Bad algae found in premier trout stream

By Candace Page
Free Press Staff Writer

August 7, 2007
Invasive didymo -- the disgusting, potentially destructive algae commonly called rock snot -- was found last week in the Batten Kill, Vermont's most famous trout stream.

State biologists announced Monday they found a small amount of the algae late last week in the southern Vermont river. They also confirmed that a two-mile-long algae bloom last year on the Batten Kill in New York state was didymo. That bloom has not reappeared this year.

When didymo blooms in dense clumps, it can decimate a river's insect population, making it difficult for trout and other fish to find enough to eat.

"This is unfortunate because we are right in the midst of trying to restore the Batten Kill to its former glory," fishing guide Lawton Weber said Monday, referring to restoration efforts on the trout stream, where brown trout numbers dropped dramatically in the mid-1990s.

Biologists say they are not certain what effect didymo will have in Vermont rivers. The algae prefers cold, clear water. In some places, including one South Dakota trout stream, it has multiplied explosively. In others, it has had much less effect.

The Batten Kill is the third Vermont river where didymo has been discovered. The algae had not been identified in New England until last month, when Weber spotted large clumps in the upper Connecticut River. Soon, two didymo infestations were found in the White River as well.

Any further losses of trout in the Batten Kill would be a blow to anglers across the country who treasure the river for its population of wild brook and brown trout.

"The Batten Kill prominently stands out as the state's most famous trout stream and is considered by many anglers to be one of the most technically challenging streams to fish," the state's Batten Kill Trout Management Plan noted last year.

"Extending back to at least the 1850s when Manchester emerged as a resort center, the Batten Kill began attracting anglers from distant locations. Over the next 100 years its reputation of being one of the United States' premier trout streams continued to build," the plan said. In a 1998 poll of Trout Unlimited members, the river was named the tenth best stream in the country.

The Batten Kill is a favorite spot for tubing, canoeing and kayaking as well as fishing. A number of commercial outfitters lead trips on the river in all those sports.

Weber said the heavy use of the Batten Kill may make it more difficult to keep the algae from spreading, since wet boats can transport the algae if they are not disinfected before they are carried from downstream to the beginning of a run somewhere upstream.

Scientists from the Agency of Natural Resources inspected seven locations on the Batten Kill last week, finding didymo in one spot, near the New York border.

Agency Secretary George Crombie said Vermont will attend an international conference on didymo later this month in Montreal to seek a regional response to didymo with New Hampshire and New York.

Large blooms of didymo look and feel like wads of cotton. When water levels recede, didymo in dried masses can resemble rotting cardboard, the agency said.

Contact Candace Page at 660-1865 or cpage@bfp.burlingtonfreepress.com