Why a strict ceiling on sea lice must be applied to all Scotland’s salmon farms
Wild salmon and sea trout populations in Scotland are dangerously low. For wild salmon and sea trout in the west Highlands and Islands to be properly protected from the negative impact of salmon farming, the effective control of sea lice on farms is a vital first step.
A precautionary approach is essential
S&TCS believes that a genuinely precautionary approach must be applied to the licensing and permitting of any new salmon farms or expansion of existing farms. Such a precautionary approach was also recommended by both the REC and ECCLR Committees in the 2018 Parliamentary Inquiry.
In March 2018, Graeme Dey MSP, Convener of the ECCLR Committee, emphasised the need to apply the precautionary principle to fish farming - “there appears to have been too little focus on the application of the precautionary principle in the development and expansion of the sector…Scotland’s public bodies have a duty to protect biodiversity and this must be to the fore when considering the expansion of the sector. We need to progress on the basis of the precautionary principle …”.
REC Committee (Recommendation 40) was that “although there is a lack of definitive scientific evidence of the various factors that are contributing to the decline of wild salmon stocks, the Committee is nevertheless of the view that a precautionary approach should be taken which will seek to minimise the potential risk to wild salmon stocks wherever possible”.
Put simply, applying the precautionary approach means not using lack of scientific certainty to justify delay in taking action to prevent environmental damage. Where a threat of serious damage has been identified action should be taken to prevent damage occurring. The threat of serious damage to wild salmonids caused by salmon farms has been identified by numerous fisheries scientists, and applying the precautionary principle means putting in place now measures that will prevent salmon farms causing harm to wild salmonids. Waiting to take action until after it has been demonstrated that a particular salmon farm has harmed wild fish is not in accord with the precautionary approach.
In the context of the contested scientific understanding of the negative interactions between farmed and wild fish, fish farm regulation must be underpinned by a robust and strict precautionary approach to protect wild salmonids. Wild salmonid monitoring, particularly in the marine environment, is an imprecise science and is highly unlikely to produce clear and unambiguous results that are not open to multiple different interpretations of what might be occurring.
A strict sea lice ceiling must be applied to all fish farms
Therefore, the precautionary principle demands that adaptive management can only take place under a strict, robust and universally applied sea lice ceiling, in other words an absolute upper limit to the permitted average number of adult female sea lice per farm fish.
Without this ceiling, the burden of proof is effectively reversed, with proof that there is damage being caused to wild salmonids becoming a pre-requisite to any action being taken to address fish farm performance in respect of sea-lice and diseases.
There is already domestic, international and industry support for a strict sea lice ceiling
In November 2018, the Scottish Parliament’s Rural Economy and Connectivity Committee, in its report following its investigations as part of the Inquiry into Salmon Farming, concluded (Recommendation 15) that sea lice triggers should be “challenging” and urged Government to “set a threshold that is comparable with the international industry standards”.
The inter-governmental North Atlantic Salmon Conservation Organization (NASCO) advocates that “100% of farms to have effective sea lice management such that there is no increase in sea lice loads or lice-induced mortality of wild salmonids attributable to the farms”.
In most North Atlantic salmon farming countries statutory on-farm average adult female sea lice limits are set at no more than 0.5 per fish during the critical main wild smolt outward migration period in the spring.
So, why should Scotland’s wild salmon and sea trout be accorded any lesser levels of protection than fish elsewhere?
The Aquaculture Stewardship Council (ASC) certification programme for salmon farming sets global standards for salmon farming (https://www.asc-aqua.org/wp-content/uploads/2019/12/ASC-Salmon-Standard_v1.3_Final.pdf) including for sea lice (Requirement 3.1.7) that “farms seeking certification to maintain on-farm lice levels at 0.1 mature female lice during and immediately prior to sensitive periods, particularly outmigration of wild juvenile salmon”. Mowi (formerly Marine Harvest) claims to be working towards “100 % ASC certification” (https://mowi.com/sustainability/aquaculture-stewardship-council/asc-dashboard/).
So, why should Scotland’s wild salmon and sea trout be accorded aless protection than that recommended by the ASC?
Domestically too, there is support for a strict sea lice ceiling. Scottish Natural Heritage (SNH) has recommended that a strict ceiling for on-farm sea lice levels should be set to protect wild salmonids in the Langavat Special Area for Conservation. In its response to the Screening and Scoping Exercise for the Taranaish fish farm on Loch Roag, SNH required that sea lice control should be based on
“a) The ability of the applicant to maintain average sea lice levels in line with our position paper Marine Aquaculture and Wild Salmonids, see Appendix 1:
0.1 adult female lice per fish between February and June inclusive
0.5 adult female lice per fish between July and January inclusive”.
So, why should Scotland’s wild salmon and sea trout now be accorded less protection than that already recommended by Scotland’s statutory nature conservation body?
Adaptive management, by itself, is not enough…
The Salmon Interactions Working Group’s recently published report proposes a system of adaptive management, but without any precautionary underpinning by a strict universally-applied sea lice ceiling.
Under the SIWG proposals, in effect, wild fish interests would have to prove conclusively that damage is being caused to wild salmon and sea trout before sea lice controls on nearby fish farms were tightened.
Adaptive management will be subject to disagreement between fish farmers and regulators over why wild fish had experienced sea lice infestations and it is likely (in the last resort) that there could be legal challenges from the industry.
Experts within Marine Scotland Science and the Crown Estate agree that it would probably take intense monitoring of wild fish for at least three farm production cycles (up to six years) for any pattern of damage to wild fish caused by fish farms to be established, and even then it will likely be the subject of dispute between fish farmers and regulators over the science.
Therefore, without a strict sea lice ceiling applied to all fish farms from the outset, wild fish would have no more protection from farm-origin sea lice infestation for the foreseeable future. At best, adaptive management alone would, at least for several years, be no more potent in protecting wild fish than the current system. At worst, it will become mired in disputes over what wild fish monitoring is showing and why, leading to no effective control of fish farm production of sea lice.
Why should Scotland’s wild salmon and sea trout be accorded no more effective protection than is currently the case?
Current Scottish Government sea lice reporting levels are not enough
In a letter to S&TCS (June 2020), Cabinet Secretary Fergus Ewing signalled the Scottish Government’s woeful lack of ambition regarding the control of sea lice on farms. Referring to the current sea policy (which only relates to the health and welfare of the farmed fish), he stated that the intention is to enhance “the sea lice reporting process by reducing intervention levels” (currently 2 and 6 average adult female lice per fish – see Marine Scotland Topic Sheet Number 71 V3) “to 2 and 4 in 2021 – unless there is evidence to the contrary”, forgetting that the industry’s current Code of Good Practice already has nominal lice treatment advisory thresholds of 0.5 adult lice per fish (February to June) and 1.0 per fish (July to January).
In other words, farms will not even be required to notify the Fish Health Inspectorate (FHI) of sea lice numbers until the average number of female lice per fish reaches 2 at which point, theoretically, FHI is committed to “increased monitoring/surveillance”, although no other sanction is applied. That is a level fully 20 times the ASC limit during wild smolt runs.
Fergus Ewing’s stated objective amounts to confirmation that Scottish Government does not envisage currently that the future system of adaptive management being proposed will be underpinned by a strict universally-applied and precautionary sea lice ceiling.
S&TCS believes that it is imperative that any new regime includes a strict adult female sea lice ceiling applied to all fish farms, which must be rigorously enforced by tough and prompt action, set at 0.5 per farmed fish, dropping to 0.1 during the period of wild smolt emigration, below which ceiling any adaptive management, based on wild fish monitoring, is then applied.
 See, for example, Friends of the Earth Limited, Re Judicial Review  NICA 41
“37. Given the repeated finding that the operations are likely to have significant impact on the environment the decision maker cannot simply put in the balance the absence of evidence of harm…What has been disregarded … is that these operations are considered likely to have significant impact, that the nature and extent of that impact has not been established, that prior to the grant of permission is the requirement to establish that there will be no significant impact and that it is imperative that the precautionary principle be applied. What must be put in the balance is the absence of evidence that there is no harm. To approach the matter with a requirement for evidence of harm is the negation of the precautionary principle”.