Coastal havoc boosts jellies

摘要

"It was a truly gelatinous world" says marine ecologist Sun Song, recalling a jellyfish outbreak last year in the Yellow Sea off Chinas eastern coast. "The slimy monsters were everywhere, their long tentacles fluttering ferociously in the rolling waves." Such blooms have repeatedly choked Chinese waters in the past decade, posing substantial threats to tourism, fisheries and coastal facilities such as chemical plants and nuclear power stations. Jellyfish blooms have probably struck the worlds seas periodically for hundreds of millions of years. But researchers suspect that human activity has made them worse, with knock-on effects on marine ecosystems and especially on fish, because jellyfish compete with fish for food and feed on their larvae. Now, one of the largest studies of jellyfish blooms so far - involving laboratory testing, ocean surveys and field experiments - has found direct evidence linking the proliferation of jellyfish to human disturbances along the coast, especially the disruption of sea-floor ecosystems.