Gilthead Sea Bream Welfare: Mediterranean Aquaculture

Key Welfare Considerations

• Gilthead sea bream aquaculture produces approximately 200,000 tonnes annually across Mediterranean countries.
• Optimal welfare temperature for sea bream is 22-26°C — cold stress below 12°C causes welfare mortality.
• Sea bream are euryhaline — welfare tolerance of salinity variation is high but welfare optimum is full seawater.
• Parasitic disease including Sparicotyle chrysophrii gill monogenean causes welfare respiratory distress.
• Myxozoan parasites cause welfare mortality in both larval and juvenile production stages.
• Stocking density above 25-30kg/m³ causes welfare aggression, fin damage, and chronic stress.
• Vaccination against pasteurellosis and vibriosis reduces antibiotic use and welfare disease burden.
• Sea lice welfare challenges are lower in sea bream than salmon but still require management.
• Crowding for treatment procedures causes significant welfare cortisol stress — handling minimisation is welfare-positive.
• Pre-slaughter welfare — crowding, transport, and CO2 or electric stunning — requires standardisation.
• Welfare indicators for sea bream include fin erosion, cataracts, and skin wound prevalence.
• Behavioural welfare assessment through feeding motivation and social interaction monitoring is developing.
• ASC (Aquaculture Stewardship Council) developing sea bream welfare criteria through stakeholder consultation.
• Mediterranean sea bream aquaculture welfare is improving through producer welfare commitment programmes.
• Consumer demand for welfare-certified Mediterranean fish products is emerging — standards need development.