Quagga Mussels found in Deer Creek Reservoir

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*Must Decontaminate Boats at Deer Creek Reservoir*
*Five microscopic veligers found in water sample*
Starting immediately, you must decontaminate your boat before
you leave Deer Creek Reservoir in north-central Utah.
The requirement comes after DNA tests conducted by two laboratories found
microscopic juvenile quagga mussels-called veligers-in a water sample taken
at the reservoir.
Jordan Nielson, aquatic invasive species coordinator for the Division of
Wildlife Resources, says the discovery does not mean Deer Creek Reservoir
is infested with quagga mussels.
“We’ve found veligers in the past at other waters in Utah,” he says. “With
the exception of Lake Powell, mussel populations never established
themselves in the waters where veligers were found. We’re hoping that will
be the case at Deer Creek too.”
Nielson says quagga mussels usually do not reproduce in water that’s colder
than 50 degrees, so-even if there are adult mussels in the
reservoir-there’s currently little risk of the population expanding. That
could change, though, once the water starts to warm in the spring.
One item biologists and water managers are concerned about now is mussels
being carried to other waters in or on boats. That’s why DWR Director Greg
Sheehan signed an order on Jan. 15 that requires boats to be decontaminated
before leaving Deer Creek State Park. Upon leaving the park, boaters must
do one of two things:
Clean and drain their boat, on their own. After cleaning and
draining, a DWR or Utah State Park technician will place a tag on the boat
that indicates when it was cleaned and drained. The boat will not be
allowed to launch at another body of water in Utah until the boat has dried
long enough to kill any mussels that might be in or on it.
In the winter, boats must dry for at least 30 days. The drying time can be
as little as three days, though, if the temperature the boat is drying in
remains below 32 degrees Fahrenheit for at least 72 straight hours.
Have their boat professionally decontaminated. The service is
free.
A DWR or Utah State Parks technician will determine whether the boat needs
to be professionally decontaminated.
Nielson says the presence of veligers in the reservoir does not mean a
quagga mussel population has established itself there. “To establish
itself,” he says, “a quagga population needs adult mussels.”
Which raises a question: if there aren’t any adult mussels in the
reservoir, where did the juvenile mussels come from?
“This could be an isolated incident,” Nielson says. “For example, it’s
possible that the veligers made their way to the reservoir in or on a boat
that had been on a contaminated water. We’ll know a lot more after we and
our partners conduct further surveys this spring.”
*What’s next?*
This spring, the DWR and its partners, including Utah State Parks and the
Bureau of Reclamation, will take action to learn whether adult quagga
mussels are in the reservoir. That action includes:
Collecting and analyzing water samples.
Sending divers into the reservoir, to search for mussels.
Placing substrate samplers in the water. Adult quaggas attach to
these as they move through the water.
Surveying shorelines.
Water from the reservoir flows into the lower Provo River and then into
Utah Lake. Nielson says quagga mussel sampling work has been underway at
Utah Lake for years. “The sampling work will continue in 2015,” he says.
Starting this spring, biologists will also sample the lower Provo River.
Nielson says the middle Provo River, the section between Jordanelle and
Deer Creek reservoirs, is less at risk. “Quaggas can’t move upstream,” he
says. “The only way they could make their way to the middle Provo River is
if they were transported there on someone’s boots or fishing equipment.”
On Oct. 30, 2014, a Bureau of Reclamation (BOR) water quality sampling crew
collected water samples across Deer Creek. The water samples were later
analyzed by a BOR lab.
On Dec. 12, lab technicians, looking through a microscope, found what
appeared to be five quagga mussel veligers in a sample taken near the dam.
The DWR requested that the samples be genetically analyzed to learn whether
they were in fact quagga mussels. Through DNA testing, both the BOR lab
and Pisces Molecular, a private third party, confirmed that the veligers
were quagga mussels.
*Where did they come from?*
Nielson says it’s impossible to know where the veligers came from. “The
lower end of Lake Powell,” he says, “as well as other reservoirs on the
lower Colorado River, have a rapidly growing population of quagga mussels.
It’s possible that someone who was boating on a lake with quagga mussels
accidentally brought the veligers to Deer Creek. We’ll never know for
sure.”
*Why the concern?*
If a quagga mussel population establishes itself in Deer Creek Reservoir,
residents in Salt Lake County and Utah County, as well as anglers and those
who enjoy recreating at the reservoir, have plenty of reasons to be
concerned. For example, quagga mussels can:
clog pipes that deliver water. The cost to remove the mussels
could cost water users in Salt Lake County and Utah County millions of
dollars.
filter tiny organisms, such as zooplankton, out of the water.
Fish rely on these organisms for food. A quagga mussel infestation could
affect fish populations in the reservoir, which in turn would affect
fishing.
form massive colonies on popular shoreline areas. The mussels
smell bad and can cut your feet when you walk on them.
clog your boat’s cooling system. This can cause your boat to
overheat, leading to costly repairs.