ZEBRA MUSSEL

Zebra Mussel (Dreissena polymorpha) is a small mollusk native to southern Russian and Ukraine...I think you can see how it got its name. It found its way into the Great Lakes in the U.S.A. via ballast tanks on ocean going vessels. From the Great Lakes, it has found its way into rivers and lakes around the Northeast and Midwest via "live wells" on fishing boats or from boats themselves to which the mussels have attached.

The larval form of this pest is motile and is called a Veliger. These larval forms can be taken into the live wells of fishing boats and, unless disinfected, can be moved from lake to lake in this fashion. There is even evidence that suggests the veligers can be moved from lake to lake in wet feathers of aquatic birds.

Eventually the veligers settle on some substrate and grow into the mussel (clam shaped) which is a filter feeder. They can grow up to two inches in length but the vast majority are in the neighborhood of 1/4 to 1/2 inch in length.  These mussel colonies can grow to several hundred per square foot ( thousands per square meter) of area and each is capable of filtering a quart of water a day ...about a liter. They filter out algae increasing water clarity and taking away food necessary to the young of several important local fish species. They clog water intakes for drinking water utilities and for cooling of power plants costing many hundreds of thousands of dollars in cleaning costs...which are, of course, passed on to the consumer. 

In addition, they are so numerous that the shells of deceased mussels cut the feet of swimmers where they are prevalent.

From Wikipedia:

"The lifespan of a zebra mussel is four to five years.[6] A female zebra mussel begins to reproduce within 6–7 weeks of settling.[12] An adult female zebra mussel can produce 30,000 to 40,000 eggs in each reproductive cycle, and over 1 million each year.[13] Free-swimming microscopic larvae, called veligers, drift in the water for several weeks and then settle onto any hard surface they can find. Zebra mussels also can tolerate a wide range of environmental conditions, and adults can even survive out of water for about 7 days."


This invasive species is causing irreparable harm to the native ecosystem of the Great Lakes and surrounding waters.

Best in Large.