Aquatic Nuisance - Didymo

Didymo (Didymosphenia Geminata)

Didymo/Rock Snot Image

    Where did it come from?
  • Originates in Europe, Asia and parts of North America.
  • Where can it be found in South Dakota?
  • Rapid Creek in Pennington County in the Black Hills
  • What does it look like?

  • It is tan, light brown, and whitish that has clumps of ropy strands, a rough cottony feel and fibrous.
Why is Didymo a problem?
  • It can form in large masses driving out food sources for other plants and animals. It may be a leading cause in the decline of Brown Trout in Rapid Creek.
How is Didymo spread?
  • Didymo can stick to anything (boats, fishing gear, and wading gear) it touches and be transported without the proper removal.

Check out Aquatic Nuisance Species Prevention on ways to prevent the spread of Aquatic Nuisance Species

Didymo links
Digital Frontier Fact Sheet on Didymo
Pictures of Didymo
South Dakota Didymo Distribution

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