between the two species were initiated by P. marmoratus, and in 80% of the encounters it prevailed. This suggests that P. marmoratus is unlikely to be excluded from its natural habitat by the alien species, and that significant spatial resource partitioning on the part of P. marmoratus is unlikely to occur.

ABSTRACT The establishment of marine protected areas (MPAs), particularly of no-take areas, is often viewed as a conflict between conservation and fishing. Partially protected areas (PPAs) that restrict some extractive uses are often regarded as a balance between biodiversity conservation and socio-economic viability. Few attempts have been made to generalize the ecological effects of PPAs. We synthesized the results of empirical studies that compared PPAs to (i) no-take reserves (NTRs) and (ii) to open access (Open) areas, to assess the potential benefits of different levels of protection for fish populations. Response to protection was examined in relation to MPA parameters and the exploitation status of fish. Our syntheses suggest that while PPAs significantly enhance density and biomass of fish relative to Open areas, NTRs yielded significantly higher biomass of fish within their boundaries relative to PPAs. The positive response to protection was primarily driven by target species. There was a large degree of variability in the magnitude of response to protection, although the size of the PPA explained some of this variability. The protection regime within the PPA provided useful insights into the effectiveness of partial MPAs. We conclude that MPAs with partial protection confer advantages, such as enhanced density and biomass of fish, compared to areas with no restrictions, although the strongest responses occurred for areas with total exclusion. Thus, MPAs with a combination of protection levels are a valuable spatial management tool particularly in areas where exclusion of all activities is not a socio-economically and politically viable option.