Zebra Mussels slowly are spreading to more Minnesota lakes. This nasty invasive species changes any water into which it is introduced. The discussion you might be hearing or reading about concerns efforts by the Minnesota Department of Natural Resources to limit if not halt this spread.
Birders really should pay attention if they're not already doing so.
Outdoor writer Doug Smith discusses this clearly and well in a column he wrote for a recent edition of the StarTribune.
So far, we have heard from fishermen and lakeshore owners. The unfortunate divide is obvious. Lakeshore owners have money in the game; Zebra Mussels in their lakes would be a real problem in both use of the lake and sale of the property. Some fishermen find the idea a nuisance.
Most, perhaps most, fishermen understand that they are the link in the chain of concern. But not all fishermen are taking the preventive measures needed to ensure no contamination. Prevention means thoroughly cleaning tackle, boats, trailers, etc. – any surface or container that could carry the mussel or its larvae.
The DNR reports its inspection of boats at random roadside stations has shown noncompliance of more than 35 percent.
Birders should share the concern of lakeshore owners. Zebra Mussels create major changes in any water they inhabit. They multiply rapidly. A lake can go from no mussels to millions and millions in a few years. The mussels eat by filtering from the water microorganisms that currently form the base of a lake’s food chain. Fish numbers and species could change if fish compete with the mussels. Water clarity changes; it can become tap-water clear. This in turn changes vegetation patterns.
These things have impact on bird species using those lakes. The changes might be subtle, but change in nature is hardly ever for the better. Any man-made change from the conditions into which the lakes have evolved is harmful. Nature really does know best.
The Zebra Mussel discussion is characterized by some as anglers versus lakeshore owners. It’s more than that. Birders have an interest in seeing that mussels do not spread. If you have a chance, get into the conversation. Once the mussels are introduced into a lake they are there forever.
(Below, Red-necked Grebes. They are among Minnesota waterbirds that eat fish. Male grebe is in the foreground, female behind.)