Norway's Beitstadfjord has been so severely invaded by monster deep sea jellyfish that, just two years since their arrival, they have driven out all of the local fish. The innermost arm of the Trondheimsfjord now holds an estimated 40,000 tonnes of the helmet jellyfish, only a few years after the fiery red peril first appeared in its waters. According to Norway's VG newspaper, Jarle Mork, a researcher at NTNU in Trondheim, caught vast quantities of the slimy animal in a single trawl. "We took up 3.5 tons of monster jellyfish in under ten minutes," he said. "There was a tremendous...