The COVID-19 pandemic has resulted in unparalleled global impacts on human mobility. In the ocean, ship-based activities are thought to have been impacted due to severe restrictions on human movements and changes in consumption. Here, we quantify and map global change in marine traffic during the first half of 2020. There were decreases in 70.2% of Exclusive Economic Zones but changes varied spatially and temporally in alignment with confinement measures. Global declines peaked in April, with a reduction in traffic occupancy of 1.4% and decreases found across 54.8% of the sampling units. Passenger vessels presented more marked and longer lasting decreases. A regional assessment in the Western Mediterranean Sea gave further insights regarding the pace of recovery and long-term changes. Our approach provides guidance for large-scale monitoring of the progress and potential effects of COVID-19 on vessel traffic that may subsequently influence the blue economy and ocean health.

We examined the short-term movements of a small temperate fish, the painted comber Serranus scriba (Linnaeus 1758), within the marine protected area (MPA) of Palma Bay (NW Mediterranean) using passive acoustic telemetry. Fifteen adults were surgically implanted with acoustic transmitters and monitored between July 2007 and February 2008 for periods of up to 36 d. Interindividual variability was detected for both spatial and temporal patterns. There were 2 principal movement behaviours that were recorded, with some individuals showing high site fidelity and others showing a more mobile behaviour, moving out from the monitoring area. Observation-area curves indicated that a period between 3 and 5 d was required to determine home ranges of the sedentary fish. Home range sizes were small, with a minimum shift of core areas occurring on a daily basis. Total minimum convex polygon (MCP) areas ranged between 0.102 and 0.671 km2, whereas 95% kernel utilization distributions (KUD) ranged between 0.760 and 1.333 km2. Core areas (50% KUD) ranged between 0.175 and 0.294 km2. There were no significant differences in home range patterns between day and night periods. However, the use of the continuous wavelet transform (CWT) revealed diel rhythms on the detection pattern that could be related to a resting behaviour at night. Estimation of home ranges of S. scriba agrees with the sedentary habits of the Serranidae family and suggests the potential use of MPAs for the sustainable development of the fishery of this small Serranid.Peer reviewe

New monitoring technologies are being progressively implemented in open-ocean and coastal observatories. The Mediterranean Sea is a well-known, reduced-scale ocean, an ideal natural laboratory to study global ocean processes, in particular those associated with meso- and submesoscale variability, interactions with mean flows and associated ecosystem response. SOCIB, the Balearic Islands Coastal Ocean Observing and Forecasting System, is one of such observatories, a multiplatform distributed and integrated system, a facility of facilities that extends from the nearshore to the open sea. SOCIB profits from the strategic position of the Balearic Islands at the Atlantic/Mediterranean transition area, one of the “hot spots” of biodiversity in the world’s oceans, and also of societal needs in islands where preservation of the environment is essential to assure both residents’ welfare and the competitiveness of the tourist sector. SOCIB is unique in that, from peer-reviewed excellence, its mission and objectives are science-, technology-, and society-driven. These types of new marine infrastructures, because of their critical mass and sustained funding, are presently establishing new ways of international cooperation, leading to major science breakthroughs, innovations in oceanographic instrumentation, and new ways of more efficient and science-based coastal and ocean management. We describe the major elements and structure of SOCIB and present some recent scientific, technological, and society-related results that are of relevance at a global ocean scale.

The Mediterranean community represented in this paper is the result of more than 30 years of EU and nationally funded coordination, which has led to key contributions in science concepts and operational initiatives. Together with the establishment of operational services, the community has coordinated with universities, research centers, research infrastructures and private companies to implement advanced multi-platform and integrated observing and forecasting systems that facilitate the advancement of operational services, scientific achievements and mission-oriented innovation. Thus, the community can respond to societal challenges and stakeholders needs, developing a variety of fit-for-purpose services such as the Copernicus Marine Service. The combination of state-of-the-art observations and forecasting provides new opportunities for downstream services in response to the needs of the heavily populated Mediterranean coastal areas and to climate change. The challenge over the next decade is to sustain ocean observations within the research community, to monitor the variability at small scales, e.g., the mesoscale/submesoscale, to resolve the sub-basin/seasonal and inter-annual variability in the circulation, and thus establish the decadal variability, understand and correct the model-associated biases and to enhance model-data integration and ensemble forecasting for uncertainty estimation. Better knowledge and understanding of the level of Mediterranean variability will enable a subsequent evaluation of the impacts and mitigation of the effect of human activities and climate change on the biodiversity and the ecosystem, which will support environmental assessments and decisions. Further challenges include extending the science-based added-value products into societal relevant downstream services and engaging with communities to build initiatives that will contribute to the 2030 Agenda and more specifically to SDG14 and the UN's Decade of Ocean Science for sustainable development, by this contributing to bridge the science-policy gap. The Mediterranean observing and forecasting capacity was built on the basis of community best practices in monitoring and modeling, and can serve as a basis for the development of an integrated global ocean observing system.

We used acoustic telemetry to describe the spatial and temporal patterns of habitat use of one of the species most targeted by recreational anglers in the NW Mediterranean, Serranus cabrilla (Linnaeus, 1758). Temporal patterns and fish position were determined using a fixed-receiver array located in a marine protected area (MPA) in Palma Bay (Balearic Islands). Fish position as centre of activity (COA, the centre of the area the fish uses during a specific time) and space utilisation preferences could be described due to a receiver array design with a high range detection overlap (more densely distributed near the COA). There were significantly more detections per time unit during the day, which was interpreted as increased activity possibly related to feeding habits and social behaviour. S. cabrilla spent 95% of its time in an average area of 0.77 ± 0.17 km2, with a core area (50% of the time) of 0.10 ± 0.29 km2. The home range size was not related to fish size or diel pattern (i.e. the size of the daytime home range was not significantly different from the night range). The linearity index and the index of reuse (proxies of site fidelity) also demonstrated that this species has high site fidelity, which suggests that it is sedentary with a limited adult dispersal capacity. Two main habitats were observed in the study area, and S. cabrilla spent on average much less time in seagrass meadows (Posidonia oceanica beds) compared to soft, gravel and detritus bottoms. A relatively small MPA would be a useful management tool for establishing sustainable exploitation levels of this species. © Inter-Research 2011.This study was financed by the research project CONFLICT (CGL2008- 00958) funded by the Spanish Ministry of Science and InnovationPeer Reviewe