Redfish (Sebastes spp.) Welfare in Cold-Water Aquaculture

Key Facts

• Redfish are viviparous — females give birth to live larvae rather than laying eggs
• They are exceptionally long-lived: some species exceed 100 years in the wild
• Redfish are pressure-sensitive, suffering barotrauma when brought to the surface in capture fisheries
• Their slow growth rate (20-30 years to market size) makes economic aquaculture development extremely challenging
• Pre-slaughter welfare in pilot aquaculture operations uses percussive stunning as the standard method

Welfare Considerations

Redfish welfare in the context of capture fisheries is dominated by barotrauma — the rapid pressure change when fish are brought from depth causes swim bladder rupture, gas emboli, and internal hemorrhage. Most captured redfish die from barotrauma regardless of discarding or retention. In emerging aquaculture contexts, their longevity and slow growth raise questions about the welfare of maintaining fish for decades in farming conditions. The precautionary principle suggests that species with very long natural lifespans and highly specific environmental requirements may face inherent welfare challenges in captivity that require thorough assessment before commercial development.

What You Can Do

• Support deep-sea fisheries reform that reduces incidental capture of redfish and barotrauma mortality
• Advocate for welfare impact assessments before commercial development of redfish aquaculture
• Support research into pressure-equalizing techniques for deep-sea fish bycatch release
• Choose sustainably certified cold-water seafood products from well-managed fisheries
• Engage with Norwegian and Icelandic fisheries welfare research into cold-water species welfare