Pulling Zebra Mussels
DB: This is Earth and Sky. As recently as the late 1990s, if you pulled a fishing boat from a Michigan lake, you might have seen a few Zebra mussels attached to the boat.
JB: Now when boats are removed from the water, they’re covered with the small dark mussels. Zebra mussels aren’t native to North America. They probably arrived as stowaways in the ballast water of ships from Europe. The first Zebra mussels were found in the Great Lakes in the mid-1980s. They’ve now moved into hundreds of other lakes – as well as the Mississippi River and its tributaries.
DB: Zebra mussels latch onto docks, boats and rocks. Lake bottoms and beaches get covered with their shells. They clog water intake lines and drinking-water pumps. They are excellent water filterers. The water they filter looks clearer, but the pollution stays in the mussels’ tissues – to be released again when they die. And Zebra mussels filter out microscopic life at base of the food chain – creating less food for other aquatic creatures.
JB: Power and water plants have tried chemical treatments, but they cause environmental problems. Some species of ducks eat mussels – but there aren’t enough ducks to control them. As yet, researchers haven’t come up with a good way to get rid of Zebra mussels once they’re established.
DB: Today’s program was made possible by the National Fish and Wildlife Foundation, in cooperation with the U.S. Forest Service. We’re Block and Byrd for Earth and Sky.
The following individuals were interviewed for today’s show. Our thanks to:
Sandra Nierzwicki-Bauer
Professor of biology
Rensselaer Polytechnic Institute
Jeffrey L. Ram
Dept. of Physiology
Wayne State University
Detroit, MI
The following books, articles and web sites were used in preparing this script:
Natalie Ram, From Russia with Love. C.P.Allen High School, Bedford, Nova Scotia. (1996)
Invasive Species: Zebra Mussel Profile (InvasiveSpecies.gov)
Biologists Gain a Toehold Against a Pesky Mussel (Rensselaer Polytechnic Institute)
Author’s Notes:
One old-fashioned method has proved somewhat successful: manually pulling the troublesome mollusks from the water.
Scientists believe that the North American zebra mussels most likely came from the warmest portion of the zebra mussel’s European range, the northern shore of the Black Sea. More specifically, they came from the lower Dneiper or Bug Rivers, near the Ukrainian seaports of Kherson and Nikolayev.” So we know that zebra mussels are in those areas. Also zebra mussels spread from those same areas all over Europe during the 19th century, including to Poland, Germany, France, Sweden, England, etc.
And because the water is clearer, increased light causes more plants to grow. That changes fish habitat.
When birds eat zebra mussels they get elevated levels of contamina+nts which lead to reproductive problems.
Additional Teacher Resources
Invasivespecies.gov, Species Profile: Zebra Mussels, Dreissena polymorpha
A great resource! This site is filled with images, recent news, information, scientific articles and links to a variety of different sources on invasive species including Zebra mussels.
U.S. National Oceanic and Atmospheric Administration: The Origin of the Great Lakes Zebra Mussels
Since the Zebra Mussels first invaded the Great Lakes in 1988, research has centered on understanding the impacts these mussels have had on the Great Lakes’ economy and ecology. But the question of where exactly these mussels came from still lingered. This article explains their origins as well as the implications of their current status.
U.S. Geological Survey: Zebra Mussels in Southwestern Lake Michigan
This article covers the origin of the Zebra mussel in Lake Michigan and its following population explosion in and around the Great Lakes region.
U.S. Geological Survey, Upper Midwest Environmental Sciences Center: Zebra Mussels
This site provides a brief scientific overview of the Zebra mussel in the Great Lakes Region. It covers the species effect on the ecosystem, how far they have spread, and what scientists are doing to prevent the spread.
