Fish Net Pen Welfare | Animal Welfare Hub

How net pen aquaculture affects fish welfare and what improvements are being made.

Key Facts

Net pen aquaculture confines fish in floating cages in open water, typically coastal or fjord environments
Stocking density in net pens significantly affects fish behaviour, injury rates, and stress responses
Water flow through net pens is critical for oxygen supply and waste removal
Net pen systems are vulnerable to weather, predator attack, and disease spread from wild fish populations
Closed containment systems eliminate many net pen welfare problems but have higher cost and energy requirements
Welfare research specific to net pen conditions has grown significantly in recent years

Welfare Considerations

Net pen aquaculture is the dominant production system for Atlantic salmon and sea bass globally, and its welfare characteristics have received increasing scientific and regulatory scrutiny. The stocking density, environmental conditions, sea lice management, and slaughter practices within net pen systems all significantly affect fish welfare. Improvements within net pen systems — lower densities, better lice management, improved handling protocols — can meaningfully reduce welfare burden. Closed containment systems that eliminate several net pen welfare problems remain expensive but represent a direction of development that may become mainstream as technology matures.

What You Can Do

Support net pen certification schemes that set minimum stocking density and welfare management standards
Advocate for regulatory adoption of welfare-based stocking density limits for net pen aquaculture
Engage with retailers about the welfare requirements they apply to net pen farmed fish suppliers
Support research into closed containment as a welfare-superior alternative to traditional net pens
Choose certified farmed fish from operations with documented welfare monitoring and management protocols