Chile, Norway and Scotland Show Three Paths to Fish Welfare Law

Farmed salmon now dominate global aquaculture, and the three jurisdictions that produce most of them regulate fish welfare in strikingly different ways. A narrative review published in Frontiers in Veterinary Science compares Chile, Norway and Scotland, which together account for roughly 90 percent of global farmed Atlantic salmon production, with Norway and Chile alone contributing about 83 percent and Scotland around 7 percent. The author, Juan Antonio Valdés of Universidad Andres Bello in Chile, argues that the real question is not which country has the most welfare legislation, but how far each has translated broad legal principles into measurable, enforceable requirements.

The review distinguishes between two dimensions that are often conflated: regulatory operationalization and regulatory effectiveness. Operationalization describes the extent to which legal welfare obligations are converted into scientifically supported indicators, standardized monitoring, intervention thresholds, corrective actions, oversight and periodic scientific review. Effectiveness, by contrast, can only be demonstrated through independent evaluation of measurable welfare outcomes on farms. The author stresses that differences in how detailed a regulatory system is should never be read as evidence that fish are better or worse off, a caution that runs through the entire comparison.

Chile, the world’s second-largest farmed salmon producer, combines explicit legal recognition of fish welfare with an extensive sanitary and environmental regulatory architecture. The General Fisheries and Aquaculture Law includes Article 13F, which states that aquaculture must safeguard animal welfare and avoid unnecessary suffering, while Article 32B of the disease-control regulation RESA requires fish to be sedated or rendered insensible before gill cutting. However, these provisions do not define fish welfare or establish a standardized framework of animal-based measures through which welfare can be systematically assessed at farm level. Even the stunning requirement remains procedure-based, with no standardized animal-based criteria for verifying that fish are effectively stunned and remain unconscious until death.

What Chile’s system does generate is a large volume of data potentially relevant to welfare, including mortality, disease occurrence, stocking density, sanitary treatments, animal movements and environmental conditions. The review notes that this information is currently interpreted within sanitary, environmental, epidemiological or production-control frameworks rather than integrated into a national welfare-assessment system. The principal gap, therefore, is not the absence of regulation but the limited incorporation of standardized animal-based measures, welfare-specific intervention criteria and outcome-based verification into the regulatory framework itself.

Norway represents the opposite pole: direct incorporation of detailed welfare requirements into aquaculture operational regulation. The Animal Welfare Act of 2009 explicitly includes fish, recognizes the intrinsic value of animals independently of their utility, and establishes a positive duty of care covering environmental conditions, feeding, supervision and preventive management. The Aquaculture Operation Regulations translate these principles into farm-level requirements on competence and training, contingency planning, facility design, water quality, stocking density, feeding and fasting, vaccination, crowding, pumping, handling, mortality, health inspections, slaughter and record keeping. Transport is separately regulated, and complementary instruments address disease prevention, biosecurity, salmon lice and environmental risks, including the national traffic-light system for production.

Norway has also embedded science-based assessment into farm management. The FISHWELL project developed operational welfare indicators and laboratory welfare indicators for salmonids, contributing to the LAKSVEL protocol for standardized welfare surveillance of Atlantic salmon in marine net pens. Indicators such as mortality, external injuries, fin condition, behavior, feeding activity and environmental parameters provide a standardized basis for welfare-risk assessment. Yet the review is careful to add caveats: the biological validation of individual indicators and thresholds may vary with species, life stage and production context, and the availability of scoring systems should not be taken as evidence that every indicator or severity category has been equally validated against underlying physiological welfare states.

Crucially, the review does not present Norway as a finished success. Recurrent welfare concerns associated with mortality, crowding, pumping, delousing, handling, transport and slaughter demonstrate that detailed regulation and sophisticated assessment tools do not necessarily translate into consistently improved welfare outcomes in practice. Norway illustrates extensive operationalization, but the effectiveness of those mechanisms must still be evaluated independently through measurable outcomes, and challenges remain in formally incorporating animal-based results into regulatory decision-making.

Scotland occupies a middle position that the author characterizes as a distributed governance model. The Animal Health and Welfare (Scotland) Act 2006 establishes a general duty of care that covers farmed fish, but there is no dedicated statutory welfare code for farmed salmon. Transport is governed by the Welfare of Animals (Transport) (Scotland) Regulations 2006, slaughter by the Welfare of Animals at the Time of Killing (Scotland) Regulations 2012 and Council Regulation (EC) No. 1099/2009, supported since 2025 by Scottish Government guidance on welfare during salmon slaughter. Aquaculture and Fisheries Acts from 2007 and 2013 and the Aquatic Animal Health (Scotland) Regulations 2009 regulate disease, parasite management, biosecurity, containment and farm practices, while the Aquaculture Code of Practice and the industry Code of Good Practice translate expectations into practical guidance. Scotland also participated in FISHWELL, and its Vision for Sustainable Aquaculture identifies improved health and welfare and reduced cumulative mortality as strategic priorities, though these policy objectives do not themselves create legally binding animal-based thresholds.

The comparison’s central limitation is data harmonization. Mortality, disease occurrence, injuries, treatment-related losses and behavioral alterations are not necessarily defined, measured or publicly reported using equivalent methodologies across the three jurisdictions, so differences in regulatory design cannot be assumed to correspond to differences in welfare performance. The review’s answer to this shared challenge is a proposed framework called Evidence-Based Welfare Regulation, or EBWR. It connects legal welfare objectives with evidence-qualified resource-, management- and animal-based indicators, standardized monitoring, context-specific thresholds or reference ranges, predefined corrective actions, outcome verification, regulatory accountability and periodic scientific review. The author emphasizes that EBWR is not a new welfare-assessment methodology; its components already exist in welfare science and aquaculture. The contribution lies in integrating them within an adaptive regulatory feedback system in which legislation defines objectives, science supplies indicators and reference values, producers monitor risks, and authorities verify both compliance and outcomes.

For Chile, the proposed pathway builds on existing institutional capacity rather than creating a parallel system. It would begin with a scientifically grounded regulatory definition of welfare as the physical and mental state of an animal in relation to its living and dying conditions, followed by species- and production-stage-specific standards for the main farmed salmonids, standardized assessment protocols using evidence-qualified operational welfare indicators during routine farming and high-risk procedures such as handling, crowding, grading, vaccination, transport and slaughter, and finally linkage of welfare outcomes to regulatory oversight, verification and periodic scientific review. Thresholds, the review argues, should rarely be universal fixed numbers; their biological relevance depends on species, life stage, health status, exposure intensity, duration, recovery time and interactions among simultaneous stressors, so scientifically supported reference ranges or tiered warning, corrective and critical thresholds may often be more appropriate than single limits. The review also looks forward: climate change is likely to raise welfare risks through warming waters, marine heatwaves, reduced oxygen and shifting pathogen distributions, while precision aquaculture technologies such as computer vision, biosensors and machine learning may enable earlier detection of welfare deterioration, provided their outputs are biologically validated and tied to clear decision rules. Ultimately, the author concludes, a welfare regulatory system should be judged not by the number of its provisions but by its capacity to detect risks, trigger proportionate interventions, verify their effectiveness through measurable outcomes and adapt as evidence evolves.

Subject of Research: Comparative regulation of farmed fish welfare in Chile, Norway and Scotland and a proposed evidence-based regulatory framework

Article Title: Toward evidence-based fish welfare regulation: policy lessons from Chile, Norway, and Scotland

Article References: Valdés, J. A. (2026). Toward evidence-based fish welfare regulation: policy lessons from Chile, Norway, and Scotland. Frontiers in Veterinary Science, 13, Article 1972966. https://doi.org/10.3389/fvets.2026.1972966

Image Credits: AI Generated

DOI: 10.3389/fvets.2026.1972966

Keywords: fish welfare, aquaculture, salmon farming, Chile, Norway, Scotland, animal welfare regulation, operational welfare indicators, animal-based measures, evidence-based regulation, Frontiers in Veterinary Science, policy comparison