While searching for snakes in southern Illinois this month, I flipped a rock and under it was this large (over an inch long) insect. This the only true hornet found in North America, having been introduced by European settlers in the 1800′s.
Most examples I’ve seen have been in the Autumn and are probably females (mated queens) looking for a place to overwinter before starting a new colony the following Spring. Only overwintering queens survive in protected sites such as under loose bark, in tree cavities, under rocks and in buildings. All other colony members produced in the current year perish.
I have seen European Hornets in my home state of Ohio as well. They are mainly carnivorous and hunt insects such as beetles, caterpillars, moths, dragonflies and crickets. They also feed on fallen fruit and other sources of sugary food. I saw this one at a hummingbird feeder. These insects have been observed stealing prey from spiders, which can be classified as an example of kleptoparasitism.
Though they probably have a painful sting, they usually aren’t particularly defensive when not protecting their nest. This woodland species constructs its large paper hive in natural cavities, especially in hollow trees. The nests typically have 200-400 workers.
It’s always a neat experience to observe one of these impressive invertebrates while out on a hike.