
Jellyfish are Decimating Japanese Fishing
- KOKONOGI, Japan βThe 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 β the warming of oceans β 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.
- “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.
- Hearing fishermen’s pleas, Uye, who had been studying zooplankton, became obsessed with the little-studied Nomura’s jellyfish, scientifically known as Nemopilema nomurai, which at its biggest looks like a giant mushroom trailing dozens of noodle-like tentacles.
- “No one knew their life cycle, where they came from, where they reproduced,” said Uye, 59. “This jellyfish was like an alien.”
- He artificially bred Nomura’s jellyfish in his Hiroshima University lab, learning about their life cycle, growth rates and feeding habits. He traveled by ferry between China to Japan this year to confirm they were riding currents to Japanese waters.
- He 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.
- Addressing the surge in jellyfish blooms in most places will require long-term fixes, such as introducing fishing quotas and pollution controls, as well as capping greenhouse gas emissions to control global warming, experts said.
- In the short term, governments are left with few options other than warning bathers or bailing out cash-strapped fishermen. In Japan, the government is helping finance the purchase of newly designed nets, a layered system that snares jellyfish with one kind of net, allowing fish through to be caught in another.
- Some entrepreneurs, meanwhile, are trying to cash in. One Japanese company is selling giant jellyfish ice cream, and another plans a pickled plum dip with chunks of giant jellyfish. But, though a popular delicacy, jellyfish isn’t likely to replace sushi or other fish dishes on Asian menus anytime soon, in view of its time-consuming processing, heavy sodium overload and unappealing image.
