By Eric Duran
One of the classes we are offering at the Nature Discovery Center in late February is the Life in a Log class, in which we take kids out into the park to roll over rocks and logs and learn about all the tiny animals we find underneath. Many of these animals only come out at night or during wet conditions, and so most of us don’t encounter them very often. Many of these animals live beneath flower pots, stepping stones, and leaf litter as well, so have a good chance of encountering them in your own back yard.
Pill bugs (also called roly polys) are extremely common in forests and a variety of other ecosystems. They are so common, in fact, that they’re probably much more important to the ecology of their habitats than we realize. They feed on dead and decaying plants, animals, and fungi, and help decompose a lot of this organic material. Pill bugs are actually crustaceans (in the order Isopoda), and most of their relatives live in the ocean. They are the only common and widely dispersed group of land crustaceans. Though some of the flatter isopods (known as wood lice) are native to the United States, the common species that roll into a ball, which we find in the park and in our yards, were introduced from Europe.
Centipedes and millipedes are two closely related invertebrates, that get confused with each other all the time. Millipedes have long rounded bodies, four legs per body segment, and feed on decaying organic material (much like pill bugs). Millipedes can be somewhat poisonous (so if you’re somehow tempted, please don’t eat them), but are usually harmless to touch. Centipedes have long flattened bodies, long antennae, two legs per body section, and feed on other small animals. Centipedes are venomous. Even small species can deliver a painful little bite with their front venom pincers, so don’t handle them!
The most common frog that you’re likely to find in your yard, and hiding underneath logs, is the Gulf Coast Toad. Toads are essentially land frogs, with dry bumpy skin. Unlike aquatic frogs, toads have feet with unwebbed toes and a small structures (on the hind feet) which help them dig into the soil. Toads have a pair of large bumps behind the eyes, called paratoid glands, which may release a milky toxic substance, if the animal is seized by a predator. Though they are quite comfortable on land for long periods, they do need to lay their shell-less eggs in standing water. After heavy spring and summer rains, you may hear the males loud trills, calling the females to breed in drainage ditches, ponds, and even large puddles.
If you’d like to find out more about any of these animals, come join us on one of our guided nature hikes through the park, or sign your kids up for one of the preschool or elementary aged after-school classes about Life in a Log coming up in late February.
Duran is the staff naturalist at the Nature Discovery Center, 7112 Newcastle Dr., Bellaire, NatureDiscoveryCenter.org