THEY are called echizen kurage and they sound like monsters from the trashier reaches of Japanese science fiction.

They are 6ft wide and weigh 450lb (200kg), with countless poisonous tentacles, they have drifted across the void to terrorise the people of Japan. Vast armadas of the slimy horrors have cut off the country’s food supply. As soon as one is killed more appear to take its place.

Finally, the quarrelsome governments of the region are banding together to unite against the enemy.

Echizen kurage is not an extraterrestrial invader, but a giant jellyfish that is devastating the livelihoods of fishermen in the Sea of Japan. Nomura’s jellyfish, as it is known in English, is the biggest creature of its kind off Japan and for reasons that remain mysterious its numbers have surged in the past few months. Read more...