State law combats spread of didymo

State law combats spread of didymo

February 21, 2011

Didymo blooms form in stages. During stage 1, didymo looks like small cotton balls attached to submerged river rocks.

In an effort to curb the spread of aquatic invasive species in Vermont rivers, the Vermont legislature has enacted, and the Governor signed into law, a ban on use of felt-soled waders in Vermont waters effective April 1, 2011. Felt-soled waders have been strongly implicated in the spread of several invasive species including didymo, as well as New Zealand mudsnail and Myxobolus cerebralis, the parasite that causes whirling disease in trout.

What is didymo?

Didymo is the common name for Didymosphenia geminata, an invasive freshwater diatom species (microscopic algae). Didymo was found in the White River in July 2007, and has formed extensive ‘blooms’ on the bottom of the river’s bed in Stockbridge and Bethel during the summer months. These blooms can smother aquatic life forms such as macroinvertebrates (aquatic insects), native algae, and other organisms. Additionally, the physical appearance of the bloom is aesthetically unpleasing, and can reduce the recreational values of a waterbody.

Don’t spread didymo!

Although there is no known method of removing or killing the algae once it is in the river, we can stop it from spreading! Simply CHECK, CLEAN, and DRY each time you use the White River.

Where can I get more information?

In addition to maintaining a Didymo Information page on our website, the WRP is working to raise awareness about didymo in the White River watershed by distributing an informational brochure to fishing license agents and by posting informational signs at public access sites.

During stage 2, didymo begins to cover the entire surface of submerged rocks. Stage 3 is pictured on the homepage.

You can help spread the word by adopting a river access site and maintaining the posted informational signs. Contact us to get involved!