An invasive form of algae that has been spreading through waters of the eastern United States is now confirmed in West Virginia. Samples of a particular form of algae taken from the Elk River near Webster Springs are now confirmed to be Didymo. Didymo is a short for Didymosphenia geminate.
"Thanks to some sharp-eyed anglers, we were able to get in there and take some samples and confirm it was didymo,” said DNR Warmwater Fisheries Chief Brett Preston.
More commonly known to anglers as "Rock Snot", the algae can form huge mats on the water branching off from a stalk that forms on the substrate of rocks in clear, cool, well-oxygenated streams.
"It can have some ecological impacts because of smothering invertebrates, particularly aquatic insects where it forms really thick mats,” said Preston.
It can also be a nuisance to anglers by constantly building up on fishing line, lures, and covering up potential fishing water.
"High flows tend to break this stuff up, so it doesn’t necessarily persist for a real long time in any one location," said Preston. "But obviously the concern is that it could spread."
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| Neighboring Maryland has installed disinfection stations to combat didymo spread. Photo: Cumberland Times-News |
That spread is typically traced down to poor maintenance of fishing gear, particularly felt soled waders. The DNR has issued a series of recommendations to disinfect and wash waders, fishing tackle, and even boat surfaces before moving to another waterway. The state of Maryland has actually installed disinfecting stations on the Gunpowder River and some other popular trout waters to enable anglers to clean their boots before departing. Similar stations are planned for the popular Savage River in Maryland. So far West Virginia has not installed such washing stations, but Preston says they are considering the idea that uses a five-percent salt solution to remove the fungal matter from boot soles.
"We’re just encouraging folks if you’re up there fishing to minimize the transport of plants and critters from one body of water to another to take the time to clean your gear as best you can,” said Preston.
So far the discovery is isolated to a stretch of the Elk River eight miles up stream and eight miles downstream of Webster Springs. Didymo has been a problem in western US trout streams for several years. More recently it’s been discovered in wasters of the northeast and Mid-Atlantic States.


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