European sea bass (Dicentrarchus labrax) is a premium aquaculture species farmed extensively across the Mediterranean. Their welfare needs in intensive systems are increasingly recognized by researchers and regulators.
European sea bass welfare in aquaculture is compromised at multiple production stages. Net-pen crowding prevents natural swimming behaviors, causes chronic stress, and increases disease susceptibility requiring antibiotic treatment. Handling during grading and transfer causes significant short-term stress measurable via cortisol elevation. Parasite loads — particularly sea lice in Mediterranean conditions — cause chronic irritation and immune stress. Slaughter practices vary widely: CO2 narcosis is used to sedate fish before killing, but the concentration and exposure time affect how effective it is at minimizing suffering. Percussive stunning followed by rapid bleeding is more humane but rarely implemented at scale. Aquaculture certification schemes including the Aquaculture Stewardship Council are beginning to incorporate welfare criteria for finfish.