European Eel Welfare in Aquaculture and Fisheries

Key Welfare Considerations

• The European eel has declined by over 95% in three decades — critically endangered status creates welfare and conservation urgency.
• Complex life history including oceanic spawning migration means eel welfare is affected across multiple geographies.
• Glass eel stage welfare: juvenile eels are collected from estuaries and stocked into aquaculture systems.
• Glass eel collection welfare requires careful handling — eels are fragile and prone to slime loss stress.
• Water temperature management is critical for eel welfare — optimal range is 20-25°C for growth.
• Eel farming uses intensive RAS systems requiring careful water quality management for welfare.
• Stocking density significantly affects eel welfare through competition, oxygen depletion, and disease risk.
• Edwardsiellosis bacterial disease causes significant welfare mortality in farmed eel populations.
• Eel herpesvirus (AngHV-1) causes welfare disease requiring quarantine protocols at eel farms.
• Pre-slaughter welfare for eels is challenging — electrical stunning requires calibration for this elongated species.
• Wild eel capture including fyke netting requires rapid welfare processing to prevent prolonged distress.
• Eel ladders and bypass channels provide welfare-supporting migration routes at barriers.
• Catch-and-release eel angling requires careful welfare handling — eels tolerate air exposure poorly.
• Restocking programmes using farm-raised eels support wild population welfare recovery.
• Sustainable eel aquaculture and fisheries management are inseparable welfare and conservation priorities.