Column: It’s revival time for mayflies on the mighty Mississippi

Published 12:00 am Friday, August 30, 2002

Here are a few good news, bad news items based on the mayflies and the Mississippi River.

Years ago the good news was based on the arrival of summer. The bad news came with the overwhelming yearly assault of the miserable little mayflies.

Then for several decades the bad news was the obvious pollution of the river. The good news result was the gradual decline of the annual mayfly mess.

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Now the good news, according to a recent article in the New York Times, is the restoration of the annual mayfly invasions of the river towns. The alleged bad news, in reality even better news, has to be the gradual cleansing of the river water.

Right about here let’s try to explain this mayfly phenomenon. These insects are rather unusual flies with four instead of two wings. They hatch from eggs laid in streams, ponds and backwater pools. For two or three years mayflies (also known as shad flies, fish flies, june bugs and dayflies) live as larvae in the water and feed on plant life, Then the flies emerge from the water as one-inch insects.

The mayflies don’t have stingers to sting, or mouths to bite. They’re just harmless little nuisances. The mayflies have as their only purpose out of the river is to mate so the females can lay more eggs in the water to renew this particular cycle of life. All the mayflies die within a day. That certainly explains the dayfly name. Meanwhile, the swarms of millions upon millions of mayflies in each hatching cycle create real problems for the people in the river towns for a few days.

I remember seeing these flying insects one June evening years ago in one river town as they swarmed around street lights and lighted store fronts. Dead mayflies were lying on the sidewalks and streets like drifted snow. In fact, snow plows, street sweepers, and even sprinkler trucks have to be used to clean the streets and especially bridge decks.

Someone once told me a baseball game in Winona had to be canceled after several innings because so many mayflies swarmed around the ball field lights.

Here’s what one resident of McGregor, Iowa, told the New York Times writer about mayflies. She said, &uot;They’re greasy. They stick to you. They stink. They smell like dead fish.&uot; Then she added, &uot;They’re good.&uot;

That last comment is based on the proposition of the mayflies being an indication of a cleaner river and better control of unneeded pollution. One college professor says these insects are like the canary in the coal mine. Thus, if the people in river towns such as Winona, La Crosse, La Crescent, Prairie du Chien, McGregor and other communities want the restoration of a cleaner Mississippi, then they’ll have to accept the revival of the annual plague of mayflies for a few days in the summertime.

While we’re on the subject of water purity, or at least some degree of clarity, I’m reminded of a scene I observed just a year ago.

My wife and I were on an airliner somewhere between Chicago and Cincinnati as part of a trip to Alabama to attend a funeral.

The aircraft was flying at an estimated altitude of 20,000 to 25,000 feet. Down below us were farm fields, wooded areas, towns of various sizes, and roadways.

There were landmarks galore, however I had absolutely no idea as to what the names of those towns were. All I knew was that we were flying over south Indiana that afternoon.

Below us I noticed a fair sized river. The water in this stream appeared to be blue and what can be assumed to be fairly clear. A few minutes later I noticed another nearby river. This other stream appeared to be mighty muddy.

Then right below us within a short time the two streams merged. It was obvious there was a different in clarity. Sadly, the blending of those two streams resulted in what can easily be assumed to be a polluted river flowing on south to the Ohio River.

And as a closing thought, before I forget it, maybe one of those river towns could have an annual Mayfly Festival.

Tribune feature writer Ed Shannon’s column appears Fridays in the Tribune.