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Mayflies emerge from Mississippi River in Dubuque

DUBUQUE, Iowa (KWWL) — Mayflies, fish flies, however you call them, have begun to emerge from the bottom of the Mississippi River in Dubuque.

The bug has been spotted in the tri-state, providing a tasty snack for fish and other wildlife that call the river home.

Normally around this time of the year mayflies can come in swarms so big they cover cars, lamp posts and can even shut down roads and bridges.

While many find mayflies gross or annoying, mayfly enthusiast Jared McGovern, Curator of Conservation Programs for the National Mississippi River Museum, says the winged insect actually tells us a lot about the health of the Mississippi River.

“In the Mississippi River here mayflies are an indicator species. There are many different species that can be classified as indicator species and what that means is they tell us something about the habitat based on their presence or their absence or their abundance.”

There have not been large swarms of mayflies in the area yet. McGovern says this may have something to do with the prolonged flooding we experienced. He says the cold spring may also be a factor.

Mayflies have a very short life span, and piles of dead ones can actually cause problems on the roads. The mayfly carcasses can cause roads to be slippery. Because of this, cities and DOT agencies rely on citizen reports of the bugs emerging.

McGovern says citizen mayfly watchers play an important role.  “Mayfly watch is going to allow you to forecast when these emergences are going to happen, and what that’s going to do is alert DOT agencies, city municipalities when to turn off their lights so the mayflies aren’t going to be attracted to the city. It’ll decrease clean up costs, it’ll make the bridges safer.”

To qualify to be a mayfly watcher all you have to do is have access to the Mississippi River. You can visit the website here to sign up.

Cori Hanna

Today in Iowa reporter

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