Pillbugs go by several different names depending on where you are and who you are talking to. Officially, they are part of a family of woodlice called Armadillidiida. You may hear them called roly-pollies, doodle bugs, potato bugs, sowbugs, woodlice, armadillo bugs, and of course pillbugs. These common names are all used for the same type of animal.
What are Pillbugs?
Pillbugs are actually a type of crustacean, not an insect. They are the only member of the crustacean family that has adapted to living on dry land. They are more closely related to water creatures such as shrimp or crayfish than to any insect. Pillbugs usually live in moist environments outside, but may end up in damp areas of buildings where there is a high humidity level, such as basements. They are often found in large populations around compost piles and similar areas where this is both high moisture levels and decaying organic material. Although these creatures are not the most pleasant to look at, the good news is that they don’t bite or sting, and they normally don’t infest foods or clothing. Pillbugs are herbivores, and feed mainly on decaying plant material, although they do sometimes feed on live plants.
How to Identify Pillbugs
Pillbugs are very easy to identify. They generally range in size from about ¼ of an inch to ½ of an inch. All types have a gray color, ranging from very dark to a lighter slate gray. They have oval shaped, segmented bodies that somewhat resemble an armadillo. The body is convex on the top, but flat or concave from the bottom. There are two antennae on the head that curve sharply back against the body. These tiny crawlers have 7 pairs of legs, and will usually roll themselves up into a ball as a defensive posture when disturbed.
The Life Cycle of the Pillbug
The female pillbug will produce about two dozen eggs, which take anywhere from three to nine weeks to develop and hatch. The mother has a pouch, composed of plates, on her underside where the young will stay for three to nine days after hatching. This process can be repeated two or three times per year. Pillbugs are also capable of reproducing by parthenogenesis (without fertilization from a male).
The young will molt four or five times as they grow, until they reach maturity, which takes approximately one year. Once reaching adulthood, the pillbug will usually live for another year. Their average lifespan from birth to death is about two years.
During their lives, molting occurs in two stages. The skin will split in the middle and the rear half is shed first. After a few days the front portion loosens and is shed as well. During this process they are extremely vulnerable and tend to stay isolated until it is complete. They have been known to eat their own kind during the molting process when the outer shell has not yet hardened.
Signs of A Pillbug Infestation
Pillbugs really don’t leave behind any sign of infestation other than their presence, and perhaps some minimal damage to plants. They are slow moving creatures, so they are easy to spot. They require a lot of moisture to survive. Most often, pillbugs that wander into an indoor environment will simply die from dehydration because the environment is too dry for them. They are also mainly nocturnal animals, avoiding light and sun which quickly dehydrates them. If they are in your home they will most likely be found in very humid and damp areas where there is some form of decay occurring. Outside the home, or in greenhouses, they are often found under bricks or walkway stones, in or under gardening pots, beneath mulch in gardens, in and around compost piles, and many other places that will shade them from the sun and help them keep moist and hydrated.