Grey Mullet Welfare in Coastal and Estuarine Aquaculture

Key Facts

• Grey mullet are euryhaline detritivores tolerating wide salinity and temperature ranges
• They feed by filtering organic particles and biofilm from sediment — difficult to replicate with commercial pellets
• Mullet are farmed extensively in coastal lagoons and ponds where they feed naturally on organic matter
• Extensive systems have lower welfare costs per fish but provide little monitoring or individual welfare management
• Semi-intensive supplementary feeding with appropriate formulations can improve welfare through reliable nutrition

Welfare Considerations

Grey mullet welfare in extensive coastal aquaculture is characterized by relatively natural conditions but lack of monitoring or welfare management. Fish experience natural temperature, salinity, and prey fluctuations. Welfare problems arise during low-oxygen events common in summer (algal blooms, calm conditions), during extreme cold (temperature crashes below 5C cause mass mortality), and at harvest when traditional netting and live-transport methods are used. Semi-intensive operations with supplementary feeding generally have better individual condition but face the same harvest welfare challenges. Pre-harvest welfare improvement is the highest-impact area for this species.

What You Can Do

• Support development of welfare monitoring and slaughter standards for mullet in Mediterranean aquaculture
• Advocate for inclusion of mullet in national aquaculture welfare legislation by regulators
• Source mullet from certified operations with transparent production methods where possible
• Support research into aeration technology for preventing low-oxygen mortality events in extensive ponds
• Engage with Mediterranean aquaculture welfare initiatives targeting traditional extensive systems