Working in the Susquehanna River below Conowingo Dam this week doing benthic trawls, seining, and snorkeling. Lots of time in the water and we've now discovered what isn't a total surprise. Zebra mussels are below the dam. They were only recently found just above the dam. About a dozen live specimens were found scattered about a 4 mile long by 1 mile wide stretch of river. I'm holding out hope that the extreme conditions caused by a hydropeaking reservoir are too harsh for them to gain a hold and survive before the tidal fresh section that is the extreme upper part of the Chesapeake Bay and Susquehanna Flats.
Zebra mussels - Maryland
Started by
Guest_ashtonmj_*
, Jul 08 2010 07:49 PM
15 replies to this topic
#2
Michael Wolfe
-
- Board of Directors
-
- North Georgia, Oconee River Drainage
Posted 08 July 2010 - 07:55 PM
OK, I didn't know my Chesapeake geography and had to look that dam up... so now I see where it is and it makes me ask a dumb question... how did the zebra's get above the dam anyway? What was the vector by which they were introduced?
Either write something worth reading or do something worth writing. - Benjamin Franklin
#3
Guest_Lotsapetsgarfhts_*
Guest_Lotsapetsgarfhts_*
-
- Guests
Posted 09 July 2010 - 06:41 AM
OK, I didn't know my Chesapeake geography and had to look that dam up... so now I see where it is and it makes me ask a dumb question... how did the zebra's get above the dam anyway? What was the vector by which they were introduced?
The larvae go through a free swimmng stage, they can be introduced through bilge water even from small boats then there are live well and bait bucket dumps. Then there is also the possibility they came off the hull of a fishing boat. It is believed they came to the Great Lakes in larval form in ballast water.
#4
Michael Wolfe
-
- Board of Directors
-
- North Georgia, Oconee River Drainage
Posted 09 July 2010 - 06:59 AM
The larvae go through a free swimmng stage, they can be introduced through bilge water even from small boats then there are live well and bait bucket dumps. Then there is also the possibility they came off the hull of a fishing boat. It is believed they came to the Great Lakes in larval form in ballast water.
Yes, I knew that, but I am unaware of any Russian boat traffic that goes up beyond a dam on the Chesapeake. I know that lots of water in the US is connected in some way or another to the Great Lakes, but not here right? Is it believed that these were transported by pleasure boaters? It's just not immediately obvious to me how this happened.
Either write something worth reading or do something worth writing. - Benjamin Franklin
#5
Guest_ashtonmj_*
Guest_ashtonmj_*
-
- Guests
Posted 09 July 2010 - 07:15 AM
Michael you're correct, the most often thought of vector, large commercial vessels, is not really pertinent to this situation; however there is substantial traffic of large vessels up to Baltimore. They can be transported by recretional boats via bilge or livewell water. For example, several years ago an infestation showed up in a Virginia quarry lake. So most likely at some point in recent years they were brought to the Susquehanna River (upstream of dam) by a recreational boat. Their veligers have likely dispersed downstream through the dam turbines or spillways. Absorbant sufaces (wader felt) that also come into contact are of concern.
#6
Michael Wolfe
-
- Board of Directors
-
- North Georgia, Oconee River Drainage
Posted 09 July 2010 - 07:38 AM
Michael you're correct, the most often thought of vector, large commercial vessels, is not really pertinent to this situation; however there is substantial traffic of large vessels up to Baltimore. They can be transported by recretional boats via bilge or livewell water. For example, several years ago an infestation showed up in a Virginia quarry lake. So most likely at some point in recent years they were brought to the Susquehanna River (upstream of dam) by a recreational boat. Their veligers have likely dispersed downstream through the dam turbines or spillways. Absorbant sufaces (wader felt) that also come into contact are of concern.
Well that is sad and sobering... I liked blaming dirty russian neo-capitalists for our problems... it's no fun to have to look in the mirror and talk about fishing boats (which I actually don't own) and waders (which I do)... guess that means we are going to have give us waders!?! Good thing I live in Georgia.
Either write something worth reading or do something worth writing. - Benjamin Franklin
#7
Guest_darter1_*
Guest_darter1_*
-
- Guests
Posted 09 July 2010 - 07:54 AM
Matt,
We (PFBC) have been in the Upper Conowingo pool and above quite a bit lately. We will keep our eyes open. I remember them being found a few years ago, but haven't heard much since. Thanks for the update.
Tim
We (PFBC) have been in the Upper Conowingo pool and above quite a bit lately. We will keep our eyes open. I remember them being found a few years ago, but haven't heard much since. Thanks for the update.
Tim
#8
Guest_ashtonmj_*
Guest_ashtonmj_*
-
- Guests
Posted 09 July 2010 - 12:28 PM
Tim, I believe it was actually someone from your agency that found the first specimen in winter of 2008. Working on a press release now...
Michael, Felt soles are definately on the way out. Vermont just passed a ban, other states are working on them, and regardless at least two manufacturers have voluntarily agreed to stop selling them. We've been using Simms Headwaters with Aquastealth soles for 3 years. Considering the mileage and daily use we put on these boots, 3 years is a lifetime, plus the soles have been just as good as felt on slippery surfaces. They come with studs too, so any arguements that they are not as safe as felt or studded felt are essentially wasted breath.
Michael, Felt soles are definately on the way out. Vermont just passed a ban, other states are working on them, and regardless at least two manufacturers have voluntarily agreed to stop selling them. We've been using Simms Headwaters with Aquastealth soles for 3 years. Considering the mileage and daily use we put on these boots, 3 years is a lifetime, plus the soles have been just as good as felt on slippery surfaces. They come with studs too, so any arguements that they are not as safe as felt or studded felt are essentially wasted breath.
#9
Guest_Lotsapetsgarfhts_*
Guest_Lotsapetsgarfhts_*
-
- Guests
Posted 09 July 2010 - 01:34 PM
I have begun seeing them in some of the reservoirs here that are pretty far away from Lake Erie, and I am sure they either came in water from live wells, bilge water, or directly off recreational boats. The good news if there is any though is they do not seem to do very well everywhere. When they first became abundant here, I collected some rocks covered with them for the Aquarium at the Zoo (this was not illegal at the time) and they could not keep them alive. They ended up glueing the dead mussel shells back on the rocks for their display.
From the sounds of things they are not doing very well in the Susquehanna River above or below the dam. Here where you find them they are usually found in large numbers.
From the sounds of things they are not doing very well in the Susquehanna River above or below the dam. Here where you find them they are usually found in large numbers.
#10
Guest_wargreen_*
Guest_wargreen_*
-
- Guests
Posted 10 July 2010 - 07:27 PM
Hmmn that is so interesting, has anyone figured out why they do well in some areas and not in others (this is really good news) is it predatory fish, other mussels, water parameters, etc?
I have begun seeing them in some of the reservoirs here that are pretty far away from Lake Erie, and I am sure they either came in water from live wells, bilge water, or directly off recreational boats. The good news if there is any though is they do not seem to do very well everywhere. When they first became abundant here, I collected some rocks covered with them for the Aquarium at the Zoo (this was not illegal at the time) and they could not keep them alive. They ended up glueing the dead mussel shells back on the rocks for their display.
From the sounds of things they are not doing very well in the Susquehanna River above or below the dam. Here where you find them they are usually found in large numbers.
Edited by wargreen, 10 July 2010 - 07:28 PM.
#11
Guest_ashtonmj_*
Guest_ashtonmj_*
-
- Guests
Posted 16 July 2010 - 06:54 PM
Zebra Mussels Now Established In Susquehanna River Below Conowingo Dam
DNR Asks Citizens to Help Stop the Spread of this Invasive Species
Port Deposit, MD (July 15, 2010) —
On July 6th, a team of biologists from the Maryland Department of Natural Resources’ (DNR) Monitoring and Non-tidal Assessment Division spotted several suspected zebra mussel adults for the first time in the lower Susquehanna River below the Conowingo Dam. These recent findings indicate that a population of this non-native, invasive mussel is established in this part of the Susquehanna. The first-ever sightings of zebra mussels in Maryland occurred in the lower Susquehanna River upstream of the Conowingo in November 2008.
“Most of the specimens were the largest I’ve ever seen, ranging up to 38 mm (almost 1-1/2 inches) in shell length, and they were probably three to four years old,” said DNR Biologist Ron Klauda.
Zebra mussels (Dreissena polymorpha) have caused over five billion dollars in damages and economic losses in North America since they were introduced into the Great Lakes during the 1980s. Based on studies conducted in the Hudson River Estuary, New York, the potential impacts of zebra mussels on the freshwater to slightly brackish portions of Maryland’s aquatic ecosystem could be substantial, with effects on all aspects of the food web from plankton to fish by outcompeting native species, filtering all available plankton and rapidly colonizing large areas.
“The good news is that, at least for now, the density of zebra mussels appears to be low,” said DNR Natural Resource Biologist Jay Kilian.
Boaters, anglers and other recreational water users who enjoy the lower Susquehanna River can help stop the spread of harmful zebra mussels to other Maryland waters by taking these simple precautions before launching and before leaving:
(1) Remove all aquatic plants and mud from boats, motors, and trailers, and put the debris in the trash.
(2) Drain river water from boat motors, bilges, live wells, bait buckets and coolers before leaving to prevent aquatic hitchhikers from riding along.
(3) Dispose of unused live bait on shore far from the water body or in the trash.
(4) Rinse boats, motors, trailers, live wells, bait buckets, coolers and scuba gear with high pressure or hot water between trips to different water bodies.
(5) Dry everything at least two days (preferably five days) between outings.
DNR urges boaters to do their part to stop the introduction and spread of zebra mussels and other invasive species in Maryland. Citizens who find what look like zebra mussels should seal them in a zip lock bag, put the bag in the freezer, record where and when they were found and report the find to DNR at 410-260-8615. For more information about zebra mussels and other invasive species in Maryland, call 1-877-620-8DNR or visit www.dnr.maryland.gov/invasives.
DNR Asks Citizens to Help Stop the Spread of this Invasive Species
Port Deposit, MD (July 15, 2010) —
On July 6th, a team of biologists from the Maryland Department of Natural Resources’ (DNR) Monitoring and Non-tidal Assessment Division spotted several suspected zebra mussel adults for the first time in the lower Susquehanna River below the Conowingo Dam. These recent findings indicate that a population of this non-native, invasive mussel is established in this part of the Susquehanna. The first-ever sightings of zebra mussels in Maryland occurred in the lower Susquehanna River upstream of the Conowingo in November 2008.
“Most of the specimens were the largest I’ve ever seen, ranging up to 38 mm (almost 1-1/2 inches) in shell length, and they were probably three to four years old,” said DNR Biologist Ron Klauda.
Zebra mussels (Dreissena polymorpha) have caused over five billion dollars in damages and economic losses in North America since they were introduced into the Great Lakes during the 1980s. Based on studies conducted in the Hudson River Estuary, New York, the potential impacts of zebra mussels on the freshwater to slightly brackish portions of Maryland’s aquatic ecosystem could be substantial, with effects on all aspects of the food web from plankton to fish by outcompeting native species, filtering all available plankton and rapidly colonizing large areas.
“The good news is that, at least for now, the density of zebra mussels appears to be low,” said DNR Natural Resource Biologist Jay Kilian.
Boaters, anglers and other recreational water users who enjoy the lower Susquehanna River can help stop the spread of harmful zebra mussels to other Maryland waters by taking these simple precautions before launching and before leaving:
(1) Remove all aquatic plants and mud from boats, motors, and trailers, and put the debris in the trash.
(2) Drain river water from boat motors, bilges, live wells, bait buckets and coolers before leaving to prevent aquatic hitchhikers from riding along.
(3) Dispose of unused live bait on shore far from the water body or in the trash.
(4) Rinse boats, motors, trailers, live wells, bait buckets, coolers and scuba gear with high pressure or hot water between trips to different water bodies.
(5) Dry everything at least two days (preferably five days) between outings.
DNR urges boaters to do their part to stop the introduction and spread of zebra mussels and other invasive species in Maryland. Citizens who find what look like zebra mussels should seal them in a zip lock bag, put the bag in the freezer, record where and when they were found and report the find to DNR at 410-260-8615. For more information about zebra mussels and other invasive species in Maryland, call 1-877-620-8DNR or visit www.dnr.maryland.gov/invasives.
#12
Guest_az9_*
Guest_az9_*
-
- Guests
Posted 13 September 2011 - 08:24 PM
Hmmn that is so interesting, has anyone figured out why they do well in some areas and not in others (this is really good news) is it predatory fish, other mussels, water parameters, etc?
My understanding is they don't do well in soft water as they need the carbonates of hard water to build their shells. Sounds plausible anyway.
#13
Guest_nativeplanter_*
Guest_nativeplanter_*
-
- Guests
Posted 14 September 2011 - 07:15 AM
Michael, Felt soles are definately on the way out. Vermont just passed a ban, other states are working on them, and regardless at least two manufacturers have voluntarily agreed to stop selling them. We've been using Simms Headwaters with Aquastealth soles for 3 years. Considering the mileage and daily use we put on these boots, 3 years is a lifetime, plus the soles have been just as good as felt on slippery surfaces. They come with studs too, so any arguements that they are not as safe as felt or studded felt are essentially wasted breath.
I have LLBean Aquastealth wading shoes. Unfortunately, I rather dislike them. They haven't been very stable for me on cobble/boulder streams and rivers in the Southeast. I was actually thinking of going back to felt and just bleaching them after each trip. Even if the bleach shortens the life of my wading shoes, I'd rather pay for new shoes than for knee repairs (been there before; really don't want to go back). I don't know if non-Southeast cobble/boulder streams have a different texture, but I really am nervous wearing what I have right now on rocks. Perhaps I'm clumsier than most, but I keep slipping and falling.
#14
Guest_nativeplanter_*
Guest_nativeplanter_*
-
- Guests
Posted 14 September 2011 - 09:22 AM
I did a little searching, and found this on a number of state governmental websites regarding disinfection for didymo:
Absorbent items -- require longer soaking times to allow thorough saturation. For example, felt-soled waders require:
Hot water -- soak for at least 40 minutes in hot water kept above 113° F (45° C) ; OR
Hot water plus detergent -- soak for 30 minutes in hot water kept above 113° F (45° C) containing 5% dishwashing detergent; OR
Freezing any item until solid will also kill didymo
I could certainly do this every evening (even if camping, I can heat water on the camp stove). Obviously, hopping between sites in the same day would require separate shoes. Would this strategy work for other issues like zebra mussels and whirling disease?
Absorbent items -- require longer soaking times to allow thorough saturation. For example, felt-soled waders require:
Hot water -- soak for at least 40 minutes in hot water kept above 113° F (45° C) ; OR
Hot water plus detergent -- soak for 30 minutes in hot water kept above 113° F (45° C) containing 5% dishwashing detergent; OR
Freezing any item until solid will also kill didymo
I could certainly do this every evening (even if camping, I can heat water on the camp stove). Obviously, hopping between sites in the same day would require separate shoes. Would this strategy work for other issues like zebra mussels and whirling disease?
#15
Guest_Newt_*
Guest_Newt_*
-
- Guests
Posted 14 September 2011 - 10:14 AM
Is there not a bleach treatment protocol for didymo? We use bleach to disinfect waders and other equipment between ponds in herp studies, to prevent transmission of ranavirus and Batrachochytrium. It's pretty quick (we have to hit ten or twelve ponds in a day, so 30 or 40 minute disinfections are not feasible).
#16
Guest_captmicha_*
Guest_captmicha_*
-
- Guests
Posted 04 July 2012 - 09:17 PM
Matt, can I ask what group you work with?
Edited by captmicha, 04 July 2012 - 09:17 PM.
0 user(s) are reading this topic
0 members, 0 guests, 0 anonymous users
NANFA Youtube Channel 
