Mussel production in relation to ecohydraulic conditions in the culture area of NW Thessaloniki Gulf (NW Aegean, Greece)

Abstract

Culture with longlines system takes place since 1990 with an average production of 10.000 t/year, in NW Thessaloniki Gulf (NW Aegean Sea). This harvest represents the 30 % of the greek annual production. The quality of the mussels is strongly affected by environmental parameters, food availability and culture practices. This study focuses on the mussel production in the NW Thessaloniki Gulf using hydrodynamic data, in relation to food availability, in terms of Chlorophyll-a (Chl-a) records, during the period of January 2006-March 2007. Fig. 1. Study area. The modified aerophotograph is from NCMR (2001). For the purpose of this study, three stations (M1, M2, M3) with longline mussel units and one reference station (M4) with no mussels were frequently monitored (Fig.1). The quality of the mussels was expressed as condition index, wet weight (Davenport & Chen, 1987) (commercial weights) while the distance between socks were measured. Hydrodynamic results were based on field measurements in combination with a mathematical model as described by Savvidis et al. (2007). Food availability in terms of chl-a was measured using standard methods. As culture operation, the distance between the socks was measured in the three stations M1,M2 M3. The qualitative evaluation of mussel cultures handling, their environment and the mussel production was based on socks distance, area hydrodynamics, Chl-a, mussel wet weights and condition index %.