The West Gironde Mud Patch (WGMP) is a mud deposit located 25 km from the mouth of the Gironde Estuary in the Bay of Biscay. This 4-metre-thick clay-silt feature, which extends over an area of 420 km2, is found at depths between 30 and 80 meters. The main objectives of the JERICObent7 cruise, in July 2019, were to characterise the evolution of the WGMP’s benthic ecosystem in terms of its sedimentary, biogeochemical and ecological properties and to reconstruct climate variations and identify potential anthropogenic impacts over the last few centuries. To this end, a precise chronological framework was established for the sedimentary archives of the last few decades using 210Pbxs (T1/2 = 22.3 years). Interface cores were collected at stations 1, 3 and 4 along a cross-shelf transect. Twin Kullenberg cores were collected at sites 3 and 4 for geochemical (KGL) and palaeoceanographic (JB7-ST) investigations. Each interface core was carefully extruded at 0.5 cm intervals from the top of the core to 4 cm, and then at 1 cm intervals until the bottom was reached. Kullenberg cores were only collected at sites 3 and 4. Depending on their intended use, the Kullenberg cores were sampled at different resolutions, the depth of each sediment layer corresponded to the depth from the top of the core. These layers were then used to determine the dry bulk density and radioisotope activities of interest (210Pb, 226Ra,  228Th, 137Cs, 40K). Excess 210Pb was used to establish the realignment and chronological framework of the interface and Kullenberg cores.

The dataset includes age- and length-based catch per unit effort data for commercial fish species collected by the French trawl survey EVHOE.

The SOMLIT-Antioche observation station, located at 5 nautical miles from Chef de Baie harbor (La Rochelle) is part of the French monitoring network SOMLIT (https://www.somlit.fr/), accredited by the INSU-CNRS as a national Earth Science Observatory (Service National d’Observation : SNO), which comprises 12 observation stations distributed throughout France in coastal locations. It aims to detect long-term changes  of these ecosystems under both natural and anthropogenic forcings. SOMLIT is part of the national research infrastructure for coastal ocean observation ILICO (https://www.ir-ilico.fr/?PagePrincipale&lang=en). The SOMLIT-Antioche station (46.0842 °N, 1.30833 °W) is located in the north-eastern part of the Bay of Biscay, halfway between the islands of Ré and Oléron, at the centre of what is commonly known as the Pertuis Charentais area, which correspond to a semi-enclosed shallow basin and includes four islands (Ré, Oléron, Aix and Madame) and three Pertuis (i.e., detroit) (Breton, Antioche and Maumusson). This 40m-deep site, with muddy to sandy marine bottoms, is submitted to a macro-tidal regime and is largely open to the prevailing westerly swells. It remains under a dominant oceanic/neritic influence, even though its winter/spring hydrological context is influenced by the diluted plumes of the Charente, Gironde and Loire rivers, but not by those of too small estuaries (Lay, Seudre and Sèvre Niortaise). SOMLIT-Antioche hydrological monitoring has been carried out by the LIENSs/OASU laboratory on a fortnightly basis since June 2011. Surface water samples are collected  at high-tide during intermediate tides (70 ± 10 in SHOM units) on board the research  vessel ‘L’Estran’ owned by La Rochelle University. Samples are analyzed for more than 16 core parameters: temperature, salinity, dissolved oxygen, pH, ammonia, nitrates, nitrites, phosphates, silicates, suspended matter, particulate organic carbone, particulate organic nitrogen, chlorophyll, delta15N, delta13C; pico- and nano- plankton. Measurements are carried out in accordance with the ISO/IEC 17025:2017 standard. Simultaneous monitoring of the micro-phytoplankton community (since 2013, SNO PHYTOBS: https://www.phytobs.fr/en) and monitoring of prokaryotic communities (Bacteria and Archaea) are also carried out on a monthly basis. Since 2019, seasonal observations of benthic invertebrate communities (SNO BenthObs : https://www.benthobs.fr/) have also been carried out. This monitoring is complementary to that carried out at hydrological stations in the pre-existing REPHY and DCE networks, some of which are located near marine farming areas (oyster and mussel farms).

210Pb, 226Ra and 137Cs were measured by non-destructive gamma spectrometry on marine sediment cores, collected during RIKEAU 2002 cruise on board r/v Thalia, on the shelf of the Bay of Biscay

The Arcachon Bay is a unique and ecologically important meso-tidal lagoon on the Atlantic coast of south-west France. The Arcachon Bay has the largest area of dwarf seagrass (Z. noltei) in Europe, the extent of which was stable in their extent between the 1950s and 1990s, but a decline in seagrass was observed in mid-2000. The decline of Zostera (seagrass) may have a significant impact on sedimentation in this coastal ecosystem rich in marine life. Interface cores were collected in September 2022 to determine sediment and mass accumulation rates (SAR, MAR) in the Arcachon Bay. Ten study areas were selected, distributed over most of the areas where seagrass meadows are actually observed. Two sites were visited each time, one with the presence of Zostera noltei in good condition (Healthy) and the other where the sediment was bare (Bare). Maximum water heights during spring tides range from 3.44 m for the deepest site (Garrèche) to 2.09 m for the shallowest site (Fontaines). A total of 20 sediment cores were sampled and carefully extruded every 1 cm from the top to the bottom of the core. The sediment layers were used to determine dry bulk density and selected radioisotope activities: DBD, 210Pb, 226Ra, 137Cs, 228Th and 40K expressed as %K). 

Global Fishing Watch is working across the globe to provide governments and authorities with actionable reports and capacity building to help strengthen fisheries monitoring and compliance. Our global team of experts produce analyses to inform monitoring, control and surveillance of fisheries in five key areas: - Illegal, unreported and unregulated fishing - Transshipment - Port controls - Marine protected areas - Operation support Collaboration and information sharing are integral to achieving well-managed fisheries. By working with stakeholders and making analyses available to national, regional and intergovernmental partners, Global Fishing Watch is enabling fisheries agencies to make more informed and cost-efficient decisions. Topics: - Commercial fishing, Global Fishing Watch is harnessing innovative technology to turn transparent data into actionable information and drive tangible change in the way that fisheries are governed. - Transshipment, Through publicly sharing map visualisations and creating data and analysis tools, we seek to inform management and policy efforts and provide a more complete picture of transshipment at sea. - Marine protected areas, Global Fishing Watch is harnessing the data and technology revolution to support the effective design, management and monitoring of marine protected areas.

For the 21 years of the study, an examination of trends in chlorophyll concentration revealed a general decline throughout the Gulf over the production period. These trends, extracted from dynamic linear model, also allowed this decline to be quantified. Expressed as a percentage, a large part of the area below the 50 m bathymetric line showed a decrease of at least 10% over the period, corresponding to a value of at least 0.1 µg.l-1. However, the spatial distribution reveals some more local phenomena. In southern Brittany, from Quimper to Vannes, a particular feature appears, with an upward trend over several kilometres along the coast, followed by a pronounced gradient along the coast. This gradient includes a zone where a continuous monotonic increasing trend is observed, then a zone where the trend becomes not significant and finally, about 15 km from the coast, a new zone where a significant continuous monotonic decreasing trend is observed. The increase in chlorophyll a concentration in the very coastal part is greater than 0.1 µg.l-1 over the period. Another peculiarity concerns the central part, located at the edge of the plateau at Cap Ferrat and Pente Aquitaine, where an increase in chlorophyll a was observed, but the variations remained small, being less than 0.1 µg.l-1. About a hundred kilometres south-west of Saint Nazaire, an area of about 40 by 50 km shows a decrease in chlorophyll a of more than 20%, quantified as more than 0.1 µg.l-1 over the period.

Tracking data of 7 grey seals were obtained from the deployment of Fastloc GPS/GSM tags developed by the Sea Mammal Research Unit (UK). Full tag description is available at: http://www.smru.st-andrews.ac.uk/Instrumentation/GPSPhoneTag/. The tags include a wet-dry sensor from which haulout events are recorded, a pressure sensor providing detailed dive data, as well as a Fastloc GPS recording irregular locations when the seal is not underwater. Data is stored onboard and transmitted via the GSM network when the seal is in the reception range. The data provided here are the individual GPS locations of the seals fitted with these tags for an average duration of 135 days.

This dataset contains bio-optical measurements and environmental parameters associated with  Deep Chlorophyll Maxima acquired by BGC-Argo profiling floats and matched with mesoscale eddies location from the Ocean Eddy Detection and Tracking Algorithms (TOEeddies) Atlas. For each BGC-Argo profile the data files includes the World Meteorological Organistion (WMO) and profile numbers, geographical position (LON and LAT), the date of the profile in Julian Day (JULD); the qualification of the vertical profile (CARAC_BIO) as Deep Biomass Maximum (DBM), Deep photoAcclimation Maximum (DAM), or presenting no DCM (NO); at the depth of the maximum (DCM_DEPTH), the chlorophyll a concentration (CHLA_DCM, mg chla m-3 ) and the backscattering coefficient (BBP_DCM, m-1); the Mixed Layer Depth (MLD, m), the nitracline depth (NCLINE, m), the mean daily Available PAR in the Mixed Layer Depth (MIPAR_MLD, E m -1 d -1), the daily Available PAR at the nitracline depth (IPAR_NCLINE, E m-2 d-1); the location of the profile (CARAC_EDDY) as being inside the core/periphery (IN/_EN) of a cyclonic/anticyclonic eddy (DEP_/P_), or outside eddy influence (OUT); the processing level (MODE) of the ADT maps used for the TOEddies detection, either Near Real Time (-1), or Delayed Mode (1). The qualification and processing of the BGC-Argo profiles, as well as the DCM detection (DAM/DBM/NO) and the estimation of the environmental parameters, were applied as described from Cornec, M., Claustre, H., Mignot, A., Guidi, L., Lacour, L., Poteau, A., D'Ortenzio, F., Gentili, B., Schmechtig, C.  (2021). Deep chlorophyll maxima in the global ocean: Occurrences, drivers and characteristics. Global Biogeochem Cycles 35. https://doi.org/10.1029/2020GB006759 Data relative to mesoscale eddies were produced by processing daily 0.25°x0.25° AVISO Absolute Dynamical Topography (maps produced by Ssalto/Duacs and distributed by Copernicus-Marine Environment Services) with the TOEddies algorithm (Laxenaire, R., Speich, S., Blanke, B., Chaigneau, A., Pegliasco, C., & Stegner, A. (2018). Anticyclonic Eddies Connecting the Western Boundaries of Indian and Atlantic Oceans. Journal of Geophysical Research: Oceans, 123(11), 7651–7677. https://doi.org/10.1029/2018JC014270)