News Flash from plants’ photosynthetic cousins: Didymosphenia geminata, one of the fastest spreading single-celled algae strains in the world has struck again, this time in the waters of the Esopus Creek in Shandaken, New York.

Didymo, also known as Rock Snot, has been a growing concern for biologists in recent years. It first caught the eye of the scientific community in New Zealand in 2004. It appeared as a non-native species on South Island and within a matter of just a couple years spread rapidly and infested hundreds of South Island’s rivers and streams.

There was a time when Didymo was considered to be a harmless, native North American algae strain, but now it has become quite a force to reckon with. Aside from the alarming pace with which the plant reproduces, it also grows in immensely thick layers that can clog up entire rivers, clogging crucial water supplies to cities and farm lands. It can spread so voraciously that it covers entire bodies of water from “bank to bank” cutting off oxygen and sunlight to any aquatic life present.

The most recent infestation has taken place in New York about 120 miles North of Manhattan. Officials have been screening the waters of New York for Didymo regularly and cite that the infestation was not present during the recent inspection done last fall. Rock Snot has the potential to dam up the city’s entire upstate drinking water system, as well as the country’s most popular fly-fishing streams Beaverkill and Willowemoc.

For years, scientists like Sarah A. Spaulding, an ecologist with the United States Geological Survey have studied the adverse affects of unchecked Didymo growth in the waters of the world. From her studies we know that one of the leading causes of new Didymo infestations is accidental transportation of the algae by anglers who do not properly clean, sterilize, and dry their fishing equipment. According to Spauling, Didymo can survive outside water for a day, and up to 90 days in a damp, stagnant area like the trunk of a car.

“As of yet, there are no known ways to eradicate Didymo once it [is] established” said Leslie J. Surprenant, the New York State invasive species management coordinator. However, there is hope that if the fishing community can be educated about the harms of Rock Snot and measures to prevent the spread of it we can suppress the onset of more infestations and begin to purge our waters of this destructive algae.

Discussion question: What do you think the fishing industry can do to prevent the spread of Didymo?

News Article: http://www.nytimes.com/2009/06/16/science/16invasive.html?_r=1&ref=earth

Link to study by Sarah A. Spaulding on the adverse effects of Didymo: http://www.epa.gov/region8/water/didymosphenia/