The jellyfish blooms are much worse than I thought so I thought I would reprint here online articles I found printed in recent years on the increasing problem worldwide.
The following is the internet address for the article I will reprint afterwords
http://www.news.com.au/couriermail/story/0,23739,21922334-5007200,00.html
A JELLYFISH plague is threatening shipping and fishing worldwide.
Scientists believe depleted fish stocks have removed competition for jellyfish, allowing them to breed to plague proportions.
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.
Kylie 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," Dr Pitt said.
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 Moreton Bay Seafood Industry Association also had reported problems with jellyfish clogging Brisbane River trawler nets.
"At times they are in absolutely enormous quantities," Dr Pitt said.
Port of Brisbane Authority environment manager Brad Kitchen said blooms were not a major issue for the port.
"It's mainly just the ships with bow thrusters (used to turn ships) that have to be careful," Mr Kitchen said.
"Bow thrusters can get clogged."
Although Australia did not yet have the feared nemopilema blooms, jellyfish could spread quickly world-wide through ballast water.
Mr Kitchen said in an effort to avoid exotic species being transported to Brisbane, all ships entering the port were obliged to dump ballast and take on deep sea water off the continental shelf before entering Moreton Bay. end article reprint
internet address where I found the following article
http://scienceblogs.com/shiftingbaselines/2007/06/jellyfish_bloom_and_doom.php
Jellyfish Bloom and Gloom
Category: Losing Track
Posted on: June 24, 2007 10:35 AM, by Jennifer L. Jacquet
Jeremy Jackson calls it "The Rise of Slime". Daniel Pauly sees a future in jellyfish burgers. And given that this week is the 2nd International Jellyfish Bloom Symposium--where D. Pauly will deliver the keynote address (having not been able to attend the 1st symposium in Alabama in 2002)--it seemed fitting this week should be dedicated to jellyfish bloom and gloom.
Jellyfish, given their lowly position on the marine food chain and their penchant for degraded ecosystems, are, after all, the darlings of shifting baselines. They are the reality of our marine future unless we decide to change.
Jellyfish Blooms: No Bed of Roses
The removal of predatory fish throughout the world's oceans (by commercial fisheries to feed humans and what we eat) combined with nutrient runoff (jargon for 'sewage') have made the perfect ocean petri dish for jellyfish blooms. These 'blooms' are no blossoms, but more like explosions of jellies--a global jellyfish boom.
A 2005 report in Science showed that jellyfish blooms in the Yangtze River are in direct competition with fish for food. Inedible jellyfishes now make up 98.44% of total catches and clog the nets of trawlers in the river's mouth (the same trawlers pehaps responsible for making marine ecosystems amenable to jellyfish).
Last summer, the entire Mediterranean was on jellyfish alert and more than 30,000 people were stung. In some areas off the Spanish coast, scientists with Oceana found more than 10 jellyfish per square meter.
Japan slowed down a nuclear power plant last summer because jellyfish were blocking the water intake, which is easy to imagine given the size of some jellyfish in the area (including the 200-kg jelly in the photo above found off Japan's shores in October 2005).
In the Gulf of Mexico, all species of jellyfish are rapidly increasing and overlapping with prime fishing grounds, such as those for Red snapper. Moon jellyfish are being found in concentrations so dense they're described as gelatinous nets.
This week, I will take a closer look at jellyfish. In the meantime, more bloom and gloom:
A report last week from Australia discusses how jellyfish impeding shipping and fishing worldwide.
end of reprinted article
There was the 2nd international Jellyfish Blooms Symposium in Australia. The first was held in Alabama in 2000.
http://www.griffith.edu.au/conference/jelly2007/
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