Exposure to Ostreopsis cf. ovata blooms on beaches with a temperate climate causes acute mild symptoms through direct contact with seawater or suspected airborne irritant compounds. To design protective measures and minimize harmful effects on humans, a two-year (2024–2025) health impact study was conducted on scientists involved in regular sampling and research on these events. In 2024, this scientific cohort recorded their symptoms during sampling on a rocky beach in the northwestern Mediterranean where recurrent summer Ostreopsis cf. ovata blooms occur. The collected data were compared with previous epidemiological studies carried out from 2013 to 2018 at the same site in a general-public cohort. The present study corroborated previous findings, i.e. symptoms were related to seven systems of the human body, were of short duration and typically resolved spontaneously without medical intervention. However, additional symptoms were experienced by the scientific cohort. Based on all the observations, preventive and protective measures were designed and implemented during sampling in 2025 and proved effective. Nevertheless, potential chronic effects caused by repeated acute exposures cannot be ruled out and require further research.
The arrival of massive jellyfish swarms threatens coastal ecosystem services and human health, particularly in the Alboran Sea, a complex ecoregion that includes the Costa del Sol, a major tourism hub. This study investigates the oceanographic mechanisms driving the interannual variability of these events. Complementary methods were applied, including particle dispersion modelling validated against observational data, mainly stranding reports. Coastal occurrences of Pelagia noctiluca vary strongly between summers of high abundance and periods of near absence. This variability appears closely linked to the origin of water masses reaching the Alboran coast. Summers with high jellyfish abundance are associated with populations originating within the Alboran Sea and adjacent Algerian Basin, whereas such events are rare when northern Mediterranean regions serve as the source. Intensification of the Alboran gyres may enhance aggregation and retention under high-productivity conditions, reinforcing these patterns. Dispersal and advection from different source regions appear to play a central role in the interannual dynamics of jellyfish swarms. By linking medium- and large-scale oceanographic processes to the full eight-month life cycle of P. noctiluca, this study identifies the temporal windows controlling swarm development. These insights improve forecasting of coastal jellyfish events and support early-warning systems and management strategies.
The seafood industry of Saint Pierre and Miquelon (SPM) was severely impacted by the collapse of the Eastern Canadian cod fishery, which led to the 1992 moratorium. This underscored the need for diversification strategies to sustain the local economy. Scallop aquaculture (Placopecten magellanicus) has since been developed on a limited scale, but spatial expansion is required to ensure long-term economic viability. In 2008, a comprehensive research and development programme was launched to address this need. This study focuses on the critical stage of site selection, applying a GIS-based multi-criteria approach to identify suitable areas for on-bottom scallop aquaculture. Acoustic and video surveys, combined with ground-truthing, produced the first large-scale seabed habitat maps of eastern SPM. These maps also provide a geospatial database to support coastal zone management and decision-making in the archipelago. The results identified 8335 ha suitable for aquaculture, subdivided into areas for public stock enhancement and leasing grounds for private operations. Suitable areas are not a limiting factor for expansion, and a 2724-ha zone was identified as the most appropriate for leasing, supporting a potential annual production of ~100 t, based on existing equipment and a current five-year rearing cycle at 4 ind. m–². Habitat characterization also enables optimal matching of dredge types (New Bedford vs toothed crossbar) to seabed conditions, minimizing future benthic impacts. Management recommendations and research priorities are discussed, with particular emphasis on addressing the availability of juveniles for seeding. Large-scale development is constrained by juvenile supply, necessitating optimization of spat collection and/or hatchery production. These findings lay the foundation for a strategic aquaculture growth plan, positioning scallop farming as a key contributor to the long-term economic resilience of the SPM archipelago alongside traditional fisheries.
Tag recoveries from a more than 40-year tagging programme of loggerhead turtles nesting at the three major nesting areas of Greece (Zakynthos, Kyparissia Bay, Rethymno) revealed their post-nesting whereabouts in the Mediterranean. Most tag recoveries, signalling potential foraging areas, occurred in the Central Mediterranean, with major concentrations in the Adriatic Sea and the Tunisian Plateau (both characterized by shallow waters and rich benthic fauna), whereas fewer recoveries were recorded in the Aegean Sea. While turtles from Zakynthos and Kyparissia Bay shared the Adriatic Sea and the Tunisian Plateau, turtles from Rethymno (Crete) preferred the Aegean Sea and the Levantine Sea. Tag recoveries showed a much wider dispersal of post-nesting turtles than the dispersal recorded from satellite telemetry, highlighting the benefits of long-term tagging programmes. More than 60% of the recovered turtles were reported dead, indicating the substantial threats that reproductively active individuals, the most biologically valuable group in the loggerhead population, face in the Mediterranean Sea.
