TOWARDS STANDARDISED FISH WELFARE ASSESSMENT: DEVELOPMENT OF A DIGITAL MULTI-INDICATOR PLATFORM

Introduction

Fish welfare assessment is increasingly recognized as a key component of modern aquaculture, but its routine implementation remains challenging. Frameworks such as the Salmon Welfare Index Model and FISHWELL have shown the value of formal assessment using operational welfare indicators (Stien et al., 2013; Noble et al., 2018). However, welfare information is often fragmented across production records, health monitoring and isolated observations. Production key performance indicators are relevant to welfare, but they do not fully capture behavioural expression, environmental suitability or management practices (Martins et al., 2012; Saraiva et al., 2019). This work describes the development and preliminary applicability testing of WAAVE - Welfare Assessment of Aquatic Vertebrates, as a digital multi-indicator workflow for structured fish welfare assessment across aquaculture, research laboratories and public aquaria.

Methodological development

WAAVE was developed by FishEthoGroup as a mobile and web-based workflow grounded in scientific literature and applied welfare research. The indicator catalog integrates animal-based, environmental-based and management-based indicators, including external appearance, feeding behaviour, swimming patterns, respiratory rate, aggression, water quality, light conditions, disturbance, staff training, handling protocols, records and traceability. The workflow was designed to assign indicators according to the selected production or rearing context, allowing aquaculture, laboratory and public aquarium assessments to use a consistent structure while retaining setting- and species-specific relevance.

Indicators are evaluated through a traffic-light scoring system and are manually scored by trained users. The workflow then summarizes the assessment into structured outputs, including an overall welfare score, priority concerns and a report intended to support interpretation and follow-up actions (Figure 1). The aim is not to automate welfare judgement, but to standardize indicator selection, scoring and reporting in a transparent format that can be reviewed and improved through validation.

Figure 1. WAAVE workflow from indicator selection to structured welfare output.

Scientific basis and preliminary application

WAAVE reflects work highlighting the importance of species-specific welfare knowledge (Saraiva et al., 2019), behavioural indicators (Martins et al., 2012), environmental enrichment (Arechavala-Lopez et al., 2022), and context-dependent management decisions such as stocking density (Saraiva et al., 2022). The platform has undergone internal applicability testing in FishEthoGroup facilities and preliminary use with Odysseo Oceanarium, Mauritius. These early applications suggest that a structured digital workflow can help identify welfare aspects not routinely captured through production or health monitoring alone. WAAVE is now entering a closed testing phase with selected partners to evaluate usability, indicator relevance, reporting usefulness and setting-specific applicability under operational conditions.

Discussion

WAAVE is intended to complement, not replace, existing farm management and health monitoring systems. Its contribution lies in translating welfare science into a practical, human-scored workflow that integrates behavioural, environmental and management observations. By standardizing data collection and summarizing outputs, WAAVE may support routine welfare monitoring, staff communication and continuous improvement across facilities working with fish. Future work will focus on validation and refinement of setting-specific and species-specific indicator sets.

Acknowledgements

The authors thank all collaborators and partner organizations contributing to WAAVE development, particularly Odysseo Oceanarium for its early collaboration, and the partners involved in the next testing phase. This work was co-funded by the European Union's Horizon Europe Project 101136346 EUPAHW. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Executive Agency. Neither the European Union nor the granting authority can be held responsible for them.

References

Arechavala-Lopez, P., Cabrera-Álvarez, M.J., Maia, C.M., Saraiva, J.L. (2022) Environmental enrichment in fish aquaculture: A review of fundamental and practical aspects. Reviews in Aquaculture. 14(2):704-728. https://doi.org/10.1111/raq.12620

Martins, C.I.M., Galhardo, L., Noble, C., Damsgård, B., Spedicato, M.T., Zupa, W., et al. (2012) Behavioural indicators of welfare in farmed fish. Fish Physiology and Biochemistry. 38:17-41. https://doi.org/10.1007/s10695-011-9518-8

Noble, C., Gismervik, K., Iversen, M.H., Kolarevic, J., Nilsson, J., Stien, L.H., Turnbull, J.F. (Eds.) (2018) Welfare Indicators for farmed Atlantic salmon: tools for assessing fish welfare. Nofima, Tromsø, Norway. 351 pp.

Saraiva, J.L., Arechavala-Lopez, P., Castanheira, M.F., Volstorf, J., Studer, B.H. (2019) A Global Assessment of Welfare in Farmed Fishes: The FishEthoBase. Fishes. 4(2):30. https://doi.org/10.3390/fishes4020030

Saraiva, J.L., Rachinas-Lopes, P., Arechavala-Lopez, P. (2022) Finding the "golden stocking density": A balance between fish welfare and farmers' perspectives. Frontiers in Veterinary Science. 9:930221. https://doi.org/10.3389/fvets.2022.930221

Stien, L.H., Bracke, M.B.M., Folkedal, O., Nilsson, J., Oppedal, F., Torgersen, T., et al. (2013) Salmon Welfare Index Model (SWIM 1.0): a semantic model for overall welfare assessment of caged Atlantic salmon. Reviews in Aquaculture. 5(1):33-57. https://doi.org/10.1111/j.1753-5131.2012.01083.x