Rock snot oozes ever closer

Above: Water shoes, anyone? Didymo warning on a pole near the Shandaken Tunnel at the Esopus Creek. Blooms of the noxious algae already coat the bottom of the creek. Photo by Daniel Case on Wikimedia Commons, used under Creative Commons license.

It's been awhile since we've reported on rock snot (also known as the noxious microscopic algae, didymo, once described on these pages as having as much visual charm as a wad of wet toilet paper), but it's back in the news in a big way.

WNBC-4 is reporting that didymo has been found in the Delaware River as far north as Callicoon, in Sullivan County.

Scientists in the past two weeks have discovered the algae from the Dingmans Ferry bridge in the Gap stretching about 100 miles north to upstate New York, where the river splits in its western and eastern branches.


"It might go all the way to Trenton," said National Park Service biologist Rich Evans.

The ecological threat cannot be understated, according to the Delware River Basin Commission's aquatic biologists who told the River Reporter last week

“We knew Didymo occurred in the river,” Dr. [Erik] Silldorff said, “but the spatial extent and intensity of this bloom is alarming given its potentially detrimental effect on ecosystems and the ease in which it can be spread to nearby tributaries.”

Didymo blooms can crowd and kill other beneficial and ecosystem-balancing algaes in riverbeds and can be easily spread from river-to-river on fly fishing equipment, which is of particular concern right now, during trout season. For more information on rock snot in the Delaware River watershed, head over to the Delaware River Basin Commission.