Aerial yellowjacket (Dolichovespula arenaria)
This week’s crawly is the local species of yellowjacket you’re most likely to notice – their nests at least – but the species least likely to notice or bother you.
Meet the common aerial yellowjacket (Dolichovespula arenaria).
Common aerials are one of only two aerial yellowjacket species in our area, so the pretty paper nests you see under eaves or in trees are either common aerial nests or the nests of their cousins the bald-faced yellowjacket.
All our other species of yellowjackets are ground nesting wasps, and those species are the ones who insist on crashing your bar-b-que or picnic (remember to leave an offering away from your picnic area to keep those other yellows at bay).
For brevity, we’ll call common aerials “aerials” for the balance of this article.
Speaking of names, let’s break down aerial’s binomial. Their Genus name Dolichovespula comes from the Latin for “long-little hornet” and the species name arenaria comes from the Latin for “sandy.”
No one knows for sure how they got the “sandy” moniker because aerials actually live in wooded areas. Maybe some long ago scientist saw one drinking from some sandy soil along a creek or river and the name just stuck.
Why do we call them “aerial” yellowjackets? Our local yellow jackets are in one of two genera; Vespula and Dolichovespula (say that ten times fast!)
Vespula are ground nesting yellowjackets, the ones we literally most often stumble upon or mow too close to or… you get the gist. Vespula build above-ground nests anywhere from a foot off the ground under a rocky overhang to 50+ feet up in tree branches.
The nests we generally see are those built under our house eaves. If an aerial yellowjacket nest is built away from a doorway – thus won’t be disturbed by frequent vibrations – these ladies won’t bother humans.
As yellowjackets go, aerials are far less defensive of their nests than ground-dwelling yellowjackets.
Fun fact: The smaller the colony (thus the smaller the nest), the less defensive yellowjackets are.
Funer fact: If aerials do need to defend their nest, these ladies don’t just sting but can spray venom from their stingers (modified ovipositors). That’s bad news for the optimistic raccoon who thinks they can make a midnight meal of an aerial nest.
Other potential predators of aerial nests include skunks and opossums. They’ll tear apart the nests to get to the tasty (well, to a raccoon anyway) larvae.
How do aerials construct their nests? Like their distant cousins, paper wasps, aerial yellowjackets chew wood with their mandibles, mix it with saliva, then use that to construct their nests.
First the queen constructs a few cells and lays the first worker eggs. While waiting for the eggs to hatch she’ll begin the outer layer of construction, the paper walls which will surround the cells.
The Queen Aerial will feed the first round of babies, and once they are winged adults, they’ll take over cell and wall construction duties as well as the care of the balance of the young. The queen will then have the sole duty of egg laying.
When winter comes, nearly the entire colony will die out, including that year’s queen. A few new queens will hibernate overwinter to begin the next spring’s colonies.
Fun fact: Fertilized eggs become worker yellowjackets, unfertilized eggs (laid very late in the season) become male yellowjackets and the very last fertilized eggs laid just before winter are the new queens.
While the many workers are out working, they are providing several benefits – because yes – yellowjackets are beneficial insects!
They are native pollinators and aerials need a lot of nectar, so they do a lot of pollinating. They are also free pest control as they feed their babies a variety of other arthropods such as grasshoppers, crickets, caterpillars, spiders, flies, lacewings and even termites. They also love to chow down on fall webworms.
Unlike their ground-nesting cousins, aerials aren’t really into chomping on carrion, so while they aren’t part of “nature’s clean-up crew” they also have no interest in your hamburgers, steaks or chicken wings.
So feel free to enjoy the lovely aesthetics of aerials’ intricate nests – or usefulness for craft projects once the colonies die out in winter. You can do so knowing as long as you don’t bump into a nest (though try to stay 10 or more feet back to be sure), these nifty beneficial ladies will go about their daily tasks from March through October and leave you and your bar-b-que alone.
