Jellyfish wipe out salmon farm

Remember thoss discussions in the last couple of years about how fishing out all the top predaors in the sea would let jellyfish blooms take over and perhaps keep the fish from coming back by killing more young fish. It's happening - and not from predation - by sheer numbers. A flock (school, quiver, bowlful) of jellyfish covering about 10 square miles up to 35 feet deep and engulfed the cages of the only salmon farm in Northern Ireland. The fish were smothered and the owners lost more than a million pounds sterling overnight.

The billions of jellyfish, piled densely in a 35-foot-deep layer, did in the fish through stings and stress, according to John Russell, managing director of Northern Salmon.

The Pelagia nocticula species, or "mauve stinger," ordinarily is found in warmer waters such as the Mediterranean Sea. Scientists pointed to the presence of the jellyfish, rarely seen that far north, as evidence of global warming.

This will be reported in Nature.