Fish are sentient beings capable of experiencing pain and distress (Lambert et al. 2022), yet the European Union (EU) currently lacks a practical, standardised set of welfare indicators for the approximately 640 million fish slaughtered annually (Mood et al., 2023). Current legislative frameworks often rely on outdated input-based standards that fail to reflect recent scientific advancements. This presentation draws on a recently published report (Eurogroup for Animals, 2026), which proposes three core policy indicators designed to be measurable, auditable, and applicable across major production systems to support regulatory compliance and funding conditionality.
Proposed Indicators
The framework identifies three priority indicators to capture acute risk, chronic compromise, and retrospective system-level failure:
Dissolved Oxygen (DO) Stability (Resource-based Indicator): DO is a critical preventative indicator. Maintaining stability enables proactive risk reduction before the onset of suffering. A minimum concentration of 70% is considered essential for farmed fish welfare.
External Injuries and Fin Damage (Animal-based Indicator): These provide a cumulative record of suboptimal environmental and husbandry conditions. Scoring can be integrated into existing post-slaughter inspection protocols under Regulation (EU) 2017/625 to minimise additional handling stress.
Mortality (Animal-based Indicator): Mortality serves as a retrospective signal of severe welfare breakdown. Standardising mortality data across the EU would allow for benchmarking and the identification of systemic risks.
Policy Relevance and Discussion
These indicators align with key EU instruments, including the Strategic Aquaculture Guidelines (SAG), the Common Fisheries Policy (CFP), and the European Maritime, Fisheries and Aquaculture Fund (EMFAF). By moving beyond mere input-based requirements toward outcome-based assessment, this framework provides a transparent mechanism for monitoring and enforcement. Just as the modernisation of terrestrial welfare rules strengthens the resilience of EU agriculture, establishing specific, science-based rules for aquatic animals is a strategic investment in the sustainability and fairness of the aquaculture sector. Future directions should also integrate automated behavioural monitoring, such as respiratory and swimming patterns, as these technologies become commercially viable, as they provide direct, outcome-based indicators of fish welfare.
Acknowledgment
This work was supported by Eurogroup for Animals.
References
Arechavala L��pez, P., Bassett, D., Llorente Manzanares, M., Pacchiarini, T. and Xandri Royo, P.M. (2025) Code of Good Practices on Fish Welfare and Fish Welfare Indicators: Implementing the Strategic Guidelines for EU Aquaculture. Publications Office of the European Union. https://doi.org/10.2926/4420264
Eurogroup for Animals (2026) Policy Welfare Indicators for Fish Welfare in European Aquaculture. Eurogroup for Animals Policy Brief. Brussels, Belgium. https://www.eurogroupforanimals.org/library/policy-indicators-fish-welfare-european-aquaculture
Lambert, H., Cornish, A., Elwin, A. and D'Cruze, N. (2022) A Kettle of Fish: A Review of the Scientific Literature for Evidence of Fish Sentience. Animals. 12 (9) 1-13. https://doi.org/10.3390/ani12091182
Mood, A., Lara, E., Boyland, N.K. and Brooke, P. (2023) Estimating global numbers of farmed fishes killed for food annually from 1990 to 2019. Animal Welfare. 32 e12. https://doi.org/10.1017/awf.2023.4
Noble, C., Abbink, W., Alvestad, R. et al. (2026) Welfare Indicators for Aquaculture Research: Toolboxes for Five Farmed European Fish Species. Reviews in Aquaculture. 18 (1) e70109. https://doi.org/10.1111/raq.70109