Here's the press release from the State of Pennsylvania:


Zebra Mussel Found on Susquehanna River at Conowingo Dam in Maryland

Nine-MileLongLake Stretches Into Pennsylvania


HARRISBURG, Pa., Nov. 24 /PRNewswire-USNewswire/ -- Environmental Protection and Fish and Boat Commission officials have confirmed the discovery of a zebra mussel at the Conowingo Hydroelectric Dam in Maryland; the first time the Driessena polymorpha has been found in the lower Susquehanna River.


The mussel, about a half inch in size, was found inside a water intake at the hydroelectric plant while monitoring juvenile shad migration on the river. It had not yet attached itself to the intake structure.


The nine-mile lake behind the Conowingo Dam stretches into Pennsylvania for five miles. No other zebra mussels have been found in the lake at this time.


"Controlling zebra mussels has cost more than $1 billion since they were first discovered in the Great Lakes in 1988," said DEP acting Secretary John Hanger. "It will require constant vigilance by fishermen, boaters and others who use our waterways to keep these invasive creatures out of the Susquehanna River and its tributaries."


Zebra mussels pose serious threats because of their potential to plug industrial and public water supply intakes that draw from infested waters. Zebra mussels also disrupt aquatic food chains by filtering out the microscopic plankton upon which fish and other aquatic organisms rely. One zebra mussel can filter more than a quart of water each day.


Further, the mussels have created new pathways for diseases like Type E (Avian) Botulism in the Great Lakes, causing further damage to the Great Lakes' ecosystem.


"The introduction of invasive species like zebra mussels can have a substantial and lasting impact on the balance of aquatic life in a waterway," said Doug Austen, Pennsylvania Fish and Boat Commission's executive director. "The best thing anglers and boaters can do is to disinfect boats, trailers, boots and gear before entering a new body of water."


Adult zebra mussels can be found in other Pennsylvania waters, including Lake Erie, the Ohio River and lower portions of the Allegheny and Monongahela rivers. The mussels have also been reported in Edinboro and Sandy Lakes in northwestern Pennsylvania, as well as upper French Creek in Crawford County and Cowanesque Lake in Tioga County. The mussels have also been introduced into diving quarries throughout the commonwealth.


The zebra mussel is native to the Black and Caspian seas region of Eastern Europe. They were introduced to North American waters when ocean-going ships released infested ballast water into the Great Lakes.


The Pennsylvania Zebra Mussel Monitoring Network, which is sponsored by DEP, Pennsylvania Sea Grant and the National Oceanic and Atmospheric Administration's Coastal Zone Management Program, works to help slow the spread of invasive mussels in the commonwealth's rivers, streams and lakes.


For more information on zebra mussels, visit the Pennsylvania Sea Grant invasive species Web site at www.pserie.psu.edu/seagrant/publications/ais.htm.

CONTACT:
Tom Rathbun
(717) 787-1323







SOURCE Pennsylvania Department of Environmental Protection

What that release doesn't mention is it was a single mussel, with no bysal thread, apparently sucked against an impingement tray. Whether it was live or dead has been near impossible to sift out of the dozens of press releases. Thanks for putting this up Bob, I may try and find another one or two and add to this topic.

Let's hope against hope that it's a lone stray and not the first soldier in an invasion.

What that release doesn't mention is it was a single mussel, with no bysal thread, apparently sucked against an impingement tray. Whether it was live or dead has been near impossible to sift out of the dozens of press releases. Thanks for putting this up Bob, I may try and find another one or two and add to this topic.

I hope so too. The nuisances are established here in the Tennessee and Cumberland now.

So, did they kill it?

It was sent to a lab.

It was sent to a lab.

I hate to be a downer but where there's one there are more. You can count on it. These damn things (in the veliger stage) are like the fictional nanoprobes of Star Trek.

That's really a shame, I grew up fishing on that river...guess it will never be the same again...

The company I work for, NORMANDEAU ASSOCIATES INC., found all of the zebra mussels that have been found to date. Sorry to be the the one that has to break the BAD news, but the Zebra Mussel that was found at Conowingo Dam was not the only one found in the lower Susquehanna River. There was another single mussel found at Glen Cove marina under a pontoon boat that was being stored there for the winter. Also four more were found at the muddy run pump storage lake. Peach Bottom has been checking for these creatures for as long as I know. Any question, please feel free to contact me and I will point you in the right direction.

Mike Martinek
Normandeau Associates, Inc
Drumore, PA