Originally created 04/21/01

Amphibian decline stirs concern



FAIRVIEW, Tenn. - The animals that live in Lisa Powers' yard - three dogs, five cats, one peacock and 21 guinea fowl - are the tip of the iceberg compared to what's inside the house.

Lizard-wise, there are two iguanas, two velvet day geckos, two blue-tongue skinks, 13 leopard geckos, one leaf-tail gecko, eight crested geckos, two frilled dragons, three Standing's day geckos and six bearded dragons.

A lifelong naturalist with an extensive background in herpetology, Powers adopts reptiles and amphibians the way some people rescue stray dogs. Her home just west of Nashville is a refuge for creepers and crawlers.

She has a black pine snake that was confiscated in a drug raid, and the circular walls of her house - a 4,400-square-foot geodesic dome - are lined with custom-made terrariums inhabited by pythons and boas.

"People get lizards and snakes and don't realize the care they require," Powers said. "For example, right now I have a blue-tongue skink that needs its nails trimmed."

Lately Powers has turned her attention toward frogs and toads - or, more specifically, to their calls.

This year she became the new state coordinator for the Tennessee Amphibian Monitoring Program, an ongoing survey of the state's frog and toad populations that's administered by the Tennessee Wildlife Resources Agency.

At the backbone of the program is a body of "froglegger" volunteers who identify frogs and toad calls by listening to their calls along established routes.

Powers said about 80 volunteers across the state are helping biologists get a clearer picture of the long-term population trends of Tennessee's frogs and toads.

"There's a lot of concern about the worldwide decline of amphibians but very little baseline data to tell us exactly what's happening," Powers said. "The loss of wetlands obviously plays a big role, but pesticides and pollution are contributing, too. Frogs have porous skin, and like all amphibians, they're extremely sensitive environmental indicators."

As with songbirds, the best time to hear toads and frogs is during the breeding season when males are trying to attract females to a breeding site, be it pond, ditch or backwater slough.

Powers said the wet weather this spring has made the frogs around her place especially active.

On a recent afternoon, while sitting beneath an oak tree in her front yard, she stopped in mid-sentence to tell a visitor that the throaty trill that had just emanated from the nearby woods was in fact a gray tree frog, not songbird.

"I really like listening to tree frogs in the summer," she said. "Their call is so melodic."

Powers has embedded half-a-dozen plastic swimming pools in the ground around her house and filled them with water and aquatic plants to serve as frog habitat.

Powers is a firm believer in biological pest control. She said her guinea fowl keep the tick population down, and she puts pieces of bark and pottery around her garden to provide cover for American and Fowler's toads, which also help control the insect population.

"A toad," she said, "is actually a type of frog, just drier."