Hugh Pickens writes "The Telegraph reports that the Japanese trawler Diasan Shinsho-maru has capsized off the coast of China, as its three-man crew dragged their net through a swarm of giant jellyfish (which can grow up to six feet in diameter and travel in packs) and tried to haul up a net that was too heavy. The crew was thrown into the sea when the vessel capsized, but the three men were rescued by another trawler. Relatively little is known about Nomura's jellyfish, such as why some years see thousands of the creatures floating across the Sea of Japan on the Tsushima Current, but last year there were virtually no sightings. In 2007, there were 15,500 reports of damage to fishing equipment caused by the creatures. Experts believe that one contributing factor to the jellyfish becoming more frequent visitors to Japanese waters may be a decline in the number of predators, which include sea turtles and certain species of fish. 'Jellies have likely swum and swarmed in our seas for over 600 million years,' says scientist Monty Graham of the Dauphin Island Sea Lab in Alabama. 'When conditions are right, jelly swarms can form quickly. They appear to do this for sexual reproduction.'"