MISOLRE
| Type | Oceanographic cruise |
|---|---|
| Ship | Gwen Drez |
| Ship owner | Ifremer |
| Dates | 04/09/2003 - 26/09/2003 |
| Chief scientist(s) | DESAUNAY Yves |
ÉCOLOGIE ET MODÈLES POUR L'HALIEUTIQUE Centre Ifremer de Nantes Rue de l'Ile d'Yeu BP 2105 44311 Nantes Cedex 3 +33 (0)2 40 37 41 67 |
|
| DOI | 10.17600/3050120 |
| Objective | Monitoring the Bay of Vilaine nursery (series begun in 1981): distribution and epibenthic population, relation to the extent of the winter-spring river plume and hydrological conditions. Validating ecological indicators of nursery quality (sole, group 0 and associated community) and aiming for optimization for use in a monitoring network on the scale of the Bay of Biscay. Test on a "new" site, the northern sector of Arcachon. Sampling of sole juveniles from group 2 (before their first migration to areas where the adults are) to establish their microchemical signature which can be linked to sampling to be carried out during the following breeding season (first quarter 2004, cruise to be planned) on spawning grounds. Coastal nurseries were explored between depths of 5 meters (the Gwen-Drez vessel's limit for access) and depths of 25 meters (outer edge of the nurseries). Standardized samples were made using beam trawling (CP3M, 3 meter wide trawl, 10 mm mesh size, lasting 15 minutes); the biological samples required trawling with larger gears (CV, 25 m Vendéen-type trawl with a double heaving bag, with 10 or 20 mm mesh, lasting 30 to 45 minutes). Beam trawling hauls were processed using the standard protocol (Desaunay and Guérault protocol manual, 2002). All sampled species were identified and counted and all fish of interest to fisheries were measured. As for sole, 708 pairs of otholiths were taken to determine the annual classes and over 600 individuals kept for microchemical analyses. Hydrology measurements (temperature and salinity) were noted. This falls under the PNEC project, Bay of Biscay worksite in the Bay of Biscay challenge. |
