Amphibians in Decline
DB: This is Earth and Sky. Since the 1980s, an unusually large number of amphibians have been dying all around the world.
JB: About 20 species are thought to have become extinct. There’ve been declines in more than 200 species. But no one knows what’s going on. Consider the ponds of California’s Sierra Nevada Mountains. They’re a lot quieter these days because croaking frogs and toads have been dying off. Some scientists blame airborne pesticides drifting from valley farmlands. Others point to introduced species of trout that consume millions of tadpoles. Still others think it’s just the natural fluctuation of animal populations.
DB: But die-offs are happening globally – even in places largely untouched by human activities. One global concern is the thinning of the ozone layer and consequent increase in harmful solar radiation. Amphibians’ sensitive skin might make them especially vulnerable.
JB: Acid rain, pollution, habitat loss, global warming – they all might be factors. What’s more, some believe that amphibians might be the “canary in the coal mine” – that is, the demise of frogs, toads, salamanders and newts around the world might be a first signal of serious environmental change to come.
DB: That’s our show – special thanks today to the National Fish and Wildlife Foundation, and to the U.S. Forest Service. We’re Block and Byrd for Earth and Sky.
The following individual(s) were interviewed for today’s show. Our thanks to:
Cheri A. Ford
Wildlife Program Manager
Eastern Region, USDA Forest Service
Bruce A. Kingsbury, Director
Center for Reptile and Amphibian Conservation and Management Science Building
Indiana-Purdue University
Fort Wayne, In
The following books, articles and web sites were used in preparing this script:
“Amphibian deaths in the Sierra may signal a serious threat”, Fresno Bee, Monday, July 02, 2001
Blaustein, Andrew. “Amphibian mortality linked to climate change.” April 01, 2001
Partners in Amphibian and Reptile Conservation – Midwest Group
Frogs.org (Amphibian Conservation Alliance)
Additional Teacher Resources
National Biological Information Infrastructure, FrogWeb: FrogWeb: Amphibian Declines & Malformations
This website focuses solely on the reasons for and scientific repercussions of the decline in amphibian populations around the world. The site is set up with links to several different pages of information on various subjects concerning amphibian population decline.
U.S. Geological Survey, Northern Rocky Mountain Science Center: Understanding Reasons for the Decline of Amphibian Population
This site provides information on amphibian research and monitoring, the amphibians of Glacier National Park, and the effects of global change on North American amphibians.
Nature, Nature Highlights: Ecology: Amphibian Populations in Decline
Amphibian populations have suffered widespread declines and extinctions in recent decades. Although climatic fluctuations, increased UV-B radiation, and increased prevalence of diseases have all been implicated at particular localities, the importance of global environmental change remains unclear. This article and its corresponding links explore the importance of discovering the reason for the declines and extinctions in international amphibian populations.
