An invasive algae has been confirmed in the Lower Mountain Fork River in southeastern Oklahoma that threatens the popular trout fishing stream.
Called didymo, the algae grows on rocks and can destroy insects that trout feed on by outcompeting native algae that the bugs rely on.
There are streams in New Zealand that are completely coated in didymo where the trout fishing was ruined, said Curtis Tackett, aquatic nuisance biologist for the Oklahoma Department of Wildlife Conservation.
Didymo also is called rock snot, although Tackett said that is not an appropiate nickname for it.
“It’s not a very slimy, slippery algae like most are,” he said. “It’s more like wet toilet paper, the texture of it. It likes cold, flowing water that is high in oxygen. The Lower Mountain Fork is perfect for it.’’
This is the first time the species has been found in Oklahoma. Tackett theorizes it probably was transported to the Lower Mountain Fork River on an angler’s gear who was fishing in Arkansas or Missouri on a stream with the algae.
There is no health threat to humans. Most of the colonies confirmed of didymo in the Lower Mountain Fork River are small and isolated.
State wildlife officials are hoping it stays that way. But they admit it could threaten the pristine stream – considered Oklahoma’s crown jewel of trout fishing – if it spreads.
“We are hoping it doesn’t,” Tackett said. “It’s a pretty big concern.”
There are no chemical treatments to kill it.
“The best thing we can do is provide information to anglers and let them know how they can slow and stop the spread of it,” Tackett said.
The algae is easily snagged and brought it on a hook.
Tackett said it would help if anglers on the river would use rubber bottom sole waders instead of felt bottom waders, because the didymo will more easily attach to the felt waders. But he admits many anglers will be reluctant to do so.
However, he encourages anglers to take the following precautions to help prevent the spread.
1.) Before leaving the river or stream, remove all clumps of algae and look for hidden fragments.
2.) Soak and scrub all gear for at least one minute in a two percent bleach solution, or five percent salt solution, or simply use hot water and dishwashing detergent.
3.) If cleaning is not practical then after the gear is completely dry wait at least 48 hours before contact with another water body.
4.) Consider keeping two sets of wading boots, and alternate their use between cleaning and drying.
5.) Avoid wading through colonies of the algae. Breaking up the material could cause future colonies and blooms to occur further downstream.