Scottish salmon crawling with sea lice, says conservation group


31 Oct 2017 --- Scottish reared salmon – the flagship food product for the country and one of the UK’s most coveted exports – is contaminated with unacceptable levels of sea lice. Data collected by the Salmon and Trout Conservation (S&TC) Scotland reveals “astonishingly” high sea lice levels and claims the Scottish Government’s regulation of salmon farms is proving to be “wholly inadequate.”

The lice-ridden salmon has been supplied to some of the major retailers in the UK and some of the fish have sea lice up to 20 times the acceptable limit, according to S&TC which names and shames what it calls “the liciest fish-farms in Scotland.”

After fighting to obtain information from Scottish ministers, the conservation group now reveals the extent of the sea lice problem. 

It shows that sea lice numbers are running out of control in much of the industry for extended periods and failures by individual farms to operate with lice numbers below Scottish Government’s trigger levels are routine, says S&TC.

A new sea lice regime has been operating since October 2016, but S&TC says it is nowhere near up to scratch. 

Scottish Government’s new trigger levels of three adult female lice per farmed salmon (at which point a “site-specific escalation plan” to reduce lice numbers is required) and eight adult female lice per farmed salmon (at which point, enforcement action may be ordered to harvest early, reduce biomass or cull-out a farm) are considerably more generous to the fish-farmers than the industry’s own longstanding Code of Good Practice (CoGP) sea lice treatment levels of 0.5 or one lice per fish, depending on the time of year.

“Many of the individual farms’ sea lice numbers, which have long been hidden within regional aggregated ‘averages’ published by the industry, are far worse than we envisaged. Sea lice numbers on farmed fish across much of the industry are of epidemic proportions,” said Andrew Graham-Stewart, Director of S&TC Scotland.

“More worryingly, the Scottish Government’s flagship new policy appears to be a sham, little more than a cynical ‘widening of the goalposts’ to the industry’s advantage, a policy with no teeth.”

Guy Linley-Adams, solicitor to S&TC Scotland, adds how the Scottish Government has a legal duty to protect and conserve wild salmon and sea trout.

"The data that Scottish Government didn’t want anyone to see shows that salmon farms have been permitted to operate with breathtakingly high lice numbers for weeks or months on end,” he said.

“To date, no meaningful enforcement action, such as the ordering of culls or immediate reductions in fish-farm biomass, has been taken against serial offenders.

“This data shows it (the government) is failing to rein in the biggest threat to wild salmonids.”

A Scottish Government spokesperson told FoodIngredientsFirst: “Since the enforcement of our new sea lice policy commenced, 24 of 253 farms have reported average adult female lice levels over three, highlighting that over 90 percent of fish farms manage sea lice below this level. The new sea lice policy was adopted to strengthen controls on farmed fish in Scotland and operates in addition to suggested criteria for treatment levels outlined in the code of good practice for Scottish finfish aquaculture.”
“We remain committed to reviewing the policy in future and are working actively with the aquaculture sector to develop a strategic health framework that ensures we make further progress in tackling emerging disease and sea lice.”


Key findings from the published data:

  • The list of those farms that breached the three and/or eight trigger levels includes farms from all the large fish farming companies and most smaller ones.
  • The figures cover the period extending from week 43 in 2016 (November) to week 35 in 2017 (end August) inclusive. 
  • The S&TC  also says that the latest industry aggregated figures show the sea lice problem is getting worse.

“Across the industry as a whole, the upward trend in the failure of salmon farms to control sea lice and stay below the Code of Good Practice (CoGP) threshold of 1 or 0.5 adult female sea lice per farmed fish continues,” it says. 

Regions covering 61.4 percent of total farmed salmon production in Scotland were over CoGP thresholds in June 2017, the last month for which aggregated sea lice data has been published.

Meanwhile, a Parliamentary inquiry is due in early 2018 following a formal petition that was lodged in the Scottish Parliament in February 2016 by S&TC Scotland, seeking protection for wild salmonids from sea lice from Scottish salmon farms.

The Rural Economy and Connectivity Committee of MSPs agreed in July to conduct a full-blown inquiry into salmon farming in Scotland and the issues raised in S&TC Scotland’s petition.

By Gaynor Selby

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