Lice not a ‘significant’ salmon threat

Sea lice are not playing a “significant role” in killing off salmon stocks, joint research by the Marine Institute and NUI Galway has claimed.

In a study published in the trade magazine Journal of Fish Diseases, the group said it is “unlikely” any infestation by the parasite risks causing devastation to the salmon industry.

However, the comment is expected to provoke fury from opponents who insist the sea lice problem is damaging local economies in coastal areas.

According to the Marine Institute research — which was based on tests of more than 350,000 fish over a nine-year period — the “level of marine mortality attributable to sea lice infestation is very small — approximately 1%”.

“At these levels, it is unlikely to influence the conservation status of stocks and is not a significant driver of marine mortality,” the study said.

The finding contradicts previous research into the issue, which fishermen fear could cause havoc to the salmon industry.

However, the Marine Institute argued this is because of “serious flaws” in previous studies.

Pointing to a rise in salmon deaths since 2008, the research team said: “There is no evidence to suggest this trend is influenced by sea lice infestation levels of outwardly migrating smolts as treated and control fish are equally affected.”

Last month the Save Bantry Bay pressure group wrote to Marine Minister, Simon Coveney, warning sea lice from salmon farms are causing a 40-50% in wild salmon stocks — severely damaging the local economy.