What kind of bugs will hover above trees in giant, narrow columns?

July 10, 2006 9:34 AM

What kind of bugs will hover above trees in giant, narrow columns?

This article about a hatch of mayflies showing up on National Weather Service radar reminded me of this time a few years ago that my wife and I were driving down the expressway in West Michigan and noticed these huge columns of tiny bugs circling above the trees on the side of the road. Sort of like very tall, thin, slow tornadoes.

The individual bugs were too tiny to see, but there must've been thousands of them because the columns extended probably 50 feet above the trees, and were probably two feet in diameter.

It was one of the weirdest, creepiest things I've ever seen, and I've never seen it again. Has anyone ever seen anything like this? Any photos of it on the web?

I remember gnats flying over my head out in right field when I played tee-ball. But if I'd ever seen anything like this, I'd have been afraid they were going to lift me up and carry me away!

posted by elvissinatra to science & nature (9 comments total)

It probably is gnats, just a different species with different behaviour than you remember. Here is the Straight Dope's take on it.
posted by TedW at 9:42 AM on July 10, 2006

I think these are exactly mayflies.

I saw these columns myself this year in early June in Ontario, and last year I had the misfortune to drive through a cloud of them which had just hatched from the Beaver River where it passes through Kimberley, Ontario. I was exactly like driving through a torrential downpour of insects, and I had to keep the windshield wipers and wiper fluid going constantly to be able to see. It lasted for about two miles and when I finally got to my destination, the insects had formed a crust about an inch thick on the headlights and windshield rebate. Even the radio aerial was crusted with dead (big) mayflies. It was fucking terrifying. The noise was indescribable, like being in an an organic hailstorm.

My buddy Tom used to work at a gas station nearby and he said that there'd be one weekend a year where he had a stream of cars stopping in with traumatised drivers, completely covered with a mush of dead insects which he would squeegee off for them.

If you ran out of wiper fluid you'd just have to abandon the car.
posted by unSane at 9:43 AM on July 10, 2006 [2 favorites]

I doubt these were mayflies that you saw. Mayflies are very poor fliers and, barring strong winds, are not found far from the body of water from whence they hatched. These are probably midges(scroll down to the post titled "water midges") They are also called gnats. They belong to the family Choronomid (sp?) and look very similar to mosquitos, although they don't bite and are harmless. They have aquatic pupae, and these were likely clouds of mating adults. Were you close to the Lake? My family has a cottage on Lake Erie and I would often see similar clouds of midges.
posted by fantastic at 10:40 AM on July 10, 2006

Water midges! "Small clouds of males are frequently seen hovering in the air over or near water. At times, they form larger clouds that look like smoke over trees or tall structures." That's totally what I saw.

Now that I think about it, that stretch of expressway runs right along the Grand River. So there we go. Thanks!
posted by elvissinatra at 11:13 AM on July 10, 2006

The things that crusted all over my truck were definitely mayflies (they were WAY bigger than midges and made very loud splatting noises, like hail). However the columns I saw could well have been.
posted by unSane at 11:19 AM on July 10, 2006

Take this from a Scot: Midges do bite, and are not harmless. They're flying scum.
posted by bonaldi at 12:30 PM on July 10, 2006

Only some midges bite.
posted by cellphone at 4:59 PM on July 10, 2006

Speaking of Mayflies, a couple of days ago there was a mass hatching of mayflies, so many in fact that it showed up on weather radar.
posted by Steven C. Den Beste at 5:59 PM on July 10, 2006

Steven, check out the link in the question :)
posted by gentle at 5:27 PM on July 12, 2006