University Park, Pa. -- Lungless salamanders may join fish and stream bugs as indicators of the environmental health of small streams, according to Penn State researchers.
"In general, amphibians, are thought to be good ecological indicators and frogs and toads are often used for this purpose," says Gian L. Rocco, Ph.D. candidate in wildlife and fisheries science. "Stream dwelling salamander populations are considered generally more stable than temporary pool breeding amphibians and may offer another biological tool to assess stream habitat quality, especially where fish and bugs are absent."
While wildlife experts monitor streams for acidity, temperature and pollutants directly, these factors say little about how environmental degradation affects animal populations. Because these salamanders are lungless, breathing through their skin and the linings of their mouths, they can be very sensitive to changes in their aquatic and terrestrial environments. Also, some species lay eggs on land while others lay eggs in the water. These differences, among others, may make some species more sensitive to waterborne pollutants than others.
Lungless salamanders are abundant and widespread; serve as both predators and prey; and lead both aquatic and terrestrial lives. With so many different habitat and breeding requirements and possibly varying tolerances for levels and types of pollution, lungless salamanders are choice amphibians to monitor stream community health.
"Four species of lungless salamander appear to be sufficiently abundant and widespread in Pennsylvania to qualify as potential bioindicators," Rocco told attendees today (June 25) at the 1999 joint annual meeting of the American Society of Ichthyologists and Herpetologists, American Elasmobranch Society, Herpetologist's League and the Society for the Study of Amphibians and Reptiles held at Penn State's University Park campus.