Education, not eradication, for 'rock snot'
'Horse is already out of the gate' in case of invasive algae
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By Dennis Jensen Rutland Herald - Published: July 14, 2007
WATERBURY — Biologists and government officials are hoping an informational campaign will help to stop the spread of didymo, the aquatic nuisance algae that has been found in two Vermont rivers in the past couple of weeks.
Vermont officials this week confirmed the presence of large concentrations of didymo in the White River. Late last month, a Vermont trout fishing guide made the first discovery of the algae, which can eliminate trout habitat in the waters where it is found. It also has been found in the Connecticut River.
On Friday, more than a dozen biologists, government officials and others from Vermont and New Hampshire met to discuss ways to prevent the further spread of didymo, also called "rock snot," to other waterways.
Justin Johnson, the deputy commissioner of the Vermont Department of Environmental Conservation, said that fish and wildlife agencies from Vermont and New Hampshire will post warning signs on both sides of the Connecticut River, advising anglers, canoeists, kayakers and other users of the river about how to avoid transmitting the microscopic algae to other waters. Warning signs will also be posted along the White River.
"We're going to have signs available to inform people about how to make sure they clean their clothes and waders, their fishing gear, their boats and kayaks," he said. "The signs will let them know that didymo has been identified in the river and tell them what they can do to stop its spread."
In addition, Johnson said, both states will post a Web site that will provide even more information about the threat.
"By early next week, we will have a joint New Hampshire-Vermont Web site so people will be able to access information about didymo a bit more in depth and show how they can avoid its spread," he said.
Didymo leaves a thick, matted covering on rocks and vegetation that can eliminate the insect population of a river or stream. Wild trout feed heavily on these insects.
There is no known treatment for didymo infestation.
"The professional opinion of everybody at the meeting is that it cannot be eradicated," Johnson said. "Once it's there, it's there."
But Johnson stressed that that doesn't mean the aquatic nuisance can't be contained.
"The most important thing right now is to give people information so that they can do what they need to do to make sure we stop it from spreading," he said. "They can do that by keeping their gear clean and not transporting didymo."
Biologists this week confirmed that the algae has been found in two locations, six miles apart, on the White River in the towns of Royalton, Bethel and Stockbridge. The finding comes after last week's confirmation of didymo along the northern reaches of the Connecticut River.
The initial discovery of didymo was made by Lawton Weber, a fishing guide who lives in Underhill. Lawton is considered somewhat of an authority on the alien species.
Weber was invited to attend the meeting and said he urged the biologists and staff to consider closing off the main stretch of the White River.
"I said close the White River to recreation use until we get a handle on this, in terms of what other rivers might be infested," he said. "I said we should close just the main stem of the White. That would be the best way to alert the public. If we find that another river is affected, then we can open the White River back up."
Weber said ANR and Fish and Wildlife officials were not too keen on that idea.
"They were saying, 'It's unprecedented. We can't think of doing that,'" he said.
Johnson said, as far as the White River was concerned, "the horse is already out of the gate" so there was no point in closing the river to recreational use.
"I don't even know if we have the authority to do that and I'm not sure what it would achieve," he said "What we're really concerned with is giving people the information they need to avoid spreading it."
Meanwhile, based on evidence Weber has seen, he believes that the infestation of didymo in the White River is much worse than he imagined.
"The didymo in the White River actually looks more widespread, from Bethel downstream, than in the Connecticut River," he said.
Representatives from the Vermont Agency of Natural Resources; the New Hampshire departments of Environmental Services and Fish and Game; the Connecticut River Joint Commission; the White River Watershed Group and the U.S. Fish and Wildlife Service attended the meeting.
Contact Dennis Jensen at dennis.jensen@rutlandherald.com
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