Aquaculture

Farmed Salmon Hatchery Crowding Welfare

Atlantic salmon fry and parr reared in hatcheries experience crowding conditions that affect their early development and post-release welfare.

Key Facts

Hatchery salmon are reared at densities far exceeding natural stream conditions
High density causes aggression, fin damage, and reduced growth in subordinate fish
Early social experience shapes aggression behaviour in farmed and released salmon
Water quality deteriorates quickly at high densities
Some supplementation programmes use hatchery fish to boost wild salmon populations

Welfare Considerations

Hatchery salmon reared at high densities develop aggressive behavioural tendencies and show fin damage from conflict. This early welfare deficit shapes their fitness for subsequent sea-cage or wild environments. Reducing hatchery density and providing appropriate environmental enrichment improves both welfare and production outcomes.

What You Can Do

Support aquaculture standards specifying hatchery stocking density limits
Advocate for enriched hatchery rearing environments for salmon
Choose salmon products from producers with transparent hatchery welfare standards