Plight of the Polistes

Let us turn elsewhere, to the wasps and bees, who unquestionably come first in the laying up of a heritage for their offspring.

~Jean-Henri Fabre, entomologist, 1823-1915

We had a wasp sting two weeks ago at summer camp. The wasps had a nest inside the locking mechanism for one of our pedestrian gates, and when the gate clanged shut, an angry wasp flew out and stung the closest person. Then, last week, a wasp stung a co-worker as she tidied up the small fairy house we have in the children’ garden. Since that area is used by many visitors, especially children, I went out to check on it, and found a wasp nest inside, which I removed. We later stuffed something in the crack where the wasp probably entered, so hopefully that will take care of the situation.

paper wasp nest

Paper wasp nest under the eaves of my office building (click photos to enlarge)

We have plenty of these paper wasps (Polistes sp., maybe P. metricus?) under the eaves of our buildings (and I have in them at home) and we all manage to get along just fine most of the time. It is usually just when the nest is down low that problems may arise. So it was, with the nest I removed. I don’t like doing that, but, after the deed was done, I decided to look more closely at that nest and the ones under the eaves. First on the list of amazing things about these creatures is that the nest is paper! Wasps scrape wood from surfaces, mix it with their saliva, and slowly create the hexagonal shapes that become cells for their eggs and developing young. The nest is suspended from a pedicel under a protected area like the eaves of a building, inside a bird house, or some other sheltered location.

Paper wasp nest close up

Closer view of the nest showing different life stages being tended by worker females

The first nests of spring are started by a mated female queen wasp that overwintered in some protected spot. She constructs that first nest by herself or with some subordinate females (usually sisters) that may have overwintered as well. Her first fertilized eggs are all female and are destined to become workers. Once they emerge, they take over the duties of caring and feeding new larvae. Workers forage for caterpillars and other soft-bodied insects that they chew up and feed to the larvae. Adult paper wasps feed on rotting fruit and nectar, so wasps are important pollinators and biological controls of plant-eating insects.. The photo above shows a worker female tending some of the brood cells. Eggs, in various stages of development, can be seen in some cells. The fat, white larvae with grayish heads, can be seen in others. Cells with paper coverings contain pupae.

paper wasp egg

Close up of a paper wasp egg

I gently tore open the nest I had removed and examined its contents. Eggs are small, somewhat oval in shape, and attached on the side walls of the cells.

paper wasp pupa

An early stage wasp pupa

As I was teasing apart one of the cells, a pupa fell out (above). I am guessing this is still a female this time of year. Toward the end of summer, the queen (also called the foundress) lays a series of unfertilized eggs, which become males. Some of her fertilized eggs will receive additional care and nutrients and may become future queens that will mate and overwinter. At the start of cooler weather, the males, female workers, and original queen all die, leaving the new batch of potential queens to overwinter.

Paper wasp larva and pupa

Paper wasp larva and late stage pupa

I placed the pupae from this nest in a container and will watch to see if they emerge. What started out as an effort to rid a space of a stinging threat has turned into a greater appreciation of a common species that I have tended to overlook all these years.