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Wednesday, November 18, 2009

Jellyfish swarm northward in warming world


"The fishermen leaned into the nets, grunting and grumbling as they tossed the translucent jellyfish back into the bay, giants weighing up to 200 kilograms (450 pounds), marine invaders that are putting the men's livelihoods at risk.

The venom of the Nomura, the world's largest jellyfish, a creature up to 2 meters (6 feet) in diameter, can ruin a whole day's catch by tainting or killing fish stung when ensnared with them in the maze of nets here in northwest Japan's Wakasa Bay.

"Some fishermen have just stopped fishing," said Taiichiro Hamano, 67. "When you pull in the nets and see jellyfish, you get depressed."

This year's jellyfish swarm is one of the worst he has seen, Hamano said. Once considered a rarity occurring every 40 years, they are now an almost annual occurrence along several thousand kilometers (miles) of Japanese coast, and far beyond Japan.

Scientists believe climate change -- the warming of oceans -- has allowed some of the almost 2,000 jellyfish species to expand their ranges, appear earlier in the year and increase overall numbers, much as warming has helped ticks, bark beetles and other pests to spread to new latitudes.

The gelatinous seaborne creatures are blamed for decimating fishing industries in the Bering and Black seas, forcing the shutdown of seaside power and desalination plants in Japan, the Middle East and Africa, and terrorizing beachgoers worldwide, the U.S. National Science Foundation says.

A 2008 foundation study cited research estimating that people are stung 500,000 times every year -- sometimes multiple times -- in Chesapeake Bay on the U.S. East Coast, and 20 to 40 die each year in the Philippines from jellyfish stings.

In 2007, a salmon farm in Northern Ireland lost its more than 100,000 fish to an attack by the mauve stinger, a jellyfish normally known for stinging bathers in warm Mediterranean waters. Scientists cite its migration to colder Irish seas as evidence of global warming.

Increasingly polluted waters -- off China, for example -- boost growth of the microscopic plankton that "jellies" feed upon, while overfishing has eliminated many of the jellyfish's predators and cut down on competitors for plankton feed.

"These increases in jellyfish should be a warning sign that our oceans are stressed and unhealthy," said Lucas Brotz, a University of British Columbia researcher. "

The invasions cost the industry up to 30 billion yen ($332 million) a year, and tens of thousands of fishermen have sought government compensation, said scientist Shin-ichi Uye, Japan's leading expert on the problem.

  Uye has concluded China's coastal waters offered a perfect breeding ground: Agricultural and sewage runoff are spurring plankton growth, and fish catches are declining. The waters of the Yellow Sea, meanwhile, have warmed as much as 1.7 degrees C (3 degrees F) over the past quarter-century.

"The jellyfish are becoming more and more dominant," said Uye, as he sliced off samples of dead jellyfish on the deck of an Echizen fishing boat. "Their growth rates are quite amazing."

The slight, bespectacled scientist is unafraid of controversy, having lobbied his government tirelessly to help the fishermen, and angered Chinese colleagues by arguing their government must help solve the problem, comparing it to the effects of acid rain that reaches Japan from China.

"The Chinese people say they will think about this after they get rich, but it might be too late by then," he said.

A U.S. marine scientist, Jennifer Purcell of Western Washington University, has found a correlation between warming and jellyfish on a much larger scale, in at least 11 locations, including the Mediterranean and North seas, and Chesapeake and Narragansett bays.

"It's hard to deny that there is an effect from warming," Purcell said. "There keeps coming up again and again examples of jellyfish populations being high when it's warmer." Some tropical species, on the other hand, appear to decline when water temperatures rise too high.


To read the remainder of  this article please click on the following link:

http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20091117/jellyfish_warm_091117/20091117?hub=SciTech

Here is a short National Geographic video about Jellyfish




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Thoughts worth thinking about

"Our subconscious minds have no sense of humor, play no jokes and cannot tell the difference between reality and an imagined thought or image. What we continually think about eventually will manifest in our lives."-Sidney Madwed



Laws alone can not secure freedom of expression; in order that every woman and man present their views without penalty, there must be spirit of tolerance in the entire population.- Albert Einstein Too often we underestimate the power of a touch, a smile, a kind word, a listening ear, an honest compliment, or the smallest act of caring, all of which have the potential to turn a life around. - Leo Buscaglia



A person's true wealth is the good he or she does in the world. - Mohammed



Our task must be to free ourselves... by widening our circle of compassion to embrace all living creatures and the whole of nature and its beauty. -Albert Einstein



The best way to find yourself, is to lose yourself in the service of others. - Ghandi



The unselfish effort to bring cheer to others will be the beginning of a happier life for ourselves. - Helen Keller



Aim for success, not perfection. Never give up your right to be wrong, because then you will lose the ability to learn new things and move forward with your life. Remember that fear always lurks behind perfectionism. Confronting your fears and allowing yourself the right to be human can, paradoxically, make yourself a happier and more productive person. - Dr. David M. Burns



Life is as dear to a mute creature as it is to man. Just as one wants happiness and fears pain, just as one wants to live and not die, so do other creatures. -His Holiness The Dalai Lama



Mankind's true moral test, its fundamental test (which lies deeply buried from view), consists of its attitude towards those who are at its mercy: animals. And in this respect mankind has suffered a fundamental debacle, a debacle so fundamental that all others stem from it. -



Milan Kundera, The Unbearable Lightness of Being



The worst sin towards our fellow creatures is not to hate them, but to be indifferent to them. That's the essence of inhumanity. -George Bernard Shaw

Ego's trick is to make us lose sight of our interdependence. That kind of ego-thought gives us a perfect justification to look out only for ourselves. But that is far from the truth. In reality we all depend on each other and we have to help each other. The husband has to help his wife, the wife has to help the husband, the mother has to help her children, and the children are supposed to help the parents too, whether they want to or not.-Gehlek Rinpoche Source: "The Best Buddhist Writing 2005 pg. 165

The hostile attitude of conquering nature ignores the basic interdependence of all things and events---that the world beyond the skin is actually an extension of our own bodies---and will end in destroying the very environment from which we emerge and upon which our whole life depends.