The insect commonly called a “pincher bug” is actually the earwig, a member of the insect order Dermaptera. These creatures are easily recognized by the pair of forceps-like appendages, or cerci, extending from the rear of their abdomen. Despite their frequent presence in damp areas, a common question is whether these insects can swim. This article explores the earwig’s interaction with water and its aquatic survival.
Survival and Movement in Water
Earwigs are not effective swimmers because they are primarily ground-dwelling insects that lack the specialized physiological adaptations for aquatic life. They do not possess specialized appendages, such as paddle-like legs, nor do they have a system for breathing underwater. Any attempt at sustained, directional movement in water is clumsy and ineffective.
When an earwig accidentally falls into water, its movement is a short-term survival mechanism, not true swimming. The insect may actively tread water, but this effort is mainly to keep its respiratory openings, or spiracles, above the surface. Its body structure allows it to float, becoming a passive survivor on the water’s surface tension.
The earwig’s cuticle, or outer shell, provides buoyancy, helping it stay afloat. Under ideal conditions, an adult earwig can remain floating for a significant period, sometimes surviving for up to 24 hours while passively carried by the water. This survival window depends on factors like water temperature and the insect’s exhaustion level, and it does not indicate any capacity for self-propelled navigation.
Preferred Damp Environments
The fact that earwigs cannot swim might seem contradictory to finding them near standing water, but this is explained by their profound need for high environmental moisture. Earwigs are highly susceptible to desiccation, meaning they can quickly dry out and die if the surrounding air is too arid. They seek out damp, dark, and cool microclimates to prevent moisture loss.
They are nocturnal, emerging at night when the temperature is cooler and humidity is naturally higher, which facilitates foraging. This preference for moist surroundings is why they are often found near outside faucets or in areas with poor drainage. Typical outdoor habitats include areas with trapped moisture, such as:
- Under stones
- Decaying logs
- Piles of leaf litter
- Thick garden mulch
When earwigs move indoors, they are searching for a continuation of these humid conditions, often drawn by moisture problems. They frequently congregate in basements, bathrooms, and kitchens where plumbing leaks, condensation, or high humidity levels provide a suitable environment. These insects are attracted to the moisture itself, which explains their need for damp habitats rather than any capability to move through water.