Zebra Mussels By Janelle Groff

What is a Zebra Mussel? The zebra mussel, Dreissena polymorpha, is a species of small freshwater mussel, an aquatic bivalve mollusk. This species was originally native to the lakes of southeast Russia. However, it has been accidentally introduced in many other areas, and has become a problematic invasive species in many different countries. 30, 2009

Why are they called Zebra Mussels? Zebra mussels get their name from a striped pattern which is commonly seen on their shells, though not all shells bear this pattern. They are usually about the size of a fingernail, but can grow to a maximum length of nearly two inches (5 cm). The shape of the shell is also somewhat variable. 30, 2009

Spreading A common inference made by scientists predicts that the zebra mussel will continue spreading passively, by ship and by pleasure craft, to more rivers in North America. 30, 2009

Ecology Zebra mussels and the closely related and ecologically similar quagga mussels are voracious filter-feeding organisms. They remove particles from the water column, increasing water clarity and reducing pollution. Some particles are consumed as food, and feces are deposited on the lake floor. Non-food particles are combined with mucus and other matter and deposited on lake floors as pseudofeces. 30, 2009

Effects of Zebra Mussels Zebra mussels are filter feeders. When in the water, they open their shells to admit detritus.detritus Also, as their shells are very sharp, they are known for cutting people's feet, resulting in the need to wear water shoes. water shoes

Effects of Zebra Mussels Zebra mussels are a great nuisance to people. Since colonizing the Great Lakes, they have covered the undersides of docks, boats, and anchors. They have also spread into streams and rivers nationwide.Great Lakes 30, 2009

Zebra Mussels Zebra mussels are a huge pest accidentally brought into the Great Lakes, possibly on the hulls or in the ballast water of vessels from Europe, which has been plagued by zebra mussels for centuries. March 30, 2009

Zebra Mussels can and WILL attach to anything!

Zebra Mussels… In some areas they completely cover the substrate, sometimes covering other freshwater mussels. They can grow so densely that they block pipelines, clogging water intakes of municipal water supplies and hydroelectric companies. substrate 1, 2009

Attaching to Walls…

Zebra Mussels… Zebra mussels are an exotic threat from Asia that threatens to alter water quality, habitat, and invertebrate communities throughout the U.S. Extremely prolific, zebra mussels can completely dominate benthic substrates and remove tremendous amounts of plankton from aquatic food webs. 1, 2009

Worker removing zebra mussels from Detroit Edison water intake pipes.

Affecting Boaters… There were numerous reports of boat engines overheating due to colonies of zebra mussels clogging cooling water inlets and mussels colonizing boat hulls.

Affecting swimmers… Beaches are also affected by zebra mussels. The sharp- edged mussel shells along swimming beaches can be a hazard to unprotected feet. By autumn of 1989, extensive deposits of zebra mussel shells were on many Lake Erie beaches.

Affecting Scuba Divers… One of the things that attract people to dive underwater are the many features such as shipwrecks, various fish species and underwater landscapes. Since zebra mussels attach to hard surfaces, many of the features are at risk of becoming obscured.

Short term benefits of zebra mussels don’t override long term impacts

How can you prevent the spread? Remove any visible vegetation from items that were in the water, including the boat, trailer, and all equipment. Flush engine cooling system, live wells, and bilge with tap water. If possible, use hot water. Do not re-use bait if exposed to infested waters. Dry boat and other equipment for at least 48 hours before using in uninfested waters. Examine boat exterior for mussels if it has been docked in infested waters; if mussels are found or exterior is heavily fouled by algae, either clean fouled surfaces or leave boat out of the water for at least 5 days before entering uninfested waters.

Zebra Mussels in pipe: