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My name is Mark Anderson. I'm an aquatic ecologist with the National Park Service
here at Glen Canyon National Recreation Area.
I've been at Glen Canyon for the last ten years. I've been in four
different positions here at Glen Canyon, all within aquatic resources.
I have a masters of science in environmental science from the
University of North Texas and Denton Texas.
Glen Canyon was aware of the mussel threat before most other entities in the
western United States.
Primarily through the efforts of a group of scientists in Salt Lake City in 1998.
They had predicted at that time, that mussels would make it into the western
United States, and that when they did they were probably going to show up in Lake Powell first.
This was quite an alarming thing for the Park Service to hear, for
people of the state of Utah to hear,
and hearing that, Glen Canyon began with the very next year, 1999,
trying to characterize - what is the risk from the mussel infestation that exists
in the eastern United States to Lake Powell? How many boats do we have coming from there?
We did that simply by counting license plates in parking lots
to start off with, and we found that in a busy weekend
you might find 70 empty boat trailers in Wahweap Marina that are
from states that have this mussel infestation. And so we judged the threat to be pretty significant.
With the very next year, realizing that, we began our prevention program.
Where we began asking people when they came through our entrance gates
if they had a boat, or a kayak, or water toys, anything that's going to come in contact with the water,
where those things have been used most recently - really in the past thirty days.
If it was from one of these states that had a mussel infestation then we would
ask them to voluntarily allow us to inspect it and potentially decontaminate it.
In 2002 we found our first boat that had been trailered to Lake Powell with mussels attached.
That was very alarming, it made this issue real for some people for the first time.
Based on that, the voluntary aspect of, "Can we look at your boat?" went away.
Where if we identify your boat as high risk you're
required to show it to us or you can't launch it on Lake Powell, as simple as that.
Then in 2007, the unfortunate news that quagga mussels had
been discovered in Lake Mead came out in January.
Glen Canyon knew that was going to really up the risk level.
Whatever risk level we were at before, now we are off the scale, because we
share a whole lot of boaters with Lake Mead.
And of course the way these things are transported around primarily is by
riding with people's boats from one place to the next.
And so based on that we had to really get busy developing an
expanded program to deal with this new level of risk.
What makes the zebra mussels different, worse in many ways
than any other aquatic invasive species that we have in the United States
is their ability to attach to hard surfaces.
They use these bissel threads. This allows them to attach to a
rock, or to a boat, or to whatever. Even then to attach on top of themselves.
They reproduce in huge numbers. Each female can produce a
million offspring each year and these offspring then come and
attach onto layers that were previously there and these layers can
build up to 18 inches thick.
Some of the impacts that would be experienced by recreational users of
Lake Powell if we got these mussels...
Including the things that have to do with their boat.
Using more gas, and not going as fast, and potentially overheating somewhere out
on the lake. But not only that, when they attach to rock walls
in a reservoir like Lake Powell with the level going up and down so much, they would be
left and stranded up on the walls where then they would begin to decompose and stink.
Potentially if they were numerous enough, the whole basin could be filled
with the stench of rotting shellfish.
They also, their shells wash up on beaches and can cut people's feet.
I've seen pictures of feet cut horribly from somebody stepping out of a boat
onto a rock where these mussels are attached. The edges of their shells of are real sharp.
It would be a terrible impact likely to the fishery. These mussels,
each one is capable of filtering a liter of water each day.
That doesn't sound like necessarily a whole lot, only one liter of water.
But they can get such huge numbers down there that it's
a lot altogether. When they do that they're pulling out all the
plankton, all the things that we were seeing in that sample that we
pulled from Lake Powell. And that's the stuff that's supporting the food chain.
So the phytoplankton are being eaten by the zooplankton, the
zooplankton are being eaten by the little fish, and the little fish are being eaten by the big fish.
And then people like to catch those big fish.
If we get zebra mussels here that whole process stops and we don't
have as many of the big fish unfortunately.
The costs of these mussels are extreme. Not only locally
to the affected water body. I believe the Bureau of Reclamation
reported an increase in their operating costs at Hoover Dam, just
in the very first year of these things being discovered, at 1.8 million dollars.
Of course, when they have additional costs to maintain their facility
and be able to keep operating, that cost is passed on down ultimately to the
consumer... where all water and power users will pay for these infestations in the west.
The most important message for people to get from this entire thing is
to clean, drain, and dry, your boat.
There are hundreds, thousands
of potential invasive aquatic species out there. Zebra and quagga mussels are just examples.
They have particularly terrible impacts. So they can get people's attention.
But this is a much, much larger issue.
Ever since people have been moving equipment around from one water body to another
this has been a problem.
Things that get associated with that equipment from one water body get taken
to another one and then they're able to establish.
Aquatic invasive species generally can't spread on their own
other than just downstream.
They can't walk from one water body to the next, they can't fly there.
So the way that they move around is by riding with people.
And so if everybody just knew - when you pull out of a water body you need to
look your trailer over real carefully, your boat trailer, the whole thing.
Remove any obvious plants or organic matter that might be there.
Let any water that's captured be released. Remove the drain plug,
empty the live wells.
Take it to a car wash, or in your backyard. Just spray it off, just get it good and clean,
and then let it dry for a few days.
There are very few aquatic invasive species that could potentially still be associated with that boat.
And if everybody did that, this would not be an issue.