Group finds three new 'rock snot' sites in state
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By PATRICK McARDLE Herald Staff - Published: January 13, 2009
ARLINGTON — The invasive algae didymosphenia geminate, commonly called didymo or rock snot, has been found in three new locations in Southern Vermont although no nuisance blooms have been seen, according to the Batten Kill Watershed Alliance.
The alliance's executive director, Vermont Rep. Cynthia Browning, D-Arlington, said on Monday that tests were done in the summer on eight sites along the Batten Kill and its tributaries.
Didymo cells were found in four of those sites, the Batten Kill in Manchester and Arlington, the West Branch River in Manchester and the Green River in Sandgate.
Browning said the results indicated that people using Vermont waterways should think about their habits, especially when they use more than one river or stream.
"When we're going into rivers and streams, we have to assume that didymo is there and that if we use another river, we don't want to bring it to the water where we are now," she said.
Browning said she expected that would not be an easy change for Vermonters who were used to using more than one body of water for activities such as fishing or canoeing with little concern about possible effects.
However, as reports of didymo sites throughout the state expand, it becomes more important to remind residents that boating and fishing equipment and gear, like felt-soled waders, need to be thoroughly cleaned with hot, soapy water when moving from one site to the next.
Didymo algae has been a particular concern for Vermont because so little is known about it. No one is certain how it travels from river to river or how to clean it out of a river where it's been found although didymo generally thrives in warmer, shallow rivers.
"It's obviously a concern for all waterways in Vermont as with any invasive species that's moving from one waterway to another," said Josh Gorman, watershed coordinator for the Vermont Department of Environmental Conservation in Bennington County.
In 2006, a didymo bloom was found on the New York side of the Batten Kill. The blooms are dull-colored stalks that stick to rocks and look like wet wool.
While didymo is not believed to be toxic to humans or fish, some states, including Tennessee and South Dakota, believe it has contributed to a decline in trout population. When it blooms, the algae forms "mats" that hinder the environment of the insect population. Environmental scientists believe that, in turn, decreases the trout population.
The blooms also look unappealing enough to have earned the popular term "rock snot," another concern for people in Arlington, where businesses have long relied on tourists drawn to the Batten Kill's scenic beauty.
"We like to keep the Batten Kill looking as good as it is," Browning said.
Didymo was found in Vermont in 2007 in the Batten Kill at West Arlington and the Connecticut and White rivers. Last year, the state identified didymo in the Mad River near Warren.
Browning said she had visited the White River in 2008 to see a didymo bloom and said it had a "slippery, gritty feeling."
The Batten Kill Watershed Alliance surveyed the river during the summer through an aquatic nuisance species grant secured by Arlington and Manchester through the Vermont Agency of Natural Resources.
Browning said the methodology had to be adjusted during the study when water sampling returned results that showed no algae. Scrapings from rocks were taken in September and sent to the Agency of Natural Resources' Water Quality Division environmental scientist Leslie Matthews in Waterbury.
Browning said the presence of didymo in the samples had only recently been confirmed.
However, the testing process hasn't yet provided any information about the length of time didymo has been present in the newly-identified sites, according to Gorman.
Browning said she expects more sampling and testing will be done this year.
Partners such as the Batten Kill Watershed Alliance have been important to state efforts, Gorman said, and he encouraged other communities to apply for grants and participate in efforts to prevent the spread of didymo.
For more information on didymo algae on the Internet, visit the Water Quality Division Web page at www.vtwaterquality.org/lakes/htm/ans/lp didymo.htm.
Contact Patrick McArdle at patrick.mcardle@rutlandherald.com.
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