Growth performance of mussel recruits on raft culture after Prestige oil spill Laura G. Peteiro, José MF Babarro, Uxío Labarta & María José Fernández Reiriz Instituto de Investigaciones Marinas CSIC, Vigo Spain Phone: Fax:

From ENVISAT ASAR satellite on November 17 th, PAH in mussel tissues -Physiological / Biochemical measurements (survival in air, biochemical composition) Mussel characterization at seeding (February 2003) Labarta et al., MEPS 2005 Most affected area

Original locations of mussel populations translated for experimental culture RedesMirandaPindoBueu Length (mm) Total DW (g) Length (mm) Total DW (g) Length (mm) Total DW (g) Length (mm) Total DW (g) Seeding21,4±7.90,3±0.010,4±3.60,1±0.015,6±6.80,2±0.018,0±5.20,2±0.0 Thinning-out50.6± ± ±6.23.2± ±7.52.5± ±7.24.8±0.4 Labarta et al., MEPS 2005 Corporal parameters at seeding and thinning-out

Growth curves in length and total dry weight fitted to Gompertz model P t =P ∞ (e -e (-k*(t-t´)) )

Seeding/Thinning-outThinning-out/Harvest Initial length/weight at seeding and thinning-out had no effect on growth rate (GR) (ANCOVA p>0.05) Pindo showed the lowest weight GR in both phases of the culture (p<0.05) Growth Rates

Seeding/Thinning-outThinning-out/Harvest DW t =DW ∞ (e -e (-k*(t-t´)) ) Pindo DW ∞ (p<0.05) Bueu t´ (p<0.05 ) Growth rates in total dry weight

CI is a weak parameter to determine stress situations: - Nutritional state - Reproductive cycle - Pollution Condition Index evolution along the culture

% indiv≥70mm lowest for Pindo mussels (p<0.05) Yield at harvest

Comparison among mussel populations showed the following remarks: % individuals ≥ 70 mm, lowest values for Pindo mussels Lowest Total DW values at harvest for Pindo mussels A poor commercial classification in pieces/kg - -

- Population from Pindo showed the lowest growth rate values in weight in both phases of the culture. Preliminary Remarks: - The maintenance of lower growth rates along the culture resulted in poorer commercial yield at harvest for Pindo mussels. - The latter growth performance of Pindo mussels would be a sub-lethal effect that might reflect its worse physiological and biochemical conditioning (lipid classes, fatty acids) monitored at the onset of the culture by Labarta et al., (MEPS 2005).