JELLYFISH are found all over the world, from surface waters to the deep sea. Jellyfish have been in existence for at least 500 million years, and possibly 700 million years or more making them the oldest multi-organ animal group. They are boneless, bloodless and brainless. Jellies drift at the mercy of the currents, though many also propel themselves by contracting their domelike bells, pushing water out, while others can recline on the seafloor.
The sting cells used by jellyfish to subdue their prey can also injure humans. Many thousands of swimmers are stung every year, with effects ranging from mild discomfort to serious injury or even death; A box jellyfish native to northern Australian waters, can stop a person’s heart in three minutes. Jellyfish kill between 20 and 40 people a year in the Philippines alone.
Armadas of bluebottle jellyfish have swarmed popular beaches on the Gold Coast and the Sunshine Coast in the state of Queensland, Australia in January this year, stinging more than 13,000 people. Bluebottles were blown a shore or into shallow waters by winds. Bluebottles’ stings can be painful but are typically not dangerous.
Jellyfish numbers have been increasing around the world, causing havoc in some countries. Throngs of jellyfish have disrupted power generation everywhere from Muscat to Maryland, from South Korea to Scotland. Invasive comb jellyfish wiped out a $350 million fishing industry in the Black Sea in 1982. In 2003, 300 tons of jellyfish damaged an intake screen at a desalination plant in Oman cutting its output by 50%. In 2007, Mauve stinger jellyfish killed 100,000 salmon on the country’s only organic salmon farm in Northern Ireland. In 2009, a 10-ton trawler capsized when the crew tried to haul in a net full of Nomura’s jellyfish, which can weigh as much as 150 kg and each grow to the size of large refrigerator.
(To be continued)
