Amphibian Conservation -- Frogs Matter
Think of frogs as good indicators of what’s happening in the environment.
Frogs have a body surrounded by a skin with some unusual properties. It holds the tissues and fluids in just like our skin but it is also porous, allowing both air and water to pass directly into their body without being filtered through the stomach. This makes frogs susceptible to any and all pollutants in the environment. Frogs are remarkable creatures, but there is a limit to the conditions they can adapt to.
Most frogs live both in water and on land at different stage of their lives, as tadpoles and as adults, so they’re affected by problems in both types of habitat. Since they take in water directly through their delicate skin, they’re very sensitive to water quality. Because of this sensitivity amphibians are considered a "canary in the coal mine'' for environmental damage.
Canary in a Coal Mine-Animal Sentinels
A warning to others….
The phrase living like a canary in a coal mine often refers to serving as a warning to others. The canary was used for detecting toxic or explosive gases in coal-mines, before there was a better way to do it. More sensitive to such gases than humans, they would collapse long before the miners were affected, and a collapsed canary was therefore a signal to the miners to get out immediately, and to management to look at the problem and clean up the mine.
Herpetologists (scientists who study amphibians and reptiles) are concerned about what's happening to the frogs, because the health of frogs is closely linked to the health of the environment. Frogs are extremely sensitive to water pollutants and acid rain. They can be seen as an early warning system of problems that may eventually affect the rest of us. “If chemicals in the water cause mutations and reproductive problems in frogs think what it could be doing to humans, “says Vicky Poole of the National Aquarium in Baltimore.” We can “help save frogs and other amphibians” by limiting the use of chemicals and pesticides which ultimately end up in the watershed and in turn harm the frog population. Hopefully, with a combination of conservation and study, we can help keep frogs hopping for another 190 million years.
Frogs are important for other reasons as well. Frogs and tadpoles consume huge numbers of insects—many of which cause crop damage and disease-and are themselves an important food source for many other species. Frogs have also played a huge role in medicine, research and medical applications.
A Fungus Brings Dinosaurs’ Fate to Amphibians
Ponds and swamps are becoming eerily silent as a mysterious killer fungus wipes out frog populations around the globe, a phenomenon likened to the extinction of dinosaurs. Like many other animals, they are affected by habitat loss and climate change, as well as pollution. But a special problem is a disease that’s spreading all over the world. A fungus of a type called the Amphibian Chytrid Fungus was discovered and named in the late 1990's. The fungus has now been found on every continent except Antarctica. The fungus is treatable in captivity using Itroconazole, a fungicide similar in chemical properties to Athlete’s Foot medication. Unfortunately, the disease is incurable in the wild, as fungicide cannot simply be sprayed into the rainforest.
Just where the fungus came from is a bit of a mystery, but the reigning theory at the moment points to the African clawed frog, which carries the fungus on its skin but is immune to its effects.
That type of frog has been distributed across the globe in recent decades because (here’s an irony) it is evidently quite useful in biology research — and also because it was handy for performing human pregnancy tests in the 1940s (much the way rabbits were used in earlier eras). Injecting the frogs with the urine of a pregnant woman induces the frog to produce eggs.
In any case, researchers theorize that the wide distribution and handling of the African clawed frog may, over time, have introduced the fungus into many environments where it was unknown before and where the local frogs are not immune to its ravages.
The fungus works like a parasite that makes it difficult for the frogs to use their pores, quickly causing them to die of dehydration. It has been linked to the extinction of amphibians from Australia to Costa Rica. When this fungus arrives in an area, 50 per cent in the area might go extinct within six months. Their rapid decline tells us that one of Earth’s most critical life support systems is breaking down.
In Yosemite National Park, the mountain yellow-legged frog is close to extinction. … The growing quiet along the park’s lakes is evident as many of the frogs are dying off. Some species affected by the fungus have been successfully bred in captivity, like the Panamanian golden frog. But fast action is critical if conservationists hope to reproduce this success.