Scientists believed depleted fish stocks have removed competition for jellyfish, allowing them to breed to plague proportions, reported The Courier Mail (18/6/2007, p.13).
Plagues of stingers: Jellyfish blooms, where the creatures multiply rapidly into untold millions:
• clog water intakes on ships and power stations;
• ruin fishing nets; and
• can wreck engines.
Dr Kylic Pitt, from the Griffith University School of Environment, said Japan was experiencing plagues of the giant jellyfish nemopilema. "At more than a metre wide and up to 200kg, they become caught in fishing gear and damage boat engines and mechanical equipment," Pitt said.
Industrial implications: The Port of Brisbane was experiencing blooms of catostylus or blue blubber jellyfish. In 2004, thousands of blue blubbers stopped the P&O cruise ship Pacific Sky from sailing from Brisbane after they were sucked into a water intake. A jellyfish bloom also shut down a coastal power station in Manila in the Philippines in 2000. A survey of Lake Illawarra, near Wollongong in NSW, found it contained 18,000 tonnes of blue blubbers.
The Courier Mail, 18/6/2007, p. 13