It’s been very rainy here the last couple of days – since I finished and mailed off the moth guide, basically. As if the weather knew that I’d suddenly have lots of time for hiking about and enjoying the last of autumn. Since I haven’t been out (I’m very much a fair-weather hiker, or at least not a poor-weather hiker), here’s another photo I’ve had collecting dust on my hard drive for the last week or so.
I noticed this wasp on a short stalk of goldenrod as I was walking back from checking out the earth tongues. A wasp on a goldenrod is not in itself all that unusual. Wasps seem plentiful at this time of year, but they’re nearly all Polistes paper wasps. This wasp looked strange, and when I peered closer its pinched abdomen, with swollen, bulbous tip, was pretty obvious. I couldn’t recall having seen a wasp of this shape before (mud daubers also have very thin abdomens, but theirs are thinner for longer, and very distinct), so I took a photo and looked it up in my trusty Kaufman Guide to Insects when I came home.
As it nearly always does, the KGI had the answer. This was a potter wasp, most likely Eumenes fraternus, a widespread wasp of eastern North America. According to BugGuide.net, this species favours scrubby fields and forest edges, which is appropriate to the habitat I found it in, and can be found from mid-summer through fall at more northern latitudes like here. Adults feed on nectar, and are often found on flowers.
The name of the group, potter wasps, comes from their habit of sculpting their nests from mud. The cells of the nest are adorable little spherical creations with a flared opening that look like tiny clay jugs. These are provisioned with caterpillars or small sawflies, an egg is laid on the prey item, and then the chamber is sealed off until the new adult wasp is ready to emerge. Larval wasps will spend the winter in their pots.