Air Date: Week of May 26, 1995

Normally a nuisance to native species in eastern US waters, the exotic Zebra mussel is now being employed by home aquarium owners as living filters. But what at first seemed like a good, low cost alternative to mechanized filters, has now proven to have its drawbacks. Kevin Niedermeier reports from Cleveland.

Transcript

CURWOOD: Around the Great Lakes region, there's concern over a new use for the pesky zebra mussel. Folks are taking the tiny bivalves out of infested bodies of water and putting them to work in their homes. Kevin Niedermier of member station WKSU explains.

NIEDERMIER: Zebra mussels were introduced into the Great Lakes through ocean-going freighters coming from Europe. And since the late 1980s, the rapidly reproducing creatures have infested bodies of water throughout the Great Lakes region. One common way zebra mussels are spread is through the cooling systems of motor boats. Someone takes their boat out of infested waters and launches it into an uninfested lake or river, spreading the larvae left in the motor. The spread of the rapidly-reproducing creatures is a concern because they clog water intake pipes and smother fish spawning grounds. But each zebra mussel can also filter 2 quarts of water a day, and people have discovered that this ability makes them an ideal substitute for electric filters in home fish aquariums. The manager of this Cleveland-area pet shop says the practice is catching on.

MANAGER: You know, they are a particle feeder, so they feed off of small particulate matter in the water. So it helps clear up the water, keeps your water crystal clear. So it's just like any other clam or mussel would do.

NIEDERMIER: Is there any concern, yourself or among the people who use these in their aquariums, that this could help spread the zebra mussels to inland waterways and so forth?

MANAGER: Really, in a closed system it's not a big problem.

NIEDERMIER: But some wildlife officials fear that it could become a problem. Dave Kelch is a Lake Erie specialist with the Ohio Sea Grant Office near Cleveland.

KELCH: What are you going to do with the water that comes out of your aquarium when you want to change the water? Are you going to dump it down your sink? Or dump it out into the yard, or dump it into the stream, or what? You could have zebra mussel larvae there. When the zebra mussels get to the point where maybe you don't want them any more in the aquarium, or you have a large quantity that die off, what do you do? Throw them in the trash can where they're going to stink? A lot of people might take them and throw them into the creek or into the ditch alongside their house or out by the road. And now we're talking about spreading zebra mussels.

NIEDERMIER: While some states have laws that prohibit taking home exotic species like zebra mussels, Ohio does not. But Kelch says even though it's legal to take zebra mussels home in Ohio, he doesn't believe that makes it right.

KELCH: So an individual wanting to collect zebra mussels from Lake Erie to put in their home aquarium isn't breaking a law. Not a strict state law; they may be breaking an ethical or a moral law, because you always help encourage the spread of zebra mussels.

NIEDERMIER: According to Kelch, people need to educate themselves to the possible negative impact of moving any species of animal from one habitat to another. He says ignorance of the possible consequences, or just a lack of concern, leads to the spread of nuisance species like zebra mussels. So far, zebra mussels have made their way into nearly 100 locations in the eastern United States and Canada. For Living on Earth, I'm Kevin Niedermier in Cleveland.