Using spatial distribution modeling of commercial species to inform management of small-scale fisheries in a Mediterranean marine protected area.

Marine protected areas (MPAs) make an essential contribution to the spatial management of critical areas, the conservation of coastal species exploited by human activities, and the sustainable use of marine resources. Within MPAs, fishing closure areas are among the most used small-scale fishery management tools, even though their effectiveness largely remains untested or controversial. To reduce the impact of small-scale fisheries on marine resources, a seasonal fishing closure area (SFCA) was established beginning in 2022 in autumn-winter season inside the Capo Caccia-Isola Piana MPA (Sardinia, northwestern Mediterranean Sea). Here, we assessed a posteriori whether the areas of higher habitat suitability for eight species/taxa of relevant ecological value and economic interest to small-scale fisheries were included in the established SFCA, adequately meeting the ecological objectives of the MPA. Thus, landing data (from 2019 to 2023) were used as occurrence records to develop MaxEnt distribution models for the eight target species/taxa. The model outputs allow us to draw important insights about the spatial adequacy of the SFCA established within the MPA aimed to protect the most exploited marine resources. Furthermore, the modeling exercises were useful for understanding the local processes influencing species' habitat selection and to identify essential areas for the target species that could remain unrevealed in larger-scale investigations.

Towards a sustainable fisher-dolphin coexistence: Understanding depredation, assessing economic damage and evaluating management options.

Finding solutions for a sustainable coexistence between wildlife and humans is considered among the most challenging environmental management issues for scientists, conservationists, managers, and stockholders world-wide. Depredation by the common bottlenose dolphin (Tursiops truncatus) on small scale fisheries has increased in the recent years, leading to a growing conflict in many areas of the Mediterranean Sea and pressing for urgent management solutions. This study aims at developing a management framework for a sustainable coexistence between fishers and dolphins in Sardinia (Mediterranean Sea). Relying on the combination of different approaches (field study, literature review and Multi Criteria Decision Analysis), the scientific evidence necessary for understanding dolphin depredation were updated and improved, the related economic damage was calculated, and different management options were identified and evaluated by several stakeholder groups to support the decision-making process. Averaging for all investigated net types (gillnet and trammel net), a depredation frequency of 53% was found, the highest values ever found in both Sardinia and many other Mediterranean sites. Depredation probability was influenced by different factors, such as net type, fishing operation duration, depth of the fishing site and period. The estimated economic damage due to depredation ranges on average between 6492 and 11,925 euro per year and depends on the type of fishing net. The results from the field study, the literature review and the stakeholder involvement allowed us to define the most plausible and shared management options, identifying a framework for assessing and managing the conflict between fishers and dolphins for the creation of a more sustainable vision for the future.

Variations in coralligenous assemblages from local to biogeographic spatial scale.

The present study aims at contributing to the knowledge of the spatial variability of coralligenous reefs through the evaluation of patterns ranging from local to biogeographic scale around the island of Sardinia. The coralligenous reef assemblages of six areas were studied through a hierarchical sampling design: three sites per area were selected, in each site three plots were sampled and in each plot ten photographic samples were collected. The structure of coralligenous reefs across closed biogeographic regions is described, highlighting that nearly pristine assemblages, although characterized by similar high diversity, can be either dominated by animals, such as gorgonians and bryozoans, or macroalgae. The observed variations seem largely related to biogeographic patterns rather than spatial distance, supporting the need to identify specific reference conditions to assess the ecological quality of this habitat depending on the biogeographic area to be monitored.

Extreme events and conservation of subtidal habitats: Effects of a rainfall flood on coralligenous reefs.

The increase of the intensity and frequency of rainfall-dominated flood is considered a main effect of climate change. The present study evaluated the effect of a rainfall flood event on coralligenous reefs. The flooded site was compared to three control sites using a Before/After-Control/Impact (BACI) design. Sites were sampled using the STAR (STAndaRdized coralligenous evaluation procedure) approach and three ecological indices (ESCA, COARSE and ISLA) were calculated. At the disturbed site the number of species per sample, beta diversity, sensitivity levels of assemblages and the values of the three indices were lower after the flooding event, while the same variables did not decrease at the control sites. Algal turf and Dictyotales increased at the disturbed sites after the flood event, while Udoteaceae, erect sponges, bryozoans and Corallium rubrum decreased. This study provides evidence for identifying floods as a further cause of degradation for the coralligenous reef assemblages.

Macroalgal forest vs sea urchin barren: Patterns of macro-zoobenthic diversity in a large-scale Mediterranean study.

The study aimed at contributing to the knowledge of alternative stable states by evaluating the differences of mobile and sessile macro-zoobenthic assemblages between sea urchin barrens and macroalgal forests in coastal Mediterranean systems considering a large spatial scale. Six sites (100 s km apart) were selected: Croatia, Montenegro, Sicily (Italy), Sardinia (Italy), Tuscany (Italy), and Balearic Islands (Spain). A total of 531 taxa, 404 mobile and 127 sessile macro-invertebrates were recorded. Overall, 496 and 201 taxa were found in macroalgal forests and in barrens, respectively. The results of this large-scale descriptive study have met the expectation of lower macrofauna complexity and diversity in barrens rather than in macroalgal forests, and have allowed estimating the differences in levels of diversity and the consistency of variability across Mediterranean sites. Some peculiar patterns in barrens, related to both abundance of specific taxa and to high values of beta diversity, have been evidenced.

Benthic mucilage blooms threaten coralligenous reefs.

Mucilaginous aggregates produced by planktonic or benthic algae are considered ecological threats to marine systems. The study evaluated the effects of the spread of benthic mucilaginous aggregates on the structure of coralligenous assemblages. The assemblage and the quality of a site subjected to a benthic mucilage bloom were compared to those of two reference sites using a Before/After-Control/Impact (BACI) design. Results showed the α and ß-diversity, ESCA and COARSE quality ecological indices and the cover of encrusting algae and bryozoans were lower at the impact site after the mucilage event than at the control sites and at the impact site before the mucilage event. An opposite pattern was observed for the necrosis of gorgonians and the cover of algal turf. This study describes for the first time the impacts of ephemeral mucilage blooms on the whole coralligenous assemblage, identifying a further threat of this habitat and the need of adequate monitoring programs.

ALEX index enables detection of alien macroalgae invasions across habitats within a marine protected area.

A modified version of the ALien Biotic IndEX (ALEX) has been recently proposed to evaluate biological invasions in macroalgal assemblages. ALEX was applied in a Marine Protected Area where a recreational-fishing port is present testing the following hypotheses: ALEX increases with the distance from the port, it changes between the two directions off the port and it changes among three different habitats: Cystoseira beds, algal turf and dead matte of the seagrass Posidonia oceanica. A total of 78 native macroalgal taxa and 4 introduced species were found, the Chlorophyta Caulerpa cylindracea and the Rhodophyta Apoglossum gregarium, Acrothamnion preissii and Womersleyella setacea. All study sites were in high quality status highlighting that the assemblages investigated were at an early stage of NIS invasion. However, ALEX detected different values among conditions and habitats within the MPA, suggesting a local dynamics of NIS spread and different resistance to invasion of the investigated habitats.

The detrimental consequences for seagrass of ineffective marine park management related to boat anchoring.

Posidonia oceanica (L.) Delile meadows are recognized as priority habitat for conservation by the EU Habitats Directive. The La Maddalena Archipelago National Park (Mediterranean Sea) P. oceanica meadow, the dominant coastal habitat of the area, is mostly threatened by boat anchoring. 12 years after the establishment of mooring fields and anchoring restrictions, a study was conducted to measure their effectiveness on the conservation of seagrass and the mitigation of anchoring damage. We found that: (i) the condition of P. oceanica was disturbed, both in the mooring fields and in control locations; (ii) mooring fields and anchoring restrictions did not show to be an efficient system for the protection of seagrass, in fact anchor scars increased after the tourist season; (iii) the mooring systems had an impact on the surrounding area of the meadow, probably due to their misuse. On the basis of these results, management recommendations for marine parks are proposed.

Detection of low abundance mRNA of myeloid specific genes in cells of acute and chronic lymphoid leukemias by cRNA hybridization.

The hybridization to a complementary RNA (cRNA) probe both in situ and in solution was used to assay tiny amounts of mRNA of the lactoferrin (LF) and myeloperoxidase (MPO) genes in normal bone marrow cells and in acute and chronic lymphoid leukemias. Evidence is reported that this technique is much more sensitive than the standard Northern blot technique. The LF mRNA was detectable in three of seven cases of acute lymphoblastic leukemia (ALL) and in three of seven cases of chronic lymphocytic leukemia (CLL). Four cases of ALL were also positive when tested with the MPO cRNA. It is apparent from these results that myeloid specific mRNA, different from MPO, may be detected in leukemic cells with lymphoid phenotype using a method more sensitive than the Northern blot technique. Whether or not the molecular events observed in these cell populations reflect events physiologically occurring rather than a deregulation of gene expression associated to leukemogenesis remains to be established.