Jellyfish devastate salmon farm

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The only salmon (Salmo salar) farm in Northern Ireland has been devastated following a series of jellyfish plagues that have wiped out more than a quarter of a million fish in two incidents.

In the first attack, billions of small Mauve stinger jellyfishes (Pelagia noctiluca) killed more than 100,000 salmon (worth in excess of 1 million) of the Northern Salmon Co. Ltd. when they flooded into the fish farm cages in the Irish Sea, off Glenarm Bay in County Antrim.

The jellyfish, covering an area of up to 10 square miles (27 square km) and a depth of 35 feet (13.6 m), killed the salmon with their stings and the induced stress on November 13"14.

The jellyfish were so dense that they slowed down the boats with staff that were trying to rescue the fish long enough to prevent any rescue.

In a second incident on November 23, about 150,000 smolt (young salmon) of the same company were wiped out in a similar attack on its hatchery in Red Bay, about 15 miles (24 km) away from the site of the first attack.

The two attacks threaten the survival of Northern Salmon, which sells its salmon to some of London s finest restaurants, as well as exporting them to hotels and restaurants in France, Belgium, Germany and the United States.

Talks are under way with the government for financial aid, but Agricutlure Minister Michelle Gildernew has ruled out the possibility for now.

In the wake of these incidents, owners of salmon farms in Scotland have been warned to expect potential attacks.

Although there have been jellyfish attacks on fish farms around Britain and the West Coast of Ireland, the mauve stinger jellyfish, blown towards the Antrim coast by winds from the North, have never been recorded in the area before and it is extremely rare for mauve stingers to be found in the colder waters around the British Isles.

Their presence in British waters is thought to be due to wind and tidal factors, although global warming has also been cited as being responsible.