Monitoring staff at the Susquehanna River Basin Commission have documented the second occurrence of the aquatic invasive species Didymosphenia geminata (didymo or “rock snot”) in the Susquehanna basin in the West Branch of Pine Creek, Potter County on October 16.

Didymo is a highly invasive algae that has caused ecological harm in many high profile instances worldwide. The massive blooms and mats resulting from the spread of didymo have the potential to choke aquatic life in the basin’s high quality, cold water streams and rivers.

“The Commission takes very seriously one of its core functions of monitoring the health of the Susquehanna Basin’s aquatic ecosystems,” said SRBC Executive Director Andrew Dehoff. “The second discovery of didymo in the basin causes concern with regards to the potential threat it poses to the sensitive habitats found within our more pristine waters of the basin.”

The first occurrence of didymo in the Susquehanna basin was documented by Department of Environmental Protection biologists in June in the main stem of Pine Creek in Lycoming County near Waterville, Pa.

Prior to that, such occurrences were documented in the Upper Delaware Watershed in Pennsylvania and New York as well as in several watersheds in southwestern Pennsylvania, western Maryland, and portions of West Virginia.

Anglers, boaters, or anyone coming into contact with an infected waterway can unknowingly spread this microscopic alga, which can cling to fishing gear, waders, boots, and boats.

Studies indicate that didymo can survive outside of a stream in a cool, dark, damp environment for at least 40 days, and only one cell is needed for it to spread. Those coming into contact with an infected waterway are encouraged to disinfect their gear to prevent further spread.

To find out more about didymo, the threats this aquatic invasive species poses to the Susquehanna basin, and detailed information on disinfection procedures, please visit the Fish and Boat Commission’s didymo information webpage and the Pennsylvania Sea Grant’s didymo information webpage.

11/11/2013