Monday, June 20, 2011

A Nice Surprise at Hudson Mills

Gomphus fraternus.

On Saturday, Adrienne and I did some collecting at Hudson Mills Metropark, which lies N of Dexter, along the Huron River. There are some nice stretches of cobbles and gravelly substrates there, and it's a great place for lots of riverine Odes. It has been a few years since I collected there in June, and there werev lots of teneral Argia in the vegetation, as well as a few mature specimens of Argia apicalis. I collected a female Hetaerina americana from the small stream that feeds into the Huron River -- a perfect place for Calopteryx maculata, which is abundant there, with plenty of overhanging grasses for perches. In the river, there were lots of Enallagma exsulans flying in tandem and perched on pickerelweed.

I caught what I think is a female Gomphus exilis feeding on a teneral Argia. The damselfly was nearly as long as the gomphid. A while later, while standing in a wet meadow, I looked up and saw a large ode hurtling towards me and I quickly brought my net up and captured a Macromia illinoiensis. I thought that was the nice find of the day until I caught a male Gomphus fraternus that was perched on the top of a small maple overlooing the Huron. I was standing above him on the boardwalk that crosses under North Territorial Road. It was not until I looked at the MOS database that I realized that we had no records of the Midland Clubtail from the Huron River in Washtenaw Co. Previously, I had caught the species along the Raisin River at Sharon Mill.

Macromia illinoiensis

I know I preach a lot about going to a place repeatedly, and this goes to show that it pays off.

Tuesday, June 14, 2011

Libellulids Abound

Last evening, Adrienne and I checked out Pittsfield Preserve at the S edge of Ann Arbor from about 7- 8:30 pm. The fields adjacent to Marton Road are of course, being farmed, but there is a lot of field area near the woods that has been left to grow in, and that is where the trails follow. There are some small wooded and shrubby ponds to the N, and a small wet area at the N end of the field which presumably stays filled with water long enough to allow development of some species -- I found an exuvium of Anax junius there last year.
Last night was just a beautiful late afternoon, and we observed:
Celithemis elisa
Plathemis lydia
Libellula cyanea
Libellula luctuosa
Libellula pulchella
Leucorrhinia intacta
Anax junius

As the sun got lower in the sky, dozens of dragonflies were flying around in the grass and landing, presumably for the evening. Most of those were widow skimmers and 12-spots. Only one L. cyanea was seen, and I missed it with my swing of the net. Eventually, I will have a more complete list of the odes from the preserve.