Regional monitoring network of the Blue mussel (Mytilus edulis) rearing performances in the Pertuis Charentais sounds (Bay of Biscay). REMOULA network 2000 - 2012

On a yearly basis, mussel farming produces around 13 000 metric tons of mussel in the Pertuis Charentais sounds (Pertuis Breton et Pertuis d’Antioche). This represents 23% of the Blue mussel (Mytilus edulis) production along the French Atlantic coastline. Production is characterized in this area by to types of growout systems: the ‘bouchot’ type culture using wooden poles(p) and off-shore longlines(l). Environmental conditions are mainly estuarine. Taking into account those cultural practices, the REMOULA monitoring network has been deployed since 2000 to provide baseline information to better understand the Blue mussel (Aiguillon(p) and Filières Pertuis Breton(l)) or trimester (Roulières(p), Marsilly(p), Yves(p), Boyard-bouchot(p) – completed by the stations Saumonards Filières(l) and Filières Chatellaillon 2(l)  (2008 to 2012).  Between 2000 and 2005 the mussel batches monitoring lasted 12 months whereas it lasted 15 months from 2006 to 2012. The initial batch of mussel is originating from the spat settlement the previous year and calibrated. On the 8 monitoring stations, calibrated mussel batches were deployed into bags (120 mussels/bag). Biometric data are measured during each monthly survey (30 individuals) and a mortality rate estimated. Additional information is obtained through biochemical analysis (proteins, lipids, carbohydrates) on 3 mussel pools of 10 individuals in 2000, 2001, 2002, 2003 and 2004. Moreover gametogenic data are collected on 15 mussels (2003 and 2004). The data storage is organized using the Quadrige2 system and characterized by individual field campaign. Coastal monitoring data  Available parameters : Individual measurement :  length, shell weight, dry meat weight. Width and height at the beginning and the campaign end. Average measurement : individual weight (3x10 individuals), Calculated data: Lawrence & Scott indicator, Walne and Mann indicator, meat indicator, mortality rate % Observations : Pinnotheres and Polydora infestations, parasites. Gametic status : identification of 8 maturation stages (0, 1, 2, 3A1, 3A2, 3B, 3C, 3D) according to Lubet (1959) and Suarez (2005) Biochemical data : analytical protocols - Proteins : Lowry et al (1951) modified Razet et al (1976). Lipids : Marsh and Weinstein (1966). Carbohydrates and Glycogen Dubois et al (1956). The shellfish biochemical proximate composition reviewed by Faury, Geairon, Moal, Pouvreau, Razet, Ropert and Soletchnik (2003).