14 May 2004

Pill bugs

Forrest M. Mims III

Pill bugs are enjoying a population boom along Geronimo Creek in South Texas. They're scattered all through the woods, especially under and around rotted logs and anywhere leaves have formed a layer over the soil.

Pill bugs sometimes become bored with their normal habitat in the woods and in the flower beds and yards that have invaded their territory. That's when they go exploring. Our front porch is an especially popular place for pill bugs to promenade, which they do all night long.

If they would simply read a few of the many articles about them, they would realize they are supposed to live in damp places and stay off our porch.

Every evening I sweep them back where they came from. They don't mind. They just roll up into perfect little spheres and enjoy the ride. Within a few hours, they have paraded back to the porch. Some even climb up the brick walls.

While most people call them pill bugs, they are also called doodle bugs and rolly pollies, which has various spellings.

Sow bugs are very similar in appearance, but they do not roll up into a ball when disturbed.

Pill bugs are really not bugs or insects. Biologists refer to them as terrestrial (land-dwelling) crustaceans. That's because they resemble crustaceans like shrimp and crayfish that live in water. There are various species of pill bugs, and they are all classified under the genus Armadillo. Lest this name raise questions, pill bugs are not cousins to those armadillos that frequently plow their way through Texas yards and fields.

Pill bugs bear live young, which the mom keeps in a pouch on her belly until they are ready to leave. Their natural enemies include frogs, toads, spiders, small mammals and people.

Pill bugs can sometimes be a nuisance if they live where you do. Yet they serve a very important roll in recycling the plant litter in your flower beds and yard. So I'm not going to tell you how to kill them.

Just sweep them away when they invade your porch. You might want to name them first. Those that have time to morph into a ball will soon be back.

Forrest M. Mims III and his science are featured online at http://www.forrestmims.org/.

This feature was originally published in Forrest Mims's weekly science column in the Seguin Gazette-Enterprise, Seguin, Texas. The column is written for a general audience.