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Perhaps the most notorious of aquatic invasive species, quagga and zebra mussels have caused billlions of dollars of damage in the U.S., particularly in the Great Lakes region. These closely related mussels have been making their way west from the Great Lakes, attaching themselves to boats and fishing equipment and catching a ride to new waterways.  The threat of mussels is primarily an effect of their high reproduction rates.  A single female mussel can produce several thousand eggs in one season.

Potential harms:

The dense populations of mussels have several effects.  Mussels cause ecological problems by dominating food chains and littering beaches. Most notably, mussels cause vast economic damage.  With their ability to attach to hard surfaces, mussels often condense in water intake pipes used by power plants and water treatment facilities creating mass clogs and millions of dollars of damage.

Prevention:

Most mussels are spread via boats and are very difficult to eradicate.  Therefore, the best way to avoid ecological and economic problems is to prevent the spread of mussels by remembering to Inspect, Clean, and Dry boats, especially when in known infested waters.  Remember, mussels can survive several days out of the water.

Identification:

• Quagga and zebra mussels are approximately the same size.
• Adults are typically the size of a fingernail but can grow up to 2 inches long.
• The shell patterns of zebra and quagga mussels differ a bit. Zebra mussels have a striped pattern resembling a zebra. Quagga mussels have a pattern of rings darkening in color on the edge which is typically rounder than a zebra mussel.
• Zebra and quagga mussels can also be distinguished according to their locale. Quagga mussels are often found in deep waters downwards to 90 feet.  Zebra mussels are found in water 50 feet or shallower.

To check for zebra and quagga mussels on your waterfront property first examine your dock for mussels.  Also, free substrate are available from Fish, Wildlife, and Parks. You can make your own by attaching a PVC pipe to a piece of string and hanging it the water.  Check it at least once a month for the appearance of mussels.

Links to more information zebra and quagga mussels:

http://www.protectyourwaters.net/hitchhikers/mollusks_zebra_mussel.php

http://fwp.mt.gov/fishing/guide/ANS/molluscs.html#zebramussel

http://www.seagrant.umn.edu/ais/zebramussel#general

http://www.miseagrant.umich.edu/downloads/ais/fs_quagga_mussel.pdf