Aquatic Animals

Wild Salmon and Net Pen Aquaculture Interactions

Open-net salmon farms create welfare risks for wild salmon populations through sea lice transmission, escape events, and competition, raising ethical questions about the co-existence of wild and farmed species.

Key Facts

Sea lice from Atlantic salmon farms can devastate juvenile wild Pacific salmon passing nearby
Escaped farmed salmon interbreed with wild populations, reducing genetic diversity and fitness
Net pen waste affects benthic ecosystems beneath and around aquaculture sites
Closed containment systems eliminate most wild salmon interaction risks but cost more to operate
Several regions have imposed siting restrictions or bans on net pen salmon farms near wild migration routes

Welfare Considerations

Net pen salmon aquaculture creates welfare externalities for wild fish populations that are often invisible in farm welfare assessments focused solely on farmed animals. Wild juvenile salmon navigating sea lice plumes from farms experience significant parasite burdens affecting their survival and welfare. Supporting closed containment aquaculture and responsible siting regulations protects both wild fish welfare and ecosystem health.

What You Can Do

Choose salmon from land-based closed containment farms when available
Advocate for siting regulations that keep net pen farms away from wild salmon migration routes
Support research and transition funding for closed containment aquaculture systems
Learn about wild salmon ecology and the impacts of aquaculture siting in your region