Midges in Rocky River Monday, June 4, 2018. (Laura Johnston, RocktheLake)

If you live near Lake Erie, you woke up to midges — tiny flying insects clinging to your window screens or car doors.

The mosquito lookalikes will hang around for the next 10 days or so, long enough to mate, reproduce and die. You won’t see them again until October.

“They want to swarm. That’s how they find their mate,” said Matt Thomas, the laboratory manager at Ohio State University’s Stone Lab near Put-in-Bay. “So they have to do these large mating swarms. They don’t bite. They’re not vectors of disease. They’re just kind of an annoyance for people who live along the lake.”

So why do midges arrive for NBA and Major League Baseball playoffs? And how are they different from mayflies? We’re glad you asked.

When do midges hatch?

About the beginning of June every year, when the lake temperature rises and the days get longer. Thomas says there is no one optimal water temperature.

That just happens to coincide with Cavs playoffs, said Marty Calabrese, a Cleveland Metroparks naturalist. The eggs this generation of midges lays will hatch in the fall, just in time to reek havoc at any Indians playoffs games. 

The exact timing is hard to predict, Thomas said.

Do midges indicate water quality?

Yes, but it’s complicated. Midges can tolerate pollution. So unlike a big mayfly hatch, a big year for midges does not say much about the healthiness of Lake Erie, Thomas said.

The Northeast Ohio Regional Sewer District does not study midges, but a senior investigator there calls them “organisms of interest because they have varying tolerance of pollution.”

Do they bite?

Nope. Nor sting.

So how are they like mayflies?

Mayflies are bigger. They also come ashore to mate before returning to the lake to reproduce. And their existence is proof that Lake Erie is healthier than it once was. We’ll see them in a few weeks.

How far do the midges go?

They can be blown a mile or two from the lake. Calabrese saw them in Cleveland Heights today. 

What happens after they hatch?

The males swarm, often around sunrise or sunset, and the females fly in to find a mate. They no longer eat. After they mate, the female returns to the surface of the water and lays eggs, which gradually sink to the bottom. Then they die.

When that group is ready to hatch, the larvae swim to the surface, then molt. Their wings come out and they fly off the surface of the water.

Why do midges matter?

Adult midges are eaten by fish, bigger insects, bats and birds.

Where can you see them?

Pretty much anywhere near the lake. Sunset is a great time to see swarms. Just don’t get caught in one.