The earwig is a curious insect pest. It has thread-like antennae on what looks like an ant head, a long and flattened body that moves fast like a cockroach and short beetle-looking wings. What sets them apart are the long, pointy pincers extending from the rear end. It is a debate over how the earwig got its name, but they do not live or lay eggs in human ears.
The earwig found in Nebraska is the European earwig, Forficula auricularia. The earwig is long, flattened and a dark reddish-brown color with pale legs, wings, and antennae. They are often about 5/8″ long, which includes their distinct-looking, forceps-like, pincer appendages called cerci. Both males and females possess cerci on the end of their abdomen, which is used in mating rituals, defense against predators, and to hunt prey. Earwigs have two pairs of wings but seldom fly. Their hindwings are larger than they appear. They are membranous, folded, and tucked origami-style underneath short, leathery forewings. Immature earwigs resemble smaller versions of the adult but lack wings.
Although they are not considered social insects, they aggregate in large groups in the same harborage areas. Moist summers will favor higher populations of earwigs, and lay eggs in soil in the garden beds, under mulch, stones, boards, concrete structures, and other debris.
They are most active at night and attracted to lights, which in drier times, draws earwig populations to the exterior of the structure. Earwigs will get in through openings and gaps around doors, windows, cracks in the foundation and utility line/cable openings. They overwinter as adults and do not reproduce inside.
Earwigs are one of the few insects that provide maternal care. After the mother earwig lays a clutch of eggs (30-60 eggs), she provides the eggs with warmth, cleans them often, and moves them if they are in danger. After they hatch, earwig nymphs remain protected by the mother for several weeks.
Earwigs are omnivorous scavengers that eat both living and dead plants and animals (including smaller plant pest insects). Outdoors they are known to damage fruits, flowers, vegetables, shrubs, and trees by chewing irregular holes in leaves and roots. They can be found in dark and damp areas in the garden, in the mulch, around the foundation, and crammed into tight and dark cracks and crevices like the joint of wooden birdhouses and in the holes of solitary bee hotels.
Occasionally they will enter a structure in search of moisture. They are nocturnal, moisture-seeking, crack and crevice dwellers. Indoors, they are often found in basements, bathrooms, and laundry rooms, seeking shelter under rugs, mats, baseboards, and other materials that hold moisture. They survive by feeding and scavenging on any organic debris. Because they aggregate in damp environments, they are an associated with an odor and can in large numbers become an annoyance. They are not known to bite humans, but the pinchers of the male earwigs, can draw blood in defense, if handled.
Normally earwigs are not considered pests since they can provide some biological control, however in high numbers and depending on the habitat that they’re being found, they can become a nuisance.
The key to managing earwigs outdoors is to eliminate the damp, cool, dark places around the foundation. This would include cleaning the gutters, fixing the grade, adjusting the downspouts, removing leaf litter and organic matter, reducing vegetation adjacent to the structure, and avoiding unnecessary mulch or boards in gardens. It may be a good idea to consider altering the watering/sprinkler schedule, to decrease the number of earwigs around the home.
To prevent earwigs from getting inside, use caulk, sealant, or weather stripping to eliminate pest entry into the building. Reduce or change the lighting to be less attractive to earwigs, close garage, entry doors, and windows. On occasion, humans will accidentally bring a hitchhiking earwig inside on various materials, so shake out line-dried laundry and inspect objects or flowers before bringing them inside.
Trapping can be effective to reduce the number of earwigs in the garden. Homeowners can make simple pit fall traps using a shallow tuna fish can and a little oil as bait to catch foraging earwigs. Another trap can be made by leaving a rolled-up newspaper in the garden. Dropping captured earwigs in a solution of soapy water will kill them.
To remove earwigs from inside the home, scoop them up (they will not hurt you) or use a vacuum. Consider remedies to decrease the moisture and increase the ventilation in the area where earwigs are found. This can be done using fans, air conditioners, dehumidifiers, fixing plumbing leaks, hanging up wet bathmats and squeegeeing standing water in tubs/showers to drains.
Insecticide treatments are not recommended indoors, but options exist for outdoor treatments in the form of sprays, granules, dusts, and baits. There are a variety of products sold in hardware stores that have earwigs listed on the label. Some common active ingredients include synthetic pyrethroids like Zeta-cypermethrin, bifenthrin, and permethrin. Always read the instructions and follow the label.