General: Quagga Mussels (Dreissena rostriformis bugensis) are small freshwater mussels that grow to about 1-inch long. Like their coastal cousins, these mussels attach to hard surfaces with thin, hair-like fibers. The shell is white with dark bands or stripes.

Taxonomy: Order Veneroida; Family Dreissenidae.

Quaggas are an invasive species indigenous to Ukraine. In January 2007, quagga mussels were discovered in Lake Mead, and later found in Lake Mohave, and Lake Havasu.

Similar to the more familiar Zebra Mussels, Quagga Mussels have zebra-like stripes, and quagga mussels were named after an extinct species of African zebra -- the quagga. Fortunately, zebra mussels have not yet invaded Lake Mead.

Quaggas produce dense colonies on hard underwater surfaces such as rocks, anchors, floating docks, pilings, and cement structures, plus they will colonize boat hulls, outboard motors, and boat trailers. Quaggas cause serious economic problems when they colonize and block water pipes and other structures at hydropower and water treatment plants. Currently, huge amounts of money are being spent on keeping mussels off underwater structures, and huge amounts of money and effort are being spent preventing the spread of these invasive animals.

The presence of this species in our local waters likely will end up costing water users in the Las Vegas Valley millions and millions of dollars in control and maintenance costs to keep our water lines open.

Quaggas are filter feeders that remove phytoplankton and suspended particulate matter from the water. While this increases the clarity of the water, a benefit to scuba divers, they remove the things that zooplankton eat. When the zooplankton starve to death, things like little fish that eat zooplankton starve too, and therefore the mussels are capable of altering entire food webs.

Help Prevent the Spread of Quagga Mussels

The only way to prevent the spread of invasive mussels is careful cleaning and inspection of boats, boat trailers, fishing gear, and anything else that gets in the water.

When removing a boat from infested waters, examine it for adult mussels before leaving the ramp area, then rinse the boat and trailer (including the bottom and any crevices) thoroughly with fresh water to dislodge any mussels that may have settled on the boat. High pressure jet sprayers at a car wash are good too. After washing, let the boat and trailer dry for a full week to ensure that all remaining mussels and mussel larvae are dead.

Be sure to drain bilges, live wells, and the engine cooling system immediately after exiting a body of water. Treating live wells with small amounts of chlorine bleach for 30 minutes also works well.

For more information, visit the websites of the:

100th Meridian Initiative

Protect Your Waters

Lake Mead Quagga Mussel webpage