Developing reliable welfare metrics for farmed fish is essential for assessment, certification, and improvement. The science of fish welfare measurement is advancing rapidly.
The development of robust welfare metrics for fish is foundational to all other welfare improvement in aquaculture. Without reliable ways to measure welfare, it is impossible to assess the impact of husbandry changes, verify certification claims, or monitor compliance with welfare standards. The challenge is that fish welfare indicators are less well validated than those for mammals and require species-specific calibration. Additionally, the scale of aquaculture — millions of fish per production cycle — demands metrics that can be assessed practically in commercial settings, not just under research conditions. Progress in developing and validating fish welfare metrics enables the entire ecosystem of certification, regulation, and industry improvement that depends on measurable standards.