Salmon Cleaner Fish Welfare: Wrasse and Lumpfish Care Standards

Wrasse and lumpfish used as cleaner fish in salmon farms have their own welfare needs that are frequently overlooked in the focus on salmon welfare.

Key Facts

Ballan wrasse, corkwing wrasse, and lumpfish are the primary cleaner fish species used in Norwegian and Scottish salmon farming
Wrasse mortality rates in salmon pens are high — averaging 30-60% annually in some operations
Wrasse require specific habitat features including hiding structures and appropriate temperature ranges
Wrasse are temperate species that experience heat stress in surface waters during summer warm events
Lumpfish are more temperature-tolerant but require higher stocking densities than recommended to achieve louse reduction

Welfare Considerations

Cleaner fish welfare has historically been neglected in the focus on salmon welfare improvement. However, deploying hundreds of millions of wrasse and lumpfish into salmon pens with inadequate welfare management is itself a significant welfare issue. Wrasse require hiding structures to avoid harassment from salmon, access to supplementary feed, and monitoring of population health indicators including survival rates and injury occurrence. Lumpfish welfare requires attention to their schooling behavior and social needs. Industry recognition of cleaner fish as welfare-significant animals with their own welfare requirements is growing but implementation of standards remains inconsistent.

What You Can Do

Support development of cleaner fish-specific welfare standards as a component of salmon certification
Advocate for mandatory cleaner fish mortality rate reporting as a welfare transparency requirement
Engage salmon farming companies about their cleaner fish welfare policies and management practices
Support research into alternative biological and non-biological lice control that reduces cleaner fish dependence
Choose ASC-certified salmon that includes some cleaner fish welfare-relevant audit requirements