News

Renewed jellyfish threat

Published on November 17, 2009

Scientists’ warnings of Japanese jellyfish growing big as sumo wrestlers as a consequence of overfishing, have become terrifying reality: a 200-kilo monster recently sunk a big trawler off Chiba on the central East coast.

The trawler, the Diasan Shinsho-maru, capsized as its crew was trying to haul in a net containing dozens of huge Nomuras. The three men onboard were rescued by another trawler, luckily fishing nearby.

The weather was clear and the sea was calm at the time of the accident, the Coast Guard reported.

Earlier this year Dr Anthony Richardson, an Australian marine biologist, warned that marine systems of the world run an acute risk of flipping over to being jellyfish dominated, and mentioned Southeast Asia, the Black Sea, the Gulf of Mexico and the North Sea, as particular problem areas.

He added, prophetically, that the Japanese today have a major problem with giant jellyfish that burst through fishing nets, specifying “a jelly fish called Nomura, which is the biggest jellyfish in the world. It can weigh 200 kilograms, as big as a sumo wrestler and is 2 metres in diameter”.

Jellyfish are normally kept in check by fish, which eat small jellyfish and compete for jellyfish food such as zooplankton. With overfishing, jellyfish numbers are increasing.