Photo: Yomiuri Shimbun/AFP/Getty Images From: http://news.nationalgeographic.com/news/2006/01/0119_060119_jellyfish.html
Imagine pulling up your nets hoping to get a good catch, only to find swarms of Nomura jellyfish 6 feet in diameter, 450 pounds, with hoards of venomous tentacles tainting and killing all your fish. Yay, what a good way to start the day.
In this article, Japanese fishermen are experiencing just this. 2,000 species of jellyfish are experiencing larger populations which are broadening their range and arriving earlier in the season. Scientists speculate that this is due to a change in climate and jellyfish, such as the havoc-wreaking Nomura, are traveling to higher latitudes than usual. Places beyond Japan are experiencing the jellyfish’s sting such as China, Ireland, the Philippines, and Chesapeake Bay.
In the Yellow Sea, it has been concluded that jellyfish are are becoming more dominant due to runoff from agriculture and sewage. This runoff causes the fish population to decline and also sparks larger plankton blooms, paired with the 3 degree warming over the past 25 years – jellyfish are taking over. Not only are these jellyfish attacking the fish industry, but also stinging humans. The Japanese are trying to take advantage of the jellyfish uprising and catch them to make pickled plums or jellyfish ice cream, though the jellyfish industry will never outrank their fishing industry in terms of sushi.
How important is this issue in terms of the health of our ocean? What do you propose should be done?
These jellyfish are fascinating. According to a report by Science Ray, even though these jellyfish are so large, their main diet consists of plankton and small fish. In rare cases, though, they have been recorded to eat their own kind. They paralyze their prey by catching them in cnidocysts, sac-like structures full of toxins and enzymes. Once the prey is paralyzed, it is sucked into the stomach of the jellyfish located in the umbrella portion. As you mentioned, these jellyfish, along with other species, are multiplying at an alarming rate due to warmer ocean temperatures. Right now they seem like more of an nuisance, disrupting the fishing and other ocean related industries. However, Science Ray mentioned that the increase in jellyfish is also disrupting the balance of the food chain by eating so many more fish. They think that if the jellyfish population continues to increase, it could cause a great deal of trouble, not only the fishing industry but also the fragile ecosystems of the Japanese ocean bodies. I wonder if there are other products the Japanese could find to use jellyfish in so they could justify harvesting more of them in attempt to bring the population down.
(Info from http://scienceray.com/biology/zoology/huge-jellyfish-attacks-nomura-jellyfish-the-giant-jelly-of-japan/)
Those jellyfish look really look cool. I think that its cool how they use the jelly fish for food to eat. Do you know if they have every killed any peaople? Accoring to http://news.nationalgeographic.com/news/2009/07/photogalleries/giant-jellyfish-invasion-japan-pictures/index.html, they have costed some fishermen lots of money. Also some scientist have been trying to solve the mystery of wthe jellyfish and they are trying to prevent them from doing anymore damage.
Do you know why they get so big?