Did you know about Didymo?
Rock Snot, Algea Lugee’s whatever you want to call it, Didymo is the grossest slippery invasion of freshwater rivers. Didymosphenia geminate, is easier spread than said and way more difficult to get rid of than just popping a mucinex. This species of diatom produces nuisance growths in rivers and streams. Didymo, which is a type of single-celled algae, spreads by attaching itself to fishing equipment, waders, boats, and just about anything else that has come in contact with Didymo-infected water. Didymo has been found in the Elk River in the Webster Springs area following reports from anglers. So we need to be on the lookout for Didymo in WV!
It’s “snot” what it looks like? It looks like toilet tissue stuck in between river rocks but feels allot like wet cotton. It’s not nearly as slimy as it looks. As Didymo fastens itself to rocks in water beds it eventually chokes out everything else that may live there. It’s generally brown, tan or yellow and can grow to
up to eight inches thick.
The following methods have been recommended to help prevent the spread of Didymo:
- Check: Before leaving the river, remove all obvious clumps of algae and look for hidden clumps. Leave them at the site. If you find clumps later don’t wash them down the drain, treat them with the approved methods below, dry them and soak them in bleach for at least 4 hours.
- Clean: Soak and scrub all items for at least one minute in either hot (60°C) water, a 2% solution of household bleach, antiseptic hand cleaner or dishwashing detergent.
- Dry: If cleaning is not practical (e.g. livestock, pets), after the item is completely dry wait an additional 48 hours before contact or use in any other waterway.
Absorbent items require longer soaking times to allow thorough penetration into the materials. Felt-soled waders, for example, are difficult and take time to properly disinfect. Other absorbent items include clothing, wetsuits, sandals with fabric straps, or anything else that takes time to dry out. The thicker and denser a material, the longer it will require for adequate disinfection. Err on the side of caution. Bleach solutions are not recommended for absorbent materials.
- Hot Water: Soak items for at least 40 minutes in very hot water kept above 140°F (hotter than most tap water).
- Dishwashing Detergent and hot water: (‘Green’ products are less effective and not recommended for disinfecting): soak for 30 minutes in a hot 5% detergent/water solution kept above 120°F.
A simple, portable DISINFECTION KIT might include:
•Large trash can and/or medium sized Rubbermaid-type bin for soaking wading boots
•Large stiff bristle brush for scrubbing
•Spray bottle(s) or herbicidal pump spray can(s)
•Graduated cylinder or measuring cup
•5% detergent solution and/or 2% bleach Solution
Felt Soled Boots…New Zealand, Alaska, Maryland and Vermont have banned anglers from wearing felt-soled boots. Orvis, a leading U.S. manufacturer of fly-fishing equipment, has started selling more rubber-soled boots than felt-soled to do their part in the riddance of this menace.
Do your part and inspect any items that have come in contact with river water. Please contact the DNR fisheries biologist at the nearest district office to report possible Didymo outbreaks.
Other sources of information on Didymo: