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NATURE: Frogs: The Thin Green Line

Airs Wednesday, August 8, 2012 at 8 p.m. on KPBS TV

A frog’s bulging eyes allow it to see front, side and even partly behind.

Credit: Andrew Young/©2009 WNET.ORG

Above: A frog’s bulging eyes allow it to see front, side and even partly behind.

Frogs have been living on this planet for more than 360 million years, and over the centuries, evolved into some of the most wondrous and diverse creatures on earth. Today, however, all their remarkable adaptations and survival tactics are failing them.

Recent discoveries are startling: more than a third of all amphibians – most of which are frogs and toads – have already been lost, and more are disappearing every day. It is an environmental crisis unfolding around the globe, traveling from Australia to North and South America.

Interactive Map

Explore an interactive map of frogs around the world.

What You Can Do To Help

Educate Yourself: Learn more about frogs at your local aquarium or zoo. Natural history museums are also a good place to explore. Keep informed about legislation that affects your local frog populations. You can help frogs face threats like habitat destruction, global climate change and disease.

Protect the Environment: Watch what you throw away—and where you throw it away—to keep frog habitats trash-free. Don’t introduce non-native plants and animals. Reduce chemical use. The water table on which we depend collects a lot of the chemicals we flush down our drains or add to our lawns, despite our best efforts to treat the water. Don’t flush medicines down the toilet. Conserve water- the less water you use, the less has to be treated.

Support Conservation: Be hands-on, find a local habitat preservation or citizen science monitoring program. Or take part in a 24-hour BioBlitz near you. Put your money where it counts. Many environmental organizations (such as Amphibian Ark & Partners in Amphibian & Reptile Conservation), zoos and aquariums, scientific consortiums, and countless community groups are already tackling the global frog crisis. But there’s still a lot to do. Read more

Where the calls of frogs once filled the air, scientists now hear only silence. Ecosystems are beginning to unravel, and the potential to discover important medical cures may be lost forever.

Habitat loss, pollution and a human population that has doubled in the past 50 years have set the stage for their diminished numbers. But now, a fungus called chytrid has been identified as the major culprit, and so far the spread of the fungus can’t be stopped.

Chytrid continues to move quickly, extinguishing entire frog populations in a matter of months. Scientists have taken drastic measures to counteract it, such as evacuating frogs from the wild and sheltering them in a sterile environment.

The El Valle Amphibian Conservation Center in Central Panama, for example, houses 58 species of frogs in their facility, including the rare golden frog, which no longer exists in the wild. To date, the only chytrid-free area left in Panama is the Burbayar Forest, a thriving environment still full of healthy, unaffected frogs.

Frogs may seem small and insignificant, but their bodies may hold the key to important new discoveries in medical research. Scientists are finding that chemical compounds found in frogs’ skins can be used to treat pain and block infections, and are even being explored as HIV treatments.

Our chances for the discovery of future medical miracles may be slipping away with the disappearance of these tiny creatures in our midst.

Their impact on the world’s ecosystems is great. Frogs sit right in the middle of the food chain, and without them, other creatures are disappearing, too. We are only just beginning to understand what life may be like without them. The race is on to stem the tide – before the next frog crosses the thin, green line.

This program originally aired Sunday, April 5, 2009.

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Full Episode: Nature: Frogs: The Thin Green Line

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Video Excerpt: Nature: Frogs: The Thin Green Line

Tyrone Hayes and his students from the University of California at Berkeley are studying how agricultural chemicals, including fertilizers and pesticides, are affecting the health of frogs. Pesticides in runoff can cause an increase in stress hormones and lead to immunosuppression in frogs. In some cases Hayes has found that the presence of atrazine, a common agricultural chemical, can even cause frogs that are genetically male to develop as females and produce eggs.

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