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Red Tides a Growing Threat to China's Coast Sunday, October 1, 2000
Environment: Pollution feeds algae that kills fish and costs the nation more than $100 million a year.
By: HENRY CHU
TIMES STAFF WRITERAOTOU, China -- It wasn't quite the biblical apocalypse, when the oceans are supposed to turn to blood, but the "red tide" that just receded from this seaside city still left destruction in its wake.
Thousands of dead fish floated in the bay off Aotou, their glinting carcasses failing to lighten waters blackened by the algae that killed them.
"The sea turned dark, like tea," said Yang Jianxiong, recounting how the fast-breeding algae blanketed the ocean in a matter of days, choking out sunlight and air. "If you talk to the fishermen around here, they'll all break into tears."
Their livelihoods are increasingly threatened by one of China's biggest environmental problems, a little-publicized blight that experts say costs the country more than $100 million every year.
After two decades of breathless economic development--and the pollution and ecological shifts that go with it--severe red tides have begun to plague China's vast coastline, surfacing unexpectedly like thieves and stealing the earnings of millions of people who depend on the ocean's bounty to survive.
The red tides are massive concentrations of microscopic algae that flower and proliferate at tremendous speed. Despite their name, such tides actually vary in color depending on the kind of algae involved, from chocolate to lime green to the blood described in the Book of Revelation.
What many have in common is the potential to harm or destroy aquatic life, either by poisoning the water or depleting its oxygen supply and suffocating the creatures below.
The impact can be devastating. Two years ago, a massive algal bloom near Hong Kong killed up to 75% of the entire stock of Hong Kong's fish farms, wiping out local fishermen and triggering a political outcry in the former British colony.
All told, the Chinese government tallied $240 million in direct economic losses from 45 major red tides between 1997 and 1999 alone.
"I see a serious problem there in China, and I see every sign that it's going to get worse," said Donald Anderson, an expert on red tides and a senior scientist at the Woods Hole Oceanographic Institution in Massachusetts.
China is certainly not the only country afflicted with the problem. Nearly every year, the U.S. experiences serious outbreaks in New England waters. Outbreaks also occur in the Gulf of Mexico and the Pacific Northwest, where residents in the Puget Sound area recently fell ill from consuming shellfish tainted by red tide toxins.
Japan and Korea, too, struggle with algal blooms that have proved deadly to fish and had a negative effect on their maritime economies.
The difference in China is its response to the problem. Whereas the U.S. and Japan have begun taking measures to minimize losses, China--still a developing nation--is struggling to do the same.
"Being aware is one thing; managing [the problem] is something else entirely," said Anderson, who travels frequently to Asian countries, including China, to work with local scientists on combating red tides. "China is learning--in some cases too late--of the nature of red tides and how bad they can be, and is now trying to catch up."
No one can predict exactly when or where such outbreaks will occur. But both man and nature contribute to the problem with industrial and human waste, with nutrients washed into the ocean by rain and with warm weather--conditions that allow the algae to thrive and which the Chinese coast has in spades in summer.
Aotou, perched on the edge of a bay opening onto the South China Sea, has already been the victim of at least two major red tides this season.
The outbreaks ruffle the simple routine of daily life in this picturesque corner of southern Guangdong province, where lush green hills roll down to normally tranquil blue water.
Once the algae reach full bloom, residents have little choice but to wait out the event, which can last anywhere from a few days to several weeks. All of that adds up to lost income for fishermen such as Xu Chengjin.
"When there's a serious red tide, it feels like it lasts for months," said Xu, a weather-beaten 64-year-old whose family has fished off Aotou's shores for at least a century. "There's nothing we can do. If the fish die, they die."
The algae multiply so quickly that at the peak of an invasion in August, a quart of seawater was found to contain about 10 million algae cells.
And the more blooms and outbreaks there are, the more seeds are spread, setting the stage for even larger and more frequent red tides.
"Each year is worse than the last," Xu said one recent morning, the latest contamination still visible in the russet waves that rocked the trawlers moored outside his waterfront home. Poor catches have forced Xu and 90 neighbors in his fishing village to go into debt over the last two years. Together, they owe the local gasoline vendor nearly $25,000--an exorbitant sum for men who each make about $1,000 in a good year.
"My income has dropped by a third," Xu lamented. "Sometimes I catch fish, sometimes I don't."
The story is the same in pockets up and down China's eastern and southern coast, a rugged shoreline spanning at least seven provinces.
The areas hit hardest by the red-tide phenomenon have been Bohai Sea in the northeast, the East China Sea and the South China Sea.
A few months after Hong Kong's catastrophic outbreak in 1998, another flowering took over nearly all of Bohai, covering 2,000 square miles. The algae showed up in satellite images as a luminous green sheath--in contrast to the deep blue of the ocean--and caused an estimated $15 million in damage.
Officials blamed the incident on the massive amounts of waste water and sewage dumped into Bohai, about 700,000 tons a year, according to state media.
Large red tides also regularly grow near China's Zhoushan Islands in the East China Sea, not far from Shanghai, an area whose fish are prized throughout the country for their flavor. And in the south, toxic blooms strike around Guangdong and Fujian provinces.
Anderson, the Woods Hole scientist, credits the Beijing regime with placing emphasis on resolving the problem, spurred partly by the dire economic consequences if poisoned seafood were to be exported.
Public officials here issue regular statements on the need to clean up China's air and water, among the world's dirtiest.
But "they still don't have enough resources and well-trained people," Anderson said. "And they have such a huge coastline that they're going to have a tough time catching up."
Lack of money hamstrings the government. So do poor coordination and duplicated efforts among the bureaucracies responsible for monitoring the seas and mounting responses when red tides appear.
"We need more national research on how to deal with red tides," said Qi Yuzao, professor of hydrobiology at Guangzhou's Jinan University. "The state has to heavily increase its funding."
China has more than 100 monitoring stations scattered along its coast. The outposts rely on reports from residents as well as their own measurements to watch for incipient blooms of algae.
Keeping people informed is key to minimizing economic damage, because most red tides in China occur close to shore, affecting individual fish farmers in shallower waters rather than the big companies engaged in deep-sea harvesting, said Li Xingming, an official with the State Oceanic Administration.
Word is spread through news reports and official notices sent by mail.
If he receives enough warning, Zhao Xiaodou can try to stave off losses by moving his four dozen fish pens to the other side of the bay off Aotou. But there's often not enough time or labor.
"When the water gets warmer and the color turns dark, then you know it's a red tide," said Zhao, 25. "The fish all rise to the surface and [struggle]. We pump oxygen into the water."
During the most recent incursion, Zhao's farm lost about 10% of its stock of around 15,000 fish.
Chinese scientists are experimenting with ways of containing or dispersing red tides once they pop up.
One method involves using a clay that acts as a magnet for algae cells in the water, then sinks to the sea bottom, taking the algae with it.
But no truly effective method is available yet for preventing red tides or stopping them when they start.
Solutions lie in the future, experts say.
"The bottom line is that in the long term, we have to control pollution inputs. We have to control the changes we're making to coastal zones," Anderson said.
Such an effort, however, will likely take decades, he said.