Why are bugs falling out of the sky?

Factual Questions
1

I’ve been playing tennis at night for about the past week and I’ve noticed a strange phenomenon. When we turn the lights on, hundreds of bugs swarm around the lights. The strange part of all this is that these huge black beetles keep falling on the court. They lay there on their backs and wiggle their legs around for a few minutes and then just get up and fly away. What is the deal here? The beetles are about one to one and a half inches long if that helps. These suckers are huge.

2

Probably big Dytiscid or Hydrophilid beetles. They’re mostly aquatic, but can fly well and will migrate from one body of water to another. On some warm evenings they occasionally seem to come out of the water en masse. They’re attracted to lights, so they’ll fly to a source, then thrash around it. About 15 years ago I was working as a ticket-taker at the Oakland Coliseum ( in CA ) during an evening baseball game, and literally hundreds of big Hydrophilids ( Tropisternus, I think ) rained down on the area, probably emerging from the creek/slough that passes by the stadium. They were all gone ( except for a very few carcasses ) the next day.

What you may be seeing is the Giant Black Water Beetle ( Hydrophilus triangularis ). Here’s a picture:

http://www.enature.com/fieldguide/showSpeciesSH.asp?curGroupID=4&shapeID=1011&curPageNum=9

  • Tamerlane
3

Good answer, but why are they falling? Are they like June Bugs and fly into things, which knocks them down?

4

Kniz: Yeah, pretty much. And that ( June Bugs ), by the way, is another excellent possibility :slight_smile: . I had forgotten entirely about those critters ( odd, since I used to “collect them” as a child in Michigan ). Right size and black. Plus they’ll be out multiple nights. Here’s a picture:

http://entweb.clemson.edu/museum/beetles/local/btle39.htm

and here’s an interesting, ah, account:

http://www.wwmag.net/Pages/junebug.htm

  • Tamerlane