This afternoon, Blackburnian suggested we take Raven across the lake to the park and do some exploratory hiking. I thought this was a great idea, so we bundled Raven into her harness, hiked down to the boat (now no longer docked at the dock because the water level has gone down so much from dam control that the dock is surrounded by mud), and boated across to the park.
We had a great hike. Surprisingly, this is the first time I’ve gone over and hiked around myself, though Blackburnian’s been there a few times. For whatever reason, I’d just never made it, other things had come up. So it was nice to see a bit of the park interior. I’ll elaborate more on the hike tomorrow.
One of the things we came across while hiking, though, was this underground paper wasp nest. Aside from the fact that it was a wasp nest built of paper underground, we really had no idea what it was. So I snapped a few photos, with the intention of looking it up when we got home. The wasps were totally unconcerned with us being there, and me nosing up to the mouth of the burrow it was set in so that I could take photos. They just went about their business, popping inside the entryways in the paper, one or two flying away while I squatted there.
I was surprised to find, when I got home, that this was the nest of Eastern Yellowjackets (Vespula maculifrons). I don’t know that I’ve ever consciously looked at a yellowjacket and thought, “that’s a yellowjacket,” so I’m not sure what I was expecting. Something more yellow, maybe. I knew yellowjackets primarily nest underground, but for some reason this didn’t twig with me. Plus, yellowjackets have a ferocious reputation, and here these were, apparently unconcerned. Nevertheless, the wasps in this burrow were Vespula.
Yellowjackets as a group build paper nests using wood and plant fibers mixed with saliva. They can make some beautiful patterns in the paper they create, scalloped sea-shells of grays and whites. They’re a social species, like many of the Hymenoptera, with a single reproductive queen cared for by many female worker offspring. Although the larvae are fed bits of chewed-up insects, the adults themselves feed on nectar from flowers. They’re also not opposed to visiting sugary drinks, and are probably the wasps most commonly seen crawling into pop cans.
The colonies never survive the winter, despite being nestled underground. In the fall, male drones and young queens are produced from the colony, and these then fly away to mate. In the photo above you can see three workers, the slightly smaller ones with more yellow, and one male, the slightly larger one with more black, on the left. The new queens will mate with the males; the males will then die, while the queens find a safe place to hole up for the winter. They are the only ones to survive. Come spring, they find themselves an abandoned burrow, and start up a new colony. They begin from scratch, and the first brood is completely cared for by only the queen. Once she’s raised a few workers, she settles in to her role as egg-layer, and her daughters run the nest. By the end of the summer the nest may hold up to 5,000 individuals.
Interestingly, all workers are females because they are diploid – having two sets of chromosomes. Males are created through the laying of unfertilized eggs (the queen, who holds the sperm from her mating the previous fall in a storage chamber in her abdomen and doles it out according to the gender of offspring needed), and are therefore haploid – have just one set of chromosomes. New queens are diploid females that are fed a special concoction (in honeybees, called “royal jelly”) that promotes her development into a reproductive individual.
I gather the workers will sting if provoked, and their sting can be acutely painful. However, probably just walking by won’t provoke them. On the other hand, the juicy, tender larvae are a favourite delicacy of bears, skunks and others, who will endure the workers’ stings for the treat. As long as you’re not digging in to the nest for a snack you’re probably fine.