NorCalFlyGuy
05-27-2006, 08:23 AM
DIDYMO is even more damaging than mudsnails, much faster acting, and threatens to wreak havoc on western trout streams unless it is dealt with now
in NZ, they've experienced 75% declines in trout populations of some rivers in as little as 2 years after Didymo was discovered
friends in NZ told me this is devastating some of the best rivers in the country and reports of it in CO, MT and other western states means it's headed our way
articles and resources:
http://www.google.com/search?hl=en&q=didymo
http://www.tva.gov/river/neighbors/aug05/algae.htm
http://www.doc.govt.nz/Explore/Hunting-and-Fishing/Taupo-Fishery/014~Didymo.asp
Slimy alga threatens state rivers
============================================
Posted May 18, 2006 - 10:20 AM
By MIKE STARK
The Billings Gazette
BIG TIMBER - Call it rock snot. Call it didymo. Call it the tenacious slime that can gunk up a river quick and send a mess of tufts resembling wet toilet paper down pristine waterways.
This alga, formally called Didymosphenia geminata, typically has been a rare and retiring species, barely noticed in waters of northern latitudes. Lately, though, it has exploded in "nuisance blooms" in some areas, creating thick mats across stream beds and potentially disturbing the lives of insects, fish and others in the water.
"If they took a big shag carpet out of the living room and draped it across a river -- that's what it looks like," said David Beeson, a Denver-based environmental consultant.
Beeson, whose been monitoring the East Boulder River since 1998, said didymo showed up in low levels until 2004, when it abruptly spread from bank to bank at several spots.
"Suddenly, it was just there," he said.
On Monday, scientists from around the country and other nations met in Bozeman to talk about the spread of didymo.
They visited a stretch of the Boulder River outside Big Timber on Tuesday to look for evidence of the alga and talk about the implications if the moss-like mats continue to spread.
"My concern is that it could be fundamentally changing streams," said Sarah Spaulding, a scientist with the U.S. Geological Survey in Denver who has been tracking didymo and helped organize this week's conference.
Excessive growths of didymo have been recorded in recent years on the Boulder and Kootenai rivers along with others in Montana, Idaho, Colorado, Washington, South Dakota and elsewhere in the United States. In some places, the growths cover more than 10 miles.
Barry Biggs has been seen the damage the outbreaks can have on stream life in New Zealand.
Didymo was first discovered in high densities in the fall of 2004 along the Mararoa and Waiau rivers in the country's Southland.
The slime squeezed out mayflies and caddis flies, a food staple of brown and rainbow trout. Midges and other smaller critters survived in the muck but when trout fed in those areas, they gulped down huge amounts of low-nutrient didymo with their meals.
"They had guts that were full of didymo. It looked like mats of cotton," said Biggs, who works for the country's National Institute of Water and Atmospheric Research.
In those areas, the number of trout has dropped 75 percent since the blooms of didymo began less than two years ago.
A publicity campaign has heightened didymo's profile in New Zealand and urged the public to take measures to prevent its spread. In North America, though, didymo is hardly familiar.
"It's totally off the radar screen," said Max Bothwell of Environment Canada, a federal agency.
Bothwell watched as didymo spread across Vancouver Island, where the first large-sized blooms showed up in the late 1980s.
The outbreak has died down in recent years, but scientists are still unsure about what triggered it.
The alga is native to parts of North America but typically doesn't erupt in the kind of nuisance blooms that have been seen in recent years.
"Something's going on," said Spaulding. "This isn't normal."
Didymo is tough and clings stubbornly to rocks when river flows are steady. It's often washed away in heavy flows.
When it does break off the rocks, it floats downstream. The slippery, gray tufts have been compared to wet toilet paper -- an unappetizing sight.
When didymo showed up outside Vail, Colo., people called authorities to report there was sewage in the water, Spaulding said.
So not only does the alga pose potential problems for the function of the stream, it also poses an aesthetic problem for anglers, who also have to deal with tangles of didymo on their lines, and other water recreationists, she said.
And when anglers begin to stay away from rivers for that reason, didymo poses an economic problem for communities that rely on fishermen who stay in hotels, eat at restaurants and buy groceries.
Scientists believe didymo spreads from river to river primarily by anglers, boaters and other people who move from one area to the next. Researchers in New Zealand recently found that the alga can survive for 40 days out of the water on a piece of equipment, Spaulding said.
Leah Elwell, conservation coordinator for the Federation of Fly Fishers in Livingston, said anglers should do the same thing they do to prevent the spread of other non-native species: check their gear before they leave an area and pick off any muck, clean gear thoroughly with a disinfectant and allow it to dry completely before using it again.
Even though there is still much to learn about didymo and its potential effects, it behooves the public and land managers to take it seriously and take measures to prevent its spread, said those at the conference.
"We can't afford to play this Russian roulette at this point," Biggs said.
Slimy algae draws scientists to Bozeman
=================================================
BOZEMAN Scientists from around the world are gathering in Bozeman today, for a conference on a slimy algae that is taking over streams in North America, New Zealand and Europe.
The algae, commonly called didymo, creates thick stalks that can clog canals and intakes and make it difficult for bugs, nymphs and fish to survive.
Outbreaks can extend for miles. In some places, it's considered an invasive species.
In Montana, major outbreaks have occurred on the East Boulder River south of Big Timber and the Kootenai River in northwest Montana.
Scientists are gathering at the conference to share information about didymo and discuss how to control it.
They plan to tour the outbreak on the East Boulder River tomorrow.
Copyright 2006 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
in NZ, they've experienced 75% declines in trout populations of some rivers in as little as 2 years after Didymo was discovered
friends in NZ told me this is devastating some of the best rivers in the country and reports of it in CO, MT and other western states means it's headed our way
articles and resources:
http://www.google.com/search?hl=en&q=didymo
http://www.tva.gov/river/neighbors/aug05/algae.htm
http://www.doc.govt.nz/Explore/Hunting-and-Fishing/Taupo-Fishery/014~Didymo.asp
Slimy alga threatens state rivers
============================================
Posted May 18, 2006 - 10:20 AM
By MIKE STARK
The Billings Gazette
BIG TIMBER - Call it rock snot. Call it didymo. Call it the tenacious slime that can gunk up a river quick and send a mess of tufts resembling wet toilet paper down pristine waterways.
This alga, formally called Didymosphenia geminata, typically has been a rare and retiring species, barely noticed in waters of northern latitudes. Lately, though, it has exploded in "nuisance blooms" in some areas, creating thick mats across stream beds and potentially disturbing the lives of insects, fish and others in the water.
"If they took a big shag carpet out of the living room and draped it across a river -- that's what it looks like," said David Beeson, a Denver-based environmental consultant.
Beeson, whose been monitoring the East Boulder River since 1998, said didymo showed up in low levels until 2004, when it abruptly spread from bank to bank at several spots.
"Suddenly, it was just there," he said.
On Monday, scientists from around the country and other nations met in Bozeman to talk about the spread of didymo.
They visited a stretch of the Boulder River outside Big Timber on Tuesday to look for evidence of the alga and talk about the implications if the moss-like mats continue to spread.
"My concern is that it could be fundamentally changing streams," said Sarah Spaulding, a scientist with the U.S. Geological Survey in Denver who has been tracking didymo and helped organize this week's conference.
Excessive growths of didymo have been recorded in recent years on the Boulder and Kootenai rivers along with others in Montana, Idaho, Colorado, Washington, South Dakota and elsewhere in the United States. In some places, the growths cover more than 10 miles.
Barry Biggs has been seen the damage the outbreaks can have on stream life in New Zealand.
Didymo was first discovered in high densities in the fall of 2004 along the Mararoa and Waiau rivers in the country's Southland.
The slime squeezed out mayflies and caddis flies, a food staple of brown and rainbow trout. Midges and other smaller critters survived in the muck but when trout fed in those areas, they gulped down huge amounts of low-nutrient didymo with their meals.
"They had guts that were full of didymo. It looked like mats of cotton," said Biggs, who works for the country's National Institute of Water and Atmospheric Research.
In those areas, the number of trout has dropped 75 percent since the blooms of didymo began less than two years ago.
A publicity campaign has heightened didymo's profile in New Zealand and urged the public to take measures to prevent its spread. In North America, though, didymo is hardly familiar.
"It's totally off the radar screen," said Max Bothwell of Environment Canada, a federal agency.
Bothwell watched as didymo spread across Vancouver Island, where the first large-sized blooms showed up in the late 1980s.
The outbreak has died down in recent years, but scientists are still unsure about what triggered it.
The alga is native to parts of North America but typically doesn't erupt in the kind of nuisance blooms that have been seen in recent years.
"Something's going on," said Spaulding. "This isn't normal."
Didymo is tough and clings stubbornly to rocks when river flows are steady. It's often washed away in heavy flows.
When it does break off the rocks, it floats downstream. The slippery, gray tufts have been compared to wet toilet paper -- an unappetizing sight.
When didymo showed up outside Vail, Colo., people called authorities to report there was sewage in the water, Spaulding said.
So not only does the alga pose potential problems for the function of the stream, it also poses an aesthetic problem for anglers, who also have to deal with tangles of didymo on their lines, and other water recreationists, she said.
And when anglers begin to stay away from rivers for that reason, didymo poses an economic problem for communities that rely on fishermen who stay in hotels, eat at restaurants and buy groceries.
Scientists believe didymo spreads from river to river primarily by anglers, boaters and other people who move from one area to the next. Researchers in New Zealand recently found that the alga can survive for 40 days out of the water on a piece of equipment, Spaulding said.
Leah Elwell, conservation coordinator for the Federation of Fly Fishers in Livingston, said anglers should do the same thing they do to prevent the spread of other non-native species: check their gear before they leave an area and pick off any muck, clean gear thoroughly with a disinfectant and allow it to dry completely before using it again.
Even though there is still much to learn about didymo and its potential effects, it behooves the public and land managers to take it seriously and take measures to prevent its spread, said those at the conference.
"We can't afford to play this Russian roulette at this point," Biggs said.
Slimy algae draws scientists to Bozeman
=================================================
BOZEMAN Scientists from around the world are gathering in Bozeman today, for a conference on a slimy algae that is taking over streams in North America, New Zealand and Europe.
The algae, commonly called didymo, creates thick stalks that can clog canals and intakes and make it difficult for bugs, nymphs and fish to survive.
Outbreaks can extend for miles. In some places, it's considered an invasive species.
In Montana, major outbreaks have occurred on the East Boulder River south of Big Timber and the Kootenai River in northwest Montana.
Scientists are gathering at the conference to share information about didymo and discuss how to control it.
They plan to tour the outbreak on the East Boulder River tomorrow.
Copyright 2006 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.