(This 802nd Buffalo Sunday News column was first published on August 13, 2006.)
A reader asks, "Why does it seem that there are so many more yellowjackets as the summer progresses?"
That's an easy question to answer. It seems there are more simply because there are more. Last winter all yellowjackets died with the exception of a few queens. Through those cold months those foundress queens carried forward the future of their tribe. They were inseminated last fall but their embryo development was delayed while they lived quietly in hollow logs, in leaf litter or in soil cavities. I once found one under a rock in our backyard. They also occasionally make their way into our homes where you may find one buzzing forlornly at a window.
In late April or early May the queens emerged, found a new nest site and built a small paper nest, an inch or two in diameter, in which she laid a few eggs. These eggs hatched and the queen fed the 30 to 50 resulting larvae until they pupated and emerged in mid-June as infertile females. These are appropriately called workers for they continued nest construction, foraged for food, cared for the queen and new larvae and defended the hive. The queen no longer leaves the hive and remains there now as a kind of lethargic egg producing machine.
And so the colony grew and finally those gray, volleyball-sized paper nests adorn our trees. By the end of this month a single nest will reach 4000 to 5000 workers and it will contain up to three times as many cells. It is at this time that males and a few queens are produced. The males serve their single role, fertilizing these queens. Then as the weather worsens the old foundress and her entire colony die, leaving only those new queens.
These nests that are so active in summer and fall are then abandoned. At that time you can impress your less knowledgeable friends by taking one down for examination, something not recommended a few months earlier. Those nests will not be reused.
Yellowjackets are, except for the bald-faced hornet, black-and-yellow. They are only slightly larger than honeybees and their antennae are all black. Unlike honey bees and bumblebees, at rest yellowjackets hold their wings parallel to their bodies. The related bald-faced hornet is black-and-white.
Although yellowjackets are only minor pollinators, they are generally considered useful insects. The adults primarily feed on flower nectar but they serve their larvae food richer in protein and that generally means other insects, often harmful ones.
The problems we have with yellowjackets arise at this time of year when their usual food sources are less readily available. Now they often turn to carbonated beverages, juices, jellies and jams, candy, ham, bologna, fish, cake and ice cream -- exactly the foods that we love to take on picnics. And indeed, they can completely disrupt a picnic or become a nuisance around restaurants or your home.
Of course they also sting: not just once like a honeybee, but many times. Unlike bee stings, the yellowjacket's is an offensive weapon, one it uses against the insects it kills to feed its larvae. Thus the venom is different and most people consider it harsher than a bee sting. Entomologist Justin Schmidt describes the hornet's sting as "similar to getting your hand mashed in a revolving door," and he says of the yellowjacket: "Imagine W. C. Fields extinguishing a cigar on your tongue." These stings are indeed painful but to some people with allergies they represent a more serious threat. About 500 people each year die of the associated anaphylactic shock. Such people should seek guidance from their physician.
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