Even then, it's the bacteria they bring with them, rather than the earwigs themselves, that give humans trouble. Earwigs are scavengers. They eat small insects and decaying plant and animal matter. Warm summer weather makes earwigs more active. They may stay active in the fall if they find relatively warm shelter.
Earwigs live in damp areas, usually around, underneath or in vegetation.
They can also be found in and under piles of wood, lumber and other items stored around building foundations. Although other insects also fall into wells, the cool, moist environment of a well casing provides earwigs with a favorite home. Earwigs and other small invertebrates can contaminate well water with bacteria, some of which may cause illness or disease. It's a good idea to have your well water tested each year for coliform bacteria. These bacteria normally do not cause illness or disease themselves, but their presence means other disease-producing microbes may be present.