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For Release: Monday, July 30, 2012

Invasive Algae Found In Additional Fishing Waters

The invasive algae didymo (Didymosphenia geminata) was confirmed in a popular fishing stream in the Greene County town of Lexington, the New York State Department of Environmental Conservation (DEC) announced today.

Samples taken by the U.S. Geological Survey and examined by DEC have confirmed that didymo is present in the Schoharie Creek about 1.8 miles east (upstream) of the hamlet of Lexington. This is the latest recorded incident of this aquatic nuisance species, also called "rock snot," in New York State.

Upper Schoharie Creek is a popular trout fishery and the discovery of didymo here is particularly troubling given its proximity to other trout streams and the tendency of anglers to fish multiple streams during the course of a day or weekend. Porous materials such as neoprene waders and felt soles used by wading anglers are prime suspects in the spread of didymo among streams.

Didymo cells can produce large amounts of stalk material that forms thick mats on stream bottoms. During blooms, these mats may completely cover long stretches of stream beds. It can alter stream conditions, choking out many of the organisms that live on the stream bottom, potentially causing a ripple effect up the food chain affecting trout and other fish. "Mats" of didymo can choke out organisms that live on stream bottoms.

Once introduced to an area, didymo can rapidly spread to nearby streams. Anglers, kayakers, canoeists, boaters and jet skiers can all unknowingly spread didymo by transporting the cells on boats and other gear.

Check, Clean, Dry

Those who witness or suspect the presence of didymo in state waters are advised to contact DEC with the location so that samples can be taken to document and monitor the algae's spread. DEC continues to urge anglers and other water recreationists to "check, clean and dry" to prevent the introduction and spread of didymo.

Check - Before leaving a river or stream, remove all obvious clumps of algae and look for hidden clumps. Leave them at the affected site. If you find any later, do not wash them down drains; dispose all material in the trash.

Clean - Treatment varies depending on what needs to be cleaned. Be sure that the solution completely penetrates thick absorbent items such as felt-soled waders and wading boots.

Dry - If cleaning is not practical, after the item is completely dry to the touch, wait an additional 48 hours before contact or use in any other waterway. Check thick, absorbent items closely to assure that they are dry throughout. Equipment and gear can also be placed in a freezer until all moisture is frozen solid.

NOTE: If cleaning, drying or freezing is not practical, restrict equipment to a single water body.

For more information on didymo, visit the DEC website.

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