Huge jellyfish swarm wipes out fish farm

Billions of jellyfish in a dense school covering 10 square miles wiped out the entire population of more than 100,000 fish at Northern Ireland’s only salmon farm, the business owners said Wednesday.

Managing Director John Russell said the Northern Salmon Co.’s dozen workers tried to rescue the salmon, worth about $2 million, but their three boats struggled for hours to push through the 35-foot-deep mass of jellyfish. All the salmon were dead or dying from stings and stress by the time the boats reached the two net pens last week, about a mile off the coast of the Glens of Antrim, he said.

Russell, who has worked at Scottish salmon farms and took the Northern Ireland job just three days before the attack, said he had never seen anything like it in 30 years in the business.

“It was unprecedented, absolutely amazing. The sea was red with these jellyfish and there was nothing we could do about it, absolutely nothing,” he said.

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

Russell said the company, which bills its salmon as organic and exports to France, Belgium, Germany and the United States, probably faces closure unless it receives emergency aid from the British government.

“It’s a disaster,” he said.