The associated data highlights the sampling programme for the data acquisition campaign of Observation on the Aerial Platform for the SAMM1and SAMM2 campaigns (Aerial Marine Megafauna Monitoring) conducted by the PELAGIS observatory (UMS 3462 ULR/CNRS). The sampling plan is composed of preestablished sampling strata and transects. These were drawn up according to the specific characteristic of the study area “Mainland France”, or FrM. Description of fields and values of allocation tables: : ( - field name, meaning: value, description of values) region char 5 Study area region_lbl char 50 labelled study area idCampagne (survey) char 15 Name of the campaign programme char 20 Programme name sector char 10 Sampling sector short ID strate char 5 Sampling strata short ID strate_lbl char 15 Labelled sampling strata areaKM double Strata surface area transect_name char 10 transect sampling length_km double Transect length start_x double Coordinates of the start of transect x in decimal degree start_y double Coordinates of the start of transect y in decimal degree end_x double Coordinates of the end of transect x in decimal degree end_y double Coordinates of the end of transect y in decimal degree

As part of the implementation of the monitoring programme of the Marine Strategy Framework Directive (MSFD), the monitoring of demersal fish and cephalopods in coastal soft environments was deemed a priority. Annual observation campaigns of coastal nurseries on soft bottoms were carried out by the Laboratoire Halieutique Méditerranée of the Ifremer station in Sète. The objectives of these campaigns are 1. To evaluate the density, biomass and distribution of fish and cephalopods by trawling, in particular benthic and demersal juveniles (red mullet, gurnard). To do this, around one hundred standardised trawl surveys were carried out over the entire coastal strip of the Gulf of Lion situated between 5m and 40m depth. 2. To systematically measure the size of the individuals collected in order to characterise the importance of the nursery function in the areas observed and to better understand the population dynamics of local species. 3. To gain a better understanding of the coastal zone ecosystem by systematically identifying all the species encountered (including benthic and pelagic invertebrates other than fish and cephalopods), the macro-waste observed and by characterising their hydrological habitats (CTD, oxygen, fluorescence, pH, turbidity, etc.).

Spatial distribution for nutrients data (silicate, nitrate, nitrite, ammonium and phosphate) for all maritime regions in the English Channel and North Sea, the Celtic Seas and the Bay of Biscay. The temporal extent of the data is from 1930 to 2010, most being between 1974 and 2007 with a peak in 1999.

Since 2008, the Coastal Chemical Contamination Observation Network (ROCCH) has taken over from RNO (French National Observation Network for Quality in Marine Environments), which had existed since 1974. ROCCH aims to meet national, community and international obligations relating to monitoring chemicals in marine environments. It is therefore more of a control network than a heritage network as RNO once was. The backbone of ROCCH is to apply the European Water Framework Directive (WFD) and to meet the obligations set out in OSPAR Conventions and in Barcelona. As the WFD insisted on decentralization, ROCCH has gone from having just one project leader (the Ministry for the Environment) to having many decision-makers (water agencies, DIREN etc.). Chemical analyses are no longer conducted by Ifremer alone, but are attributed to other partners following calls for tender. ROCC also includes the monitoring of chemicals in shellfish production areas for the Food safety agency (DGAL) and the Ministry for Agriculture and Fisheries. Monitoring focuses on the three regulated metals: mercury, lead and cadmium in the given areas. Monitoring of these chemical contaminants is conducted in the three marine matrices: water, biota and sediment. Testing also includes imposex, the biological effect of tributyltin (TBT), as required by the OSPAR convention.

The associated data highlights the sampling programme for the data acquisition campaign of Observation on the Aerial Platform for the SAMM1campaign (Aerial Marine Megafauna Monitoring) conducted by the PELAGIS observatory.

Median of the 90th and 99th percentiles of significant height and significant agitation. From the North Sea to the Mediterranean Sea, at a resolution of 2 minutes.

Occurrence rate by observation number for 100km of effort in each 40km mesh in the French mainland EZE in the winter of 2011/2012 and the summer of 2012. Description of the attribute table: survey : campaign Type: observation type Mesh: mesh size in kilometers _no_maille : mesh number The following fields correspond to the calculation of the occurrence rate for the observation number for 1000km of effort for each species or group of species : - [marsouin] common porpoise - [grdDauph] bottlenose dolphin - [lagenor] White-beaked dolphin - [pttDelph] : common dolphin and Striped dolphin - [globiceph] : Long-finned pilot whale + Risso's dolphin - [cakobab] : Sperm whale+ kogias + Beaked whales - [balenopt] : Fin whale + Minke whale + blue whale - [phoque] seal (grey + harbour)

The statistical analysis used (Principal Component Analysis followed by a classification method) to identify groups common to all months and describe the evolution of these groups during the year. The data used allows for monthly tables showing the selected parameters, calculated over the entire geographic area with a resolution of 0.1 °. This method identifies 10 hydrological landscapes present at various times of the year, and characterized by homogeneous hydrological conditions.

Occurrence data of strandings of marine mammals collected by the correspondents of the National Stranding Network (date, position, species) in metropolitan France in 2014-2020.