I’ve been asked a lot of questions this week. Some have been tough, like “What do you think the long-term ecological implications of the BP oil ‘spill’ will be?” Or, “Are these recent summer storms related to climate change?”
But the one I’ve heard most often, and the one I just might be able to answer, isn’t nearly so weighty or profound. The question on many people’s minds this week is, “What’s up with all the earwigs?”
It does seem like these leathery little guys are everywhere right now. Folks have reported finding them on decks and driveways, in basements and garages, even on sinks and shower curtains. In fact yesterday I found one, or at least part of one (specifically, the abdomen and cerci or forceps, a.k.a. “pincers”) smack in the middle of my desk. (Situated as it was, near a dish of assorted insect wings, it didn’t seem too terribly out of place, so I left it there. But only for a day.)
While it might seem like an invasion is underway, the real reason for the apparent increase in earwigs is much less dramatic: It’s been wet.
European earwigs, Forficula auricularia, the species we have here in the TriCities and throughout northern Illinois, thrive when it’s damp. More moisture = more favorable earwig conditions = more earwigs. Conversely, as things start to dry out, the number of potential earwig hideouts, and breeding sites, shrinks too.
This info should come as good news to gardeners, many of whom do not hold earwigs in high regard. The hungry critters often munch on leaves and blossoms, particularly young shoots, and can make a mess of fruit and vegetable plants as well as ornamentals.
But, believe it or not, earwigs aren’t all bad. Besides munching on living plants, earwigs also consume decaying plant matter and play a significant role on nature’s recycling team—the scavengers, or decomposers, that break down dead stuff and return their nutrients back into the soil.
What’s more, earwigs also have a taste for aphids and mites—creatures that can cause problems in their own right. They’ll also dine on insect eggs and larvae—even maggots on occasion.
While earwigs, by their very nature, tend to make people go “Eww!” they also possess some qualities that maybe, just maybe, might make you go “Aww…”
Female earwigs possess strong parental instincts—a trait that’s unusual among nonsocial insects. Momma Earwig will guard her clutch of 30 or so eggs throughout the 7-day incubation period, protecting them as best she can from predators, gardeners and marauding naturalists. She’ll also clean the eggs to keep them free, as best she can, from mold and fungi, which are constant hazards when your nursery is located under a rock.
Once the eggs have hatched, Mom E continues her vigil, regurgitating food and grooming her brood through their second instar, or development stage. Charming, no?
The next time you happen upon an earwig, try to resist the urge to squish it, at least right away, and have a little fun first. Maybe even learn something.
First of all, look at its “pincers,” bearing in mind that they really don’t pinch very hard, and certainly aren’t meant for you. If the set on your ‘wig is strongly curved, like ice tongs, you’ve found yourself a male. If they’re straighter, you’ve got a female.
But wait—there’s more! Earwigs, you may know, are members of the insect order Dermaptera, or “skin wings.” Yep, believe it or not, these lowly critters do have wings. Pick up your earwig, and find the thickened forewings, or elytra, on its back. Gently pull one up and—oo-la-la! You’ll see a delicate, membranous wing underneath.
Lastly, let’s dispel that persistent myth that earwigs crawl in people’s ears and lay eggs in their brains. Not true, not true at all. However, if you happen to lay your head near someplace warm and humid you may find that… Ah, never mind. Going down that road is just going to start people asking more questions…
Pam Otto is the manager of nature programs and interpretive services for the St. Charles Park District. She can be reached at potto@stcparks.org or 630-513-4346.