*/Monthly Newsletter of the Glen Canyon Institute/*
                October 8, 2007
Volume 6 No. 3


Dear Friends of Glen Canyon,

Summer has come to a close and the leaves are beginning to fall. Autumn
is a great time to visit the Salt Lake City Downtown Farmers' Market,
and Glen Canyon Institute is going to be there. If you are in the area,
stop by for our last tabling date on October 20th to say hi.

As you know, Glen Canyon faces many threats. Recently, there has been
significant concern over the spread of the invasive Quagga mussel in the
Colorado River System. Dave Wegner, GCI's Science Director, reports on
this new ecological menace.

/Quagga Mussels Invade the Colorado River/

If it sounds like a horror story, it is. Unlike a B-Grade movie,
however, this invasion is real. Major changes will occur throughout the
Colorado River system as a result of the Quagga mussel, initially
discovered in Lake Mead in January of 2007. In June they were found in
Lake Powell, and in August adult mussels turned up in the Central
Arizona Canal in north Scottsdale. While we normally don't think of a
tiny mussel as a harbinger of things to come, this particular species
promises to change aquatic habitats in the entire Colorado River system.

Here are a few important facts about the Quagga:

     * Quagga mussels are an inedible shellfish native to the Dneiper
       River drainage in Ukraine. In the U.S., they were first found in
       the Great Lakes in 1989.

     * Quagga populations grow exponentially. A single mussel can produce
       30,000 to 40,000 fertilized eggs in one breeding cycle, equating
       to almost one million eggs released per Quagga per year.
     * Quagga prefer standing water (reservoirs and lakes), but can
       survive in the moving water of rivers and canals for many days.
       This means that they can be transported easily from one location
       to another.

     * Quagga can survive in deep reservoirs and lakes.

     * Quagga have been found in Lake Mead, Lake Powell, Lake Havasu, and
       Lake Mohave along with canals serving Phoenix, Tucson, Pinal
       County in Arizona, and as far west as San Diego and Los Angeles
       water service areas.

So why do we care? The invasion of the Quagga mussel portends a dynamic
and rapid shift in the aquatic ecosystem of the Colorado River. Quagga
mussels rapidly filter phytoplankton and other nutrients from water,
disrupting the natural food and biochemical cycles. This means a marked
depletion in the dissolved oxygen necessary to support the bio-chemical
cycles that provide nutrients and food for listed native fish and other
riparian/river-dependent species in the rivers and canyons.

In the Great Lakes, the Quagga's cousin, the Zebra mussel, has severely
disrupted recreational fisheries, native fisheries, recreational use of
the Great Lakes, and the pumping of water for municipal and industrial
uses around the Great Lakes. Now that the mussels are here in the
Colorado River Basin, there are no known controls or means to eradicate
them. Aside for costly and aggressive chlorination at water intakes,
estimated to cost Utah up to 17 million dollars annually, there is no
stopping this non-native species from impacting the Colorado River system.

Glen Canyon Institute will continue to follow this issue and report in
the future on the actions being taken by the government and states to
manage the negative impacts that will occur.

As always, thank you for your support for the work of Glen Canyon
Institute. Remember to stop by our table at the Farmers' Market! We hope
to see you there.