Earwigs (order Dermaptera) are easily recognized by the prominent, forceps-like appendages extending from the rear of their abdomen. This distinctive feature often causes widespread apprehension about their potential to inflict harm. Despite their alarming appearance, the fear surrounding them is largely based on misconception. Earwigs do not possess the ability to bite a person in the conventional sense, but they can use their rear appendages to deliver a defensive pinch.
The Direct Answer: Do Earwigs Bite?
Earwigs do not bite humans because their mouthparts, or mandibles, are not designed for piercing human skin. Their simple, biting mouthparts are used primarily for consuming plant matter and small insects. A defensive reaction from an earwig is almost exclusively a pinch, which is a reflex action when the insect feels trapped or handled. This pinch is only delivered if the earwig is severely threatened, such as when it is accidentally squashed or picked up. Earwigs are non-aggressive insects that prefer to flee and hide in dark, damp places rather than engage with a person.
Understanding the Pincer Mechanism
The claw-like structures extending from the earwig’s abdomen are technically called cerci. These cerci are not venomous stingers, but hardened, modified abdominal segments that serve multiple biological purposes. They are functionally different from the mouthparts and are used far more frequently than the earwig’s actual mandibles.
The cerci exhibit a difference in shape between the sexes. Male earwigs generally possess larger, more curved cerci, which they use during mating rituals and to spar with rival males. Female earwigs typically have straighter cerci, which are better suited for burrowing into soil to create a nest for their eggs.
The cerci are also used to help fold and unfold their complicated, fan-like wings. When not in use, these large, membranous hindwings are intricately tucked under the short, leathery forewings, a process that requires specialized manipulation. The cerci are also employed to help secure and manipulate prey, such as aphids or mites, before consumption.
Health Implications of a Pinch
An earwig pinch is rarely a cause for concern, as the force exerted by the cerci is usually not enough to break the skin. The sensation is often described as a minor snap or a momentary, superficial discomfort, similar to a strong nip from a fingernail. Earwigs do not possess any venom or poison, meaning the pinch cannot inject toxins into the skin.
There is no scientific evidence suggesting earwigs transmit diseases to people or pets. The small injury they might inflict is generally harmless, healing quickly without any need for specialized treatment. The primary risk comes from the possibility of secondary infection if the skin is broken, as earwigs live in soil and damp organic matter.
To address a pinch, the affected area should be immediately and thoroughly washed with soap and warm water. If the cerci managed to break the skin, a small amount of antiseptic cream can be applied to minimize the chance of infection. Monitoring the area for excessive redness, swelling, or persistent pain is advised, but severe reactions are extremely uncommon.
Keeping Earwigs Out of the Home
Earwigs are attracted to dark, cool, and moist environments, making indoor spaces with water issues particularly appealing to them. Addressing any excess moisture both inside and immediately outside the home is the single most effective way to prevent their entry. This includes fixing leaky plumbing, ensuring gutters and downspouts are clear, and running a dehumidifier in damp areas like basements or crawl spaces.
The second strategy involves physical exclusion by sealing potential entry points into the structure. Earwigs can squeeze through tiny cracks and gaps, so applying caulk around utility lines, windows, and door frames is an important step. Gaps under exterior doors should be fitted with weatherstripping or door sweeps to block access at ground level.
Outside the home, remove or modify the moist habitats earwigs use for shelter during the day. Clear away accumulations of leaf litter, grass clippings, and dense ground cover that are directly against the foundation. Moving firewood piles and thick layers of wet mulch away from the perimeter can eliminate their preferred hiding and breeding spots.