Salmon Sea Cage Welfare: Net Integrity and Environment

Sea cage integrity, fouling, and environmental factors significantly affect salmon welfare in open-water aquaculture - management and technology improvements reduce welfare risks.

Key Facts

Net fouling by algae and biofouling organisms reduces water flow and oxygenation in sea cages
Predator nets and anti-seal measures affect seal welfare if incorrectly designed or maintained
Strong current events can damage net integrity, causing mass escape events with welfare implications for escaped fish
Mooring failure in storms has caused large-scale salmon mortality events with severe welfare consequences
Remote monitoring of net integrity and environmental conditions reduces response time to welfare events

Welfare Considerations

Sea cage environmental management affects salmon welfare through multiple pathways. Net fouling reduces the oxygen availability that salmon require for normal physiology. Predator net failures allow seal entry causing injury and panic. Storm damage can cause net collapse with catastrophic welfare consequences. Regular net cleaning, predator exclusion that protects both salmon and seals, storm-ready moorings, and remote environmental monitoring all contribute to welfare maintenance. Investment in sea cage infrastructure quality is directly reflected in fish welfare outcomes.

What You Can Do

Support aquaculture producers with documented sea cage maintenance and monitoring programmes
Advocate for sea cage integrity standards to be part of aquaculture welfare certification
Learn about the environmental factors affecting salmon welfare in sea cage systems
Choose salmon from producers with strong environmental and infrastructure management