From an e-mail sent on July 10th by Dr. Mel Zimmerman at Lycoming College in my home town of Williamsport, Pennsylvania:
Attached is a picture we took this morning from a sample above Waterville – coming to a watershed near you.
First record of the invasive diatom Didymosphenia geminata in the Pine Creek watershed, Lycoming County Pennsylvania.
Pennsylvania Department of Environmental Protection (DEP) Biologists have, as a result of routine monitoring, detected the presence of the invasive diatom Didymosphenia geminata, also known as Didymo, in the Pine Creek watershed, Lycoming County PA. Representative specimens were sent to The Academy of Natural Sciences of Drexel University where Dr. Marina Potapova confirmed DEP’s identification.
Living Didymo diatoms were obtained on June 18, 2013 from Pine Creek at a location upstream of Waterville in the vicinity of the Hamilton Bottom Canoe Access Area; Lycoming County. This represents the first evidence of this invasive diatom in this watershed. In fact, prior to this discovery no Didymosphenia geminata diatoms were known by DEP to exist in Pennsylvania waters except at verified infestations sites in the Youghiogheny River and the West Brach / mainstem of the Delaware Rivers.
All Water Quality professionals (and ALL anglers) should take precautions against spreading Didymo by properly cleaning and disinfecting aquatic gear prior to working in other waters. For more information, please visit PA Fish & Boat Commission website for a fact sheet and further guidance at:
You are encouraged to forward this notice to your Agency co-workers, fellow aquatic biologists and other Water Quality professionals. (and your fishing friends).
Tony Shaw | Water Pollution Biologist IV | Chief, Monitoring Section
Environmental Protection | Point & Non-Point Source Management
Rachel Carson State Office Building
400 Market Street | Harrisburg, PA 17105-8774
Phone: 717.787.5017 | Fax: 717.772.3249
Rock snot can basically take over the stream bottom, when it colonizes an area, there is room for nothing else to live. It can obliterate the environment where invertebrates live by covering it up. When trout spawn, the female clears a redd, but by the time the eggs hatch, if didymo is nearby, it will have recolonized the redd and the fry will be unable to escape. But, by that time, the eggs will have been smothered anyway.
Anglers and everyone using Big Pine Creek are strongly urged to take the necessary precautions to keep this from spreading. However, the pessimist in me, knowing there will be people visiting Pine Creek that are unaware of the presence of didymo, will most likely unknowingly carry it to other streams in the area. Some of the best trout streams in Pennsylvania – Big Fishing Creek, Spring Creek, Penn’s Creek, Slate Run, Little Juniata River, are all at risk. Please be extremely careful. Guess we’re going to have to start carrying Clorox and a bucket or large dishpan in our cars so we can disinfect our wading shoes and the neoprene feet on our waders when we fish different streams in the same day.