Stop Aquatic Hitchhikers

Photo of quagga/zebra mussels
Quagga/zebra mussels

Quagga/zebra mussels ruin boats and destroy waters. Don't let them ride with you - you can stop them.


What are they? Zebra and Quagga Mussels are freshwater, bivalve mollusks that typically have a dark and white (zebra-like) pattern on their shells. They are alien to North America but have invaded many of our waters.

Both species, Zebra Mussels and Quagga Mussels, in general, are usually about an inch or less long, but may be larger. When healthy, they attach to hard substrates much like marine mussels but unlike any native freshwater bivalve. They are often found in clusters.

Zebra mussels do not pose a known threat to human health. Biologists are concerned that zebra mussels may cause ecological shifts in the lakes they invade, with consequences to valued wildlife resources. Because these invasive mussels attach to hard surfaces like concrete and pipes, they will affect canals, aqueducts, water intakes and dams, resulting in increased maintenance costs for those facilities.

Many of these aquatic hitchhikers can harm your boat as well. These invaders will attach themselves to boats and can cause damage to boat motors if they block the flow of cooling water through the engine.

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Last updated: March 31, 2012

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