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Boaters despise them. Recreationists curse them. Conservationists wish to rid them from our waters. What is the object of so much hostility? The tiny, but havoc-wreaking zebra mussel. 

Why Zebra Mussels are Big Problem

Zebra mussels are native to the Caspian Sea region of Asia. They are small - the size of a fingernail - and are distinguished from other mussels by the tiny zebra-like stripes running down their shell, hence the name. This invasive species was first found in the Great Lakes in 1988 and have since then spread to nearby waterways including those in Indiana. Once established, this mussel has caused numerous problems to residents, recreationists and native species.

Zebra mussels feed by filtering microscopic plant life known as plankton from the water.  If a zebra mussel colony grew large enough, together they could filter all of the water in a lake or stream, removing plankton that  larval fish need to survive. No larval fish means no larger fish for fishing - both commercially or for recreation. Other species that feed on plankton , such as our native mussels, are also affected.

Their feeding habits are just one of the problems. Zebra mussels attach themselves to hard surfaces, anything from manmade objects to other animals. By using strings known as byssal threads or sea silk, the zebra mussels affixes itself to practically any surface and are incredibly difficult to remove.

Boats, motors, and docks have been found completed covered with zebra mussels. They can grow so densely that they can block pipelines, clogging water intakes of municipal water supplies and hydroelectric companies. Much time and money has been spent on eradicating these tiny aquatic invasives from our waters. For the Indiana Chapter, one of our greater concerns is how zebra mussels will even attach to our native mussels which proves fatal.  With many of Indiana’s native mussels on either the endangered and threatened species list, the zebra mussel could ultimately lead to their extinction.

How to Prevent Further Zebra Mussel Invasions

Once a population of zebra mussels has become established it’s impossible to eradicate them without destroying everything else that lives in the water. At this time most management efforts are geared at preventing any further spread. The Indiana Department of Nature Resources offers several simple steps can be taken to stop the further of spread zebra mussels s, such as

• Remove all plants and animals from your boat, trailer, and accessory equipment before leaving the access area.
• Drain live wells and bilge water before you leave the access site.
• Empty bait buckets on land rather than in the water.
• Wash your boat, tackle, downriggers, and trailer with hot water (above 104οF) when you get home. Flush your motor’s cooling system, live wells, bilge and other boat parts that get wet. Let all equipment dry for at least five days before transporting your boat into a new body of water. If planning to move to another body of water sooner, you should disinfect everything that came into contact with water using a 5% bleach solution.
• Learn to identify the zebra mussel so you can report new sightings. If you find a zebra mussel in a lake that is not currently identified as an invaded lake, preserve the mussel in rubbing alcohol or freeze it, and contact the fisheries biologist in your area for positive identification.