Invasion of the Pill Bugs

Forrest M. Mims III

For reasons not fully understood, the pill bug population occasionally jumps to much higher than usual levels. This is has been one of those years around the Mims place on Geronimo Creek.

Pill bugs have always paid visits to our front porch since we moved to the country near Geronimo Creek 20 years ago. But never have we seen so many as during the past few weeks.

Neighbors up the road have not experienced a pill bug invasion. Perhaps our native landscaping is friendlier to pill bugs than those city grasses that refuse to grow on our place.

Pill bugs are the little gray creatures that often roll into a ball smaller than a pea when disturbed.

On many nights it has been impossible to walk a single step without crushing dozens of pill bugs.

We have had to keep a broom handy to sweep them away so we can go in and out of the house. If the pill bugs are not regularly swept away, you get to see your foot prints, which are soon outlined by pill bugs that gather to dine on their crushed colleagues.

If the pill bug tribe was trying to attract attention to itself, their local migration stunt has worked. Lately I’ve been researching them to learn more about their role in nature.

Many pill bugs roll up into a ball when disturbed. These are known as “rollers.” The remainder try to escape by walking faster than normal. They are called “hikers.”

Even very young children can do science projects using pill bugs. The simplest project is to collect a dozen or more pill bugs and determine how many are hikers and how many are rollers.

Some people call pill bugs wood lice or sow bugs. Scientists call them isopods.

Pill bugs normally eat decaying plants or even dead animals. The female carries her young in a pouch until they are mature enough to go about on their own.

Pill bugs are not insects. Because they are equipped with gills for breathing, they must live in areas with high humidity, such as under leaves, rocks or logs. This certainly does not explain why they have been gathering by the thousands on our front porch.

Pill bugs have many natural enemies, including spiders, frogs, toads and small mammals.

If pill bugs become a nuisance, you can easily capture them by placing half of a cantaloupe at their gathering site. I was surprised to see this old trick described on the Pest Control Canada web site.

Forrest M. Mims III and his science are featured online at www.forrestmims.org and www.sunandsky.org.