Classification (Anisozygoptera). I have been enjoying the dragonflies, also. The nymphs are dark green or brown, and are usually found covered in algae. They feed on aquatic invertebrates such as mayfly larvae and small crayfish (small crayfish!!!), and also on small aquatic vertebrates such as tadpoles and minnows. They fly up to 34 mph. I found one half out of it's newly moulted nymph stage. It didn't make it and died, halfway into a new life. It looked like a transformer. One time I saved a dragonfly that was caught in a spiderweb, he made such a racket I went to investigate. The spider didn't want anything to do with him anyway, ha ha.

Yeah, it's horrible over by Cub and Home Depot. Hordes of dragonflies are emerging, only to fly across Central Entrance at low altitude...

Once a year, it's is the season for dragonflies.

They showed up in my back yard last Saturday - I love seeing them hanging around the yard, and yesterday as I had lunch on my deck, one seemed to enjoy sitting on the top corner of my MacBook for about 20 min.

Yeah, most of them are juvenile four-spotted skimmers. I've noticed a few of other species, too. But the vast majority are the new molts. They *do* eat mosquitoes and flies and other flying insects when they are adults. It's when they are nymphs that they eat stuff in the water. Four-spotted skimmers also will catch and eat other dragonflies. 

If you go to a pond, you can watch them fight each other as they try to establish territories. It's like a middle-school playground out there. At Hartley and another pond nearby, I've seen lots of chalk-fronted corporals, whitetails, and 12-spotted skimmers too.

+1 on Dragonflies of the North Woods. That whole "of the North Woods" series is great. They just came out with a new one on insects, by U of M Extension entomologist Jeffrey Hahn. Book + magnifying glass = hours of nerdy fun.