Created in 2015, it follows on from the RESCO launched in 2009, and REMORa launched in 1993. In 2015, the structure and operation of the former RESCO network was used to implement planned monitoring of oysters. More specifically, the sentinel batches used by the network, representing 3 age classes (6 months, 18 months of the previous year and 30 months of the previous year) are monitored regularly (frequency: bi-monthly or monthly). throughout the year at 12 national sites (corresponding to former RESCO sites). At each passage, counts are made to assess the mortality rate, and different types of laboratory diagnostic tests will be performed: - initially, the new spat batches (Ifremer Standardized Spats) will undergo specific PCR analyzes to search for potentially present infectious agents (OsHV-1 and Vibrio aestuarianus) but also non-specific analyzes (histology, classical bacteriology) for the possible detection of other pathogenis agents ; - for the detection of emerging diseases, the first dying batches detected for each age group, for each site, will undergo specific laboratory (OsHV-1 and Vibrio aestuarianus PCR) and non-specific (histology) diagnostic tests in order to detect as early as possible emerging diseases in these sentinel batches; - for the detection of exotic diseases, in the absence of a hierarchy of exotic diseases being available for oysters, it was decided to monitor the parasite Mikrocytos mackini because infection with this parasite is regulated at European level, on one of the RESCOII sites (Loix en Ré) previously identified as a site at risk with respect to the introduction of this parasite. In addition to these mortality follow-ups and the laboratory diagnoses, each site is equipped with a probe to allow it to gather environmental parameters (temperature, pressure, salinity) at high frequency. The various results are stored in the Quadrige² database, and are available for the various actors involved. The network is closely linked to a dedicated website which allows the dissemination of objectives, protocols and results, and which will be updated every month. In parallel, newsletters summarizing the results obtained are sent by e-mail every month to the State services.

National network for monitoring the health status of shellfish populations in natural beds or in shellfish growing areas. It performs a regulatory role and a public service activity delegated by the Ministry of Agriculture and Fisheries through the DGAL (General Directorate for Food).

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 French national network (REMI) includes a regular monitoring system and a warning system: - The regular monitoring system checks that the level of microbiological contamination in each production area remains within the limits set by the classification defined in the prefectural decree and tests unusual occurrences of contamination. - The warning system is triggered when results of the monotoring programme exceed or are at risk of exceeding the norms defining the quality classes and thresholds, or in case of contamination risk (pollution spillage, storms, etc.), or even in the case of a suspected or confirmed epidemic in shellfish.

REPHY is a national network covering the coast of the French mainland along with that of three of its overseas departments: Martinique, Guadeloupe and Reunion Island. The aims are as follows: - to observe all phytoplankton species in the coastal waters and to monitor events such as coloured water, exceptional blooms, and the proliferation of species which are toxic or disruptive to marine fauna, - Particularly to monitor species producing toxins which are dangerous to shellfish consumers . These objectives are complementary, as the regular monitoring of all phytoplankton species makes it possible to detect known toxic and invasive species, but also to detect potentially toxic species. It is the presence of these toxic species in the water which triggers the monitoring of toxins in shellfish. The mission of REPHY is to monitor shellfish in their natural environment (such as parks and deposits). For shellfish removed from marine environments (that is to say in shellfish logistics establishments or on markets prior to export), national monitoring and control plans are organised by the General Food Directive at the French Ministry of Agriculture. Analyses are performed by the accredited departmental veterinary laboratories as organised by the National Reference Laboratory from the French Food Safety Agency.

The definitive coastal information system, Quadrige stores coastal observation and monitoring network data. In order to manage coastal monitoring data, Ifremer developed the Quadrige² information system. Quadrige is one element of the Water Information System (SIE) http:// www.eaufrance.fr, et à ce titre, contribue aux travaux du Secrétariat d'Administration National des Données Relatives à l'Eau (SANDRE) http://www.sandre.eaufrance.fr. Quadrige Marine Zones is a reference source unique to the Quadrige system. It is used to break down the coast of the French mainland and overseas territories into large areas and to connect each one with observation and monitoring locations.