Northern Ireland ? The only salmon farm in Northern Ireland has lost its entire population of more than 100,000 fish, worth some $2 million, to a spectacular jellyfish attack, its owners said Wednesday.

The Northern Salmon Co. Ltd. said billions of jellyfish – in a dense pack of about 10 square miles and 35 feet deep – overwhelmed the fish last week in two net pens about a mile off the coast of the Glens of Antrim, north of Belfast.

Managing director John Russell said the company’s dozen workers tried to rescue the salmon, but their three boats struggled for hours to push their way through the mass of jellyfish. All the fish were dead or dying from stings and stress by the time the boats reached the pens, he said.

The species of jellyfish responsible, Pelagia nocticula – popularly known as the mauve stinger – is noted for its purplish night-time glow and its propensity for terrorizing bathers in the warmer Mediterranean Sea. Until the past decade, the mauve stinger has rarely been spotted so far north in British or Irish waters, and scientists cite this as evidence of global warming.