Sounds like fun! Feds invite you to watch mayflies in the name of science


The U.S. government wants you - to help count mayflies, the pesky bugs that swarm the banks of the Upper Mississippi River each summer in southeastern Minnesota and southwestern Wisconsin.

The U.S. Fish and Wildlife Service is recruiting “citizen scientists” to observe the mayflies and gather information on them, which will help the agency better predict when they'll hatch each year, WCCO reports.

Mayflies are mostly harmless – they don’t bite or sting – and they only live for about 24 hours. But after mayflies hatch, they swarm together in gray clouds that can be a real nuisance, and even an occasional danger to drivers.

Millions of mayflies swarming together can create visibility problems on roads, and make things slippery when they fall to the ground and all die in the same spot.

Last year, for example, a mayfly-covered road caused a three-car accident in Pepin County that injured two people.

Sometimes the clouds of mayflies are so thick they can actually be seen on Doppler weather radar, as was the case in this radar image from La Crosse, Wis., last July.

In some years, cities along the river including Trenton, Wis., and Red Wing, Minn., have had to use snowplows to clear roads of inches-deep mayflies.

State and local officials want to be able to better predict when the annual mayfly hatch will occur, so that's the reason for the study, according to the La Crosse Tribune.

And that's where "citizen scientists" come in. The Fish and Wildlife Service is asking anyone who lives, travels, works or recreates near the Mississippi River to observe mayfly activity and report their findings.

"You can help monitor the health of the Upper Mississippi River, and experience a natural phenomenon seldom encountered in other parts of the world, by reporting mayfly emergence events you happen to observe," the agency said on its website.

Mayflies typically show up around the Fourth of July, plus or minus 10 days, according to Mark Steingraeber of the Fish and Wildlife Service in Onalaska, Wis. He told the Tribune the data collected by citizen observers should help him refine the model he uses to predict the big hatch every year.

For example, a more accurate prediction could help cities and counties know when to have public works officials on standby for cleanup duty. It could help determine whether the lights should be turned off on large buildings or highways to prevent mayflies from swarming near them.

And it would be especially helpful for people who are planning activities near the river. Mark Steingraeber of the Fish and Wildlife Service in Onalaska, Wis., says he often gets phone calls from couples planning their weddings who want to know what dates to avoid, the Tribune notes.

If you're interested in becoming a mayfly observer, you can find more information on the Fish and Wildlife Service website. There's also an online form and a mobile app that you can download to send in your data without having to fill out a paper form.

As for when the mayflies will hatch this year, Steingraeber said it's still a little too early to tell.

They've already hatched in other parts of the country, though. A bridge in Pennsylvania was closed for a few days last week because the flies were so thick the roadway was too slippery.

While piles of dead mayflies are pretty disgusting, the big swarms are actually a good ecological sign, as Atlas Obscura notes: Mayflies only hatch in massive numbers when the water is extremely clean, and they are a key indicator species of the health of freshwater ecosystems.

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