A MAJOR player in Scotland’s aquaculture sector has defended its practices after a Prince Charles-backed charity claimed its sites were harming wild fish.

Salmon & Trout Conservation Scotland (S&TCS), which counts the senior Royal as patron, blames the Scottish Salmon Company (SSC) for the parasite deaths of a “substantial proportion” of wild adult salmon in the Hebrides.

The organisation says it has video evidence that a “plague” of killer sea lice hit wild adult salmon on the Blackwater River on Lewis, which flows into Loch Roag, where SSC has seven farm facilities.

It claims wild fish passing through the water body were “smothered with many hundreds of sea lice”, suffering unsurvivable damage to their skin, and that the pests are the result of SSC activity.

Animal charity SSPCA is investigating but S&TCS says local wildlife and related businesses are at risk and legislation must now be changed.

Meanwhile, it has released images of tonnes of farmed fish taken by tanker to North Uist and dumped in a pit on the sands. SSC did not comment on that claim, but a spokesman stated the lice are “endemic” in the wild and it has invested in management measures in the area.

He added: “Fish health and welfare is central to responsible salmon farming and we take this very seriously. However, as with any farmed stock, mortalities can occur and this has been exacerbated by the warm weather this summer. Following receipt last week of video footage and photographs, the SSPCA visited at random a number of sites.

“The Scottish Salmon Company have not had an opportunity to examine or authenticate this information, but openly facilitated the SSPCA visits and look forward to receiving their feedback.”

Meanwhile, S&TCS solicitor Guy Linley-Adams said: “The law is insufficient to protect wild fish from this sort of event. We desperately need MSPs to act quickly to plug this gap in Scottish law. Currently, there is no regulatory body that is responsible for protecting wild salmon from the impacts of salmon farming and so one of Scotland’s most iconic species is under serious threat.

“The Fish Health Inspectorate has been to the Roag farms, but the law means it is only able to involve itself in the health and welfare of the farmed fish, though the truckloads of mortalities that have been seen suggest it has not been very successful.”

Investigations into falling populations of wild salmon are under way around Scotland. On the Blackwater losses, S&TCS director Andrew Graham-Stewart added: “These fish were literally eaten alive and a large number of adults, that would have bred in the river, have been killed by the lice. Laboratory tests have failed to find any other possibility.”

He went on: “This episode represents exceptionally strong evidence of how lice on fish farms, where many hundreds of thousands of fish are packed close together in cages, can increase rapidly in number and release vast numbers of juvenile lice into the surrounding waters. This can have absolutely devastating consequences for wild fish populations.

“The loss of a very substantial proportion of the Blackwater River adult salmon run this year has severe implications for spawning and thus future salmon numbers. Furthermore, if sea lice numbers were high during May and June, then migrating wild juvenile salmon are likely to have been badly infested, compromising their survival chances.

“On top of that, local rural businesses that rely on wild salmon are under threat.”

Marine Scotland, the Holyrood agency which overseas aquaculture, was contacted for comment.

A government spokesman said: “Marine Scotland is currently investigating concerns raised by a member of the public regarding lice at a fish farm in Lewis, and will be carrying out an inspection on the site imminently. We take submissions of this nature seriously, and are working to establish the facts on this case before coming to an informed position.”