Stillwater News Press

April 12, 2014

Chorus frogs beginning to move to shallows

By Dwayne Elmore
Stillwater News Press

STILLWATER, Okla. — As warm spring rains begin to fill shallow depressions across Oklahoma, small frogs known as chorus frogs begin to move toward them. Once there, hundreds, or even thousands, of frogs emit a loud raucous series of calls in an effort to attract a mate.

Like other species of amphibians, they gather to take advantage of the brief window when their young can develop in the warm shallow water. Chorus frogs are some of the earliest of the frogs to begin calling, which can often be heard in February and March and are one of the harbingers of spring.

There are five species of chorus frog found in Oklahoma. Most people have heard of the spring peeper, which is a species found in extreme eastern Oklahoma. However, we also have the spotted, Cajun, boreal and Strecker’s chorus frogs in portions of the state.

While these tiny frogs are small in stature, up to a whopping 1.5 inches, they make up for it in voice. Their loud calls fill the dusky skies each warm evening in early spring and can often be heard hundreds of yards away. If you try to steal a glance at them by creeping to their breeding pools, they instantly go silent.

As they usually hide in dense vegetation along wetland borders, getting a good look is difficult.  Once chorus frogs have deposited and fertilized their eggs, the adults will spread back out across the landscape and continue their mostly hidden life.

While we may forget them outside of the breeding season, our actions greatly influence their abundance. Deepening of wetland edges, removal of wetland vegetation and introduction of predatory fish all reduce the number of chorus frogs in an area.

Most damaging is the draining of wetlands. The seasonally flooded pools, known as vernal pools, which harbor chorus frog young, are critical to many amphibian species. They are biological hot spots wherever they occur.

If you have these wetlands on your property, take the time to examine the diverse life they contain. You might be surprised at the species that have lived unnoticed. But each spring, as if to remind us they are there, they sing.

Dwayne Elmore is Oklahoma State University Cooperative Extension wildlife specialist in the department of natural resource ecology and management.