RESCO REMORA Database : National monitoring network of mortality and growth rates of the sentinel oyster Crassostrea gigas
|Temporal extent||1993 -2021|
|Author(s)||Fleury Elodie1, Normand Julien2, Lamoureux Alice3, Bouget Jean-Francois4, Lupo Coralie5, Cochennec-Laureau Nathalie4, Petton Sebastien1, Petton Bruno1, Pouvreau Stephane1|
Robert Stephane, Mary Charlotte, Pénot Julia, Chevé Julien, Le Gal Dominique, Lebrun Luc, Palvadeau Hubert, Grizon James, Seugnet Jean-Luc, Pépin Jean-Francois, Geairon Philippe, D'Amico Florence, Maurer Daniele, Le Gall Patrik, Mortreux Serge, Quéau Isabelle, Le Roy Valerian, Durand Gaetane, Provost Charlotte, Louis Wilfried, Pien Sébastien, Auby Isabelle, Claude Serge, Hitier Benoist, Langlade Aime, Parrad Sophie, Talarmain Eric, Annezo Jean-Pierre, Chabirand Jean-Michel, Martin Anais, Fleury Pierre-Gildas, Bédier Edouard, Martin Anne-Genevieve
|Affiliation(s)||1 : Ifremer, Laboratoire Physiologie des Invertébrés UMR 6539 LEMAR, ZI de la pointe du Diable, 29280 Plouzané, France
2 : Ifremer, Laboratoire Environnement Ressources Normandie, Avenue du Général de Gaulle, 14520 Port-en-Bessin
3 : Ifremer, Service Valorisation de l'Information pour la Gestion Intégrée et la Surveillance, Rue de l'Île d'Yeu, 44980 Nantes
4 : Ifremer, Laboratoire Environnement Ressources Morbihan Pays de Loire, 12 rue des Résistants, 56470 La Trinité sur mer
5 : Ifremer, Laboratoire de Génétique et Pathologie des Mollusques Marins, Station de La Tremblade, 17390 La Tremblade
The REMORA network carried out by IFREMER was a national network designed to survey the farming performances of the Pacific oyster Crassostrea gigas. From 1993 to 2009 (creation of the RESCO network from this year on), the REMORA network monitored yearly mortality and growth of standardized batches of 18 months-old oysters. From 1995 onward, monitoring of 6 months-old spat oysters farming performances were integrated into the REMORA network. In order to compare data in time and space for these two age classes, sentinel batches of oyster were selected according to a set of origin and size criteria. These sentinel batches were distributed simultaneously every year on the different network sites (in March), and were monitored on a quarterly basis. Over 16 years, 43 sites were followed. These sites were spread over the main French oyster farming areas and provided a national coverage of the multi-year evolution of oyster culture performances. Most of the sites were located on the foreshore at a comparable immersion levels. The REMORA network is a key complementary element in the framework of environmental IFREMER monitoring networks (REPHY, REMI, ROCCH). Field studies were carried out by “Laboratoires Environnement Ressources” (LERs) for the sites included in their geographical area of investigation. These unique national datasets relative to the mortality and growth of two oyster age classes address important questioning regarding the spatiotemporal evolution of oyster performances.
Since 2009, the RESCO network has been monitoring sentinel batches of the cupped oyster Crassostrea gigas in different areas selected among the REMORA network. This monitoring allows the acquisition of a nationally-spread dataset on mortality and growth, to investigate and contribute to the understanding of the spatio-temporal dynamics of the breeding performances of this species. To this end, sentinel batches of oysters corresponding to different origins (wild or hatchery, diploid or triploid) and to two rearing age classes (spats or 18 months-old adults) are deployed simultaneously in 13 sites covering the main shellfish growing regions of the French coastline. Growth and mortality are monitored every fifteen days along with data associated with the presence of infectious agents in sentinel oysters. Environmental variables (temperature, salinity) are also collected. RESCO network's actions thus contribute to disentangle the biotic and abiotic parameters involved in mortality phenomena, by implementing a proactive and integrative approach, accounting for the different compartments (environment / host / infectious agents) likely to interact with the evolution of the oysters’ farming performances.
Geographical location of the RESCO II network workshop sites
The RESCO is a network build from field observations, and the data collected are designed for both scientific applications and management assistance for state stakeholders. Integration of both environmental and physiological markers contribute to the RESCO network specifics, and provide a primary contribution in the research developed to understand oysters mortality events. It also demonstrates that time-series are key elements to further link environmental changes and occurrences of enzootic diseases.