tagged w/ Algae Blooms
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Toxic algae is sucking the oxygen out of Lake Erie.
The lake is currently undergoing one of the worst algae blooms in decades, turning the water a scummy bright green. According to NASA, blooms like this did occur in the 1950's and 60's, but now phosphorus from farms, sewage, and industry have fertilized the waters.
After the 60's, increased regulations and improvements in agriculture and sewage treatment limited the phosphorus and helped to control the blooms. However, the shallower Western basin near Detroit has been more susceptible to the algae than other deeper areas.
The exact reason behind the bloom is a bit unclear, but scientists believe it could be linked to increased rainfall and, believe it or not, mussels. It seems the types of mussel, zebra and quagga that have invaded the lake feed on phytoplankton instead of algae, making it even easier for the blooms to occur, according to NASA.
While the algae doesn't directly kill fish, it's still not good. As the algae dies, it's broken down by bacteria which uses oxygen from the water. This oxygen removal creates areas where fish can't survive. In addition, if consumed, it can also create flu-like symptoms in people or even kill pets.
Former Vice President Al Gore spoke Thursday in Detroit on the matter, associating climate change with the algae problem. "We're still acting as if it's perfectly OK to use this thin-shelled atmosphere as an open sewer. It's not OK," he said. "We need to listen to the scientists. We need to use the tried and true method of using the best evidence, debating and discussing it, but not pretending that facts are not facts."
While in the past, some have criticized Gore, claiming that he's made exaggerated statements about the environment, yesterday's speech drew upon some pretty hard scientific evidence, leading many leaders at the International Joint Commission to listen a bit more intently.
More at the linkToxic algae is sucking the oxygen out of Lake Erie.
The lake is currently... more
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Marine officials were trying to determine Tuesday what caused thousands of sardines to turn up dead in Ventura Harbor, the second mass fish die-off in local marinas in as many months.
Roughly 6 tons of the small silvery fish were found floating in the harbor early Monday. Officials said their initial theory is that the sardines died after using up all the oxygen in a corner of the harbor.
The scene in Ventura Harbor — crews churning up the water with aerators and volunteers scooping nets full of fish up from the surface — was reminiscent of the cleanup effort in Redondo Beach six weeks ago when officials discovered a thick blanket of dead sardines coating King Harbor.
Scientists are looking into whether the two die-offs share a common cause.
A spokesman for the California Department of Fish and Game said a warden visited the harbor and concluded the die-off was the result of oxygen deprivation, not water pollution, toxins or algae blooms — the usual causes of fish kills.
Last month's massive die-off occurred after millions of sardines swam into King Harbor and suffocated. It took days for crews to scoop and vacuum up about 175 tons of fish carcasses from the harbor.
Those sardines tested positive for domoic acid, a neurotoxin generated by algae blooms, but scientists believe the fish — perhaps disoriented because of the toxic algae — swam into the enclosed harbor in such huge numbers that they died as a result of critically low oxygen levels, not poisoning. Still, what caused them to swim into the marina remains a mystery.
The die-off in Ventura appears to be much smaller.
Large schools of fish started to swim into Ventura Harbor about a week ago, Harbormaster Scott Miller said; it was unclear what drove them there. Dolphins, sea lions and seabirds followed, feasting on the heavy concentration of easy prey.
"We just think they moved in there, and it was just like crowding too many people into a room," he said.
An algae bloom along the coastline in recent weeks has poisoned dozens of sea lions, dolphins and seabirds and left them stranded on beaches across Southern California, but scientists have not linked either of the fish kills to the bloom.
USC biology professor David Caron said his lab was requesting fish specimens from Ventura Harbor to test for specific toxins related to algae blooms.
cont.Marine officials were trying to determine Tuesday what caused thousands of sardines to... more
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Global warming could spur the growth of toxic algae and bacteria in the world's seas and lakes, with an impact that could be felt in 10 years, US scientists said Saturday.
Studies have shown that shifts brought about by climate change make ocean and freshwater environments more susceptible to toxic algae blooms and allow harmful microbes and bacteria to proliferate, according to researchers from the National Oceanic and Atmospheric Administration (NOAA).
In one study, NOAA scientists modeled future ocean and weather patterns to predict the effect on blooms of Alexandrium catenella, or the toxic "red tide," which can accumulate in shellfish and cause severe symptoms, including paralysis, in humans who eat the contaminated seafood.
"Our projections indicate that by the end of the 21st century, blooms may begin up to two months earlier in the year and persist for one month later compared to the present-day time period of July to October," said Stephanie Moore, one of the scientists who worked on the study.
But the impact could be felt well before the end of this century -- as early as 2040, she said at the annual meeting of the American Association for the Advancement of Science.
"Changes in the harmful algal bloom season appear to be imminent. We expect a significant increase in Puget Sound (off the coast of Washington state where the study was conducted) and similar at-risk environments within 30 years, possibly by the next decade," said Moore.
cont.
Also see:
http://news.nationalgeographic.com/news/2011/03/110301-global-warming-health-science-environment/Global warming could spur the growth of toxic algae and bacteria in the world's... more
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Mon May 17, 2010 4:59 PM EDT
By The Rachel Maddow Show
(Times-Picayune graphic)
Years before the Deepwater Horizon disaster, before the underwater volcano of oil threatened to create a dead zone in the Gulf of Mexico, scientists recognized another dead zone in the Gulf. The New Orleans Times-Picayune won a Pulitzer in 1997 for documenting the devastation around the mouth of the Mississippi River. The 7,000-square-mile dead zone was caused by algae blooms, feeding on agricultural and sewer runoff, that deplete the oxygen in the water.
http://www.pulitzer.org/archives/6010
Ten years later, the Times-Picayune found this dead zone was still growing:
"You reach a point where you've shifted the ecosystem to a completely different domain, and the recovery from that may be impossible," said Don Scavia, a professor of natural resources and environment at the University of Michigan and former National Oceanic and Atmospheric Administration scientist who led one of the first federal studies on the dead zone in 2000. "There will be a time where the critters that typically occupy the sediment in those areas can no longer recover."Mon May 17, 2010 4:59 PM EDT
By The Rachel Maddow Show
(Times-Picayune graphic)... more
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Hundreds of birds—including this loon pictured on the Oregon coast—are washing up on the shores of the U.S. Pacific Northwest coated with a foamy sea slime, scientists say.
The slime, which comes from algae blooms in the ocean, saps the waterproofing ability of the birds' feathers, experts say. Untold hundreds have died, succumbing to hypothermia or predators such as eagles, Holcomb added.
Nearly 500 of the slimed birds have been transported to the rescue center in Fairfield, California, which was specially built to care for coastal wildlife contaminated with oil. Many of the slime victims have been released.
Several hundred more birds are also being treated at facilities in Oregon and Washington State.
Article continues: http://news.nationalgeographic.com/news/2009/10/091030-sea-slime-birds-picture.html
PHOTO CREDIT: NATIONAL GEOGRAPHICHundreds of birds—including this loon pictured on the Oregon coast—are... more
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France – It should have been a perfect day for Vincent Petit, finishing up an afternoon gallop on a wide expanse of beach along a pastel-colored bay. Instead, he and his mount were sucked into a hole of noxious black sludge.
The horse died within seconds, the rider lost consciousness and a dirty secret on the Brittany coast reverberated across France — decaying green algae was fouling some of its best beaches.
A report ordered by the government after the accident found concentrations of hydrogen sulfide gas emitted by the rotting algae were as high as 1,000 parts per million on the beach where the horse died — an amount that "can be fatal in several minutes."
There had been signs of a crisis for years in this idyllic corner of Brittany. But scaring away tourists was in no one's interest, including the farming industry — the region's economic backbone — whose nitrate-packed fertilizers power algae blooms.
So, while tongues wagged, folks whispered and acrimony grew, an official hush prevailed. It took the death of the horse to bring the problem into the open.
Decaying ulva algae threatens other beaches around France and the world, from the United States to China, experts say. Last year, the Chinese government brought in the army to remove the slimy growths so the Olympic sailing competition could be held.
In Brittany's Cote d'Armor region, conditions are perfect for its spread — sunlight, shallow waters and flat beaches. Chemical and natural fertilizers like pig excrement, loaded with nitrates and phosphorous, have saturated the land, spilling into rivers and the ocean, feeding the algae that then proliferate.
Harmless while in water, the algae form dangerous gases — notably hydrogen sulfide, with its characteristic rotten-egg smell — when they wash up on land and decay. A white crust forms and traps the gases, which are released when stepped on or otherwise disturbed. Over time, putrefied algae turns sand into a black silt muck, sometimes containing pockets of poison gas.
On July 28, Petit, a 28-year-old researcher in a state-run virology lab, had just finished riding his thoroughbred Sir Glitter, a retired racehorse, on the Saint-Michel-en-Greves beach, when the two were suddenly mired in muck as he led the horse on foot in search of a place to cross a stream running through the sand.
"The horse and I slid in," said Petit, who is also trained in veterinary studies. "A horse in that situation is in an enormous panic, but he didn't have time to struggle."
Petit said he watched horrified as his horse stopped breathing and died within about 30 seconds, then he himself passed out. Petit was pulled from the mire by a bulldozer shovel after a man who witnessed the accident gave the alert.
While locals are aware of the perils posed by the silt traps that lurk under the sand around streams that feed from the beach into the ocean, Petit did not sense the danger until the ground gave way and he and his horse were sucked into the noxious ooze up to the man's chest.
Police initially ruled the horse suffocated, but an autopsy showed the animal died of an acute pulmonary edema with symptoms "compatible with gaseous intoxication in a brutal manner," Petit said, quoting the report, which he paid for.
There was no foreign matter in the horse's throat, lungs or stomach and no sign of a heart attack, he said.
There have been local efforts to clear the blight. Mayor Rene Ropartz said Saint-Michel-en-Greve, a village of 480 people, collected 10,000 tons of algae from the mile-long beach by the end of July; several years ago they cleaned up 21,000 tons.
"This bay is magnificent and, unfortunately, this tarnishes the image," said Ropartz, adding that the horse's death shows the role of the algae "is no longer in doubt" and spurred the government into action.
endFrance – It should have been a perfect day for Vincent Petit, finishing up an... more
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