Stocking density in salmon farming directly affects welfare outcomes. Higher densities increase stress, disease risk, and aggression, making density management a central welfare challenge.
Stocking density is one of the most directly manageable welfare variables in salmon aquaculture. The evidence that crowding impairs welfare is robust, and the mechanisms — increased aggression, oxygen competition, disease transmission, and stress — are well understood. The welfare case for lower stocking densities is strong, and voluntary higher welfare certifications consistently require lower maxima than legal standards. Consumer demand for certified lower-density salmon drives market-based welfare improvement.