Deep Sea Trawling and Fish Welfare at Depth

Bottom trawling disrupts deep sea ecosystems and catches fish from pressure depths where decompression injury during hauling causes significant welfare harm, raising ethical questions about deep water fishing practices.

Key Facts

Bottom trawling involves dragging weighted nets across the seabed, catching everything in their path and destroying slow-growing deep sea habitats
Fish caught at depth experience rapid decompression during hauling — swim bladder expansion causes internal damage and barotrauma that is painful and often fatal
Deep sea species including orange roughy and Patagonian toothfish are slow-growing and long-lived, making populations vulnerable to rapid depletion
The UN estimates that 26 million square kilometres of seafloor are trawled annually — an area larger than South America
High seas bottom trawling occurs in international waters with minimal regulation, enabling practices prohibited in national waters
Barotrauma causes eyes to protrude, the stomach to evert through the mouth, and internal rupture — clear indicators of significant tissue injury
Deep sea coral communities that take centuries to grow are destroyed in minutes by bottom trawling, eliminating habitat for countless species

Welfare Considerations

Deep sea trawling combines ecological devastation with individual animal welfare harm of significant scale. The barotrauma experienced by fish hauled from depth represents genuine suffering across billions of individuals annually, occurring in one of the least regulated areas of global food production. The combination of ecosystem destruction and individual welfare harm makes deep sea trawling one of the most ethically problematic food production practices currently in widespread use. Consumer avoidance of deep sea species subject to trawling, combined with advocacy for high seas fishing regulation through international bodies, represents the most accessible individual contribution to addressing this welfare and conservation crisis.

What You Can Do

Avoid seafood from deep sea species commonly caught by bottom trawling including orange roughy and deep-water shrimp
Support campaigns for international high seas bottom trawling bans through donations to ocean conservation organisations
Engage supermarkets about their deep sea species sourcing and bottom trawling policies
Advocate for your government to support international agreement on high seas marine protection
Choose seafood certified by credible sustainability schemes that exclude bottom-trawled deep sea species
Support research into less harmful fishing methods that can replace bottom trawling for target species
Share information about deep sea trawling ecological and welfare impacts with people engaged in seafood sustainability