Regulatory Processes for Setting Sensitive-Period Sea-lice Thresholds in Major Salmon Producer Jurisdictions: An Evaluation

Report commissioned by the Aquaculture Stewardship Council (ASC) . Published 2022, 25 p.

Regional variability in the complexity of conditions affecting farm / wild fish interactions calls for a regional approach to sea-lice management. To assist evaluation of whether and to what extent the ASC may rely on the regulatory regimes of major salmon-producing jurisdictions in setting regionally (or locally) relevant “sensitive periods” and sea-lice limits, this report assesses the robustness of regulatory processes for managing the risks to wild salmonids from farm sea lice.

Two of the jurisdictions included in this assessment, the Faroe Islands and Scotland, do not regulate on-farm sea-lice levels for the purpose of protecting wild salmonids. In the Faroe Islands this is due to the limited presence of wild populations. In Scotland, however, the government has recently committed to adopting a new management system for mitigating lice-induced risks to its wild populations, although considerable uncertainty remains as to how the currently lenient on-farm sea-lice thresholds will be updated. Among the jurisdictions assessed here, Norway has implemented the strictest limit-levels for sea lice in recent years; and has, to a larger extent than the other jurisdictions, incorporated the health of wild salmonids into its decision-making through its area-based, “traffic-light” system. In Canada’s British Columbia, sensitive-period trigger levels for delousing actions have remained unchanged since 2004; however, recent updates to conditions of license have enhanced enforceability, and further revisions to improve the protection of wild populations are being considered. The Irish government has not updated its trigger level for treatment since 2008, nor are further revisions planned.

In Norway and more recently Scotland, scientific consensus anchored in a growing body of research that recognizes farm sea lice as a potential hazard to wild salmonids has emerged among government bodies and research institutes. This has underpinned ongoing efforts by the Scottish government to reform its regulatory system, as well as the implementation of gradually more stringent sea-lice regulation in Norway. In Canada and Ireland, on the other hand, scientific controversy around population-level impacts has been notable. Here, aquaculture managers have relied largely on scientific research from researchers in government institutions that argue the population-regulating effects of farm lice are low to negligeable. Thus, scientific research has also underpinned the positions of the Canadian and Irish governments: that existing sea-lice regulations continue to be precautionary in nature.

Wild-salmon stakeholders have not played a major role in setting on-farm thresholds or defining the length of sensitive periods in any of the jurisdictions examined here. However, a general trend towards increasing stakeholder involvement in regulatory processes is evident. In Canada, for example, independent biologists, NGOs and First Nation rights-holders are now consulted and included in efforts to develop multi-stakeholder, area-based management systems for aquaculture in British Columbia.

All the jurisdictions examined here publish farm sea-lice data on a regular basis. In Norway and the Faroes, arrangements promoting frequent data sharing between farms are also in place. In Ireland, and Canada in particular, however, the substantial time-lags between farm sampling and data compilation, and the official publication of such data, have given rise to concerns as regards real-time data transparency in these jurisdictions.



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