These days it's not easy being a frog

Today I'm going to talk about the worldwide decline of amphibians.

First of all, what are amphibians ?

Amphibians are animals that can live both on land and in water. Generally they spawn eggs in water and their larva live in water. Sometimes adults are terrestrial, but still they have highly permeable skins so that they can absorb water through their skin. For example, frogs, toads, salamanders, and newts are all amphibians. Due to those features they are very sensitive to the change in water and air quality.

The Global Amphibian Assessment is the work of over 500 scientists from more than 60 countries over a period of 3 years. The study analyzed the distribution and conservation status of all 5,743 known amphibian species and was published in Science Express this October.

According to the study, 1,856 species which is almost a third, are now threatened with extinction. As many as 122 species may have died out since 1980. 43% of all amphibians are declining, 27% are stable, less than 1% are increasing, and the status of the rest is unknown. In some places, the numbers are staggering. In Haiti, 92 percent are threatened with extinction and 80 percent in the Dominican Republic. Jamaica, and Cuba also face similar peril. Although the picture is less bleak in the United States, at least 51 species are endangered.

So the question is what causes such a large scale decline ?

There are a variety of reasons for some losses, while others remain a mystery.

For example, in the United States and Europe, agricultural fertilizers run off into rivers and wetlands, causing deformities and reproduction problems.

A fungal disease is wiping out amphibians in large numbers in America, the Caribbean and Australia. Generally dry weather makes them susceptible to this deadly disease because it infects the skin of adult amphibians.
So, scientists believe the epidemic is worse in drought years and may be exacerbated by climate change. Now, many moist tropics are experiencing periodic droughts which may be the result of shifting worldwide rain patterns.

In the developing world, deforestation causes soil erosion and muddy water from erosion is often lethal to tadpoles because it kills the algae they feed on. 　And when wetlands are drained for human habitation, amphibians lose places to live and breed.

In Asia and south America, the marketplace is also one of causes. For example, in China, giant salamanders are considered a delicacy.

In conclusion it's no wonder that many species of amphibians are now on the brink of extinction. As they are vulunable to pollution and climate change, they are kind of "the canaries in the coal mine." And their impact on the food chain can also be a problem because they are important food for many birds and reptiles. You might remember the recent extinction of Japanese Crested Ibis, TOKI.

To reverse this global trend, we should start a campaign to preserve their habitat, tackle pollution, and also global cooperation is necessary to address issues of climate change.　 Captive breeding programs will also make a big difference.

In some parts of the world, conservationists have been working with local partners. In Sri Lanka, they are working to nurture forest damaged by dry climate and logging so that the forest can retain more rain water. 　This forest reconstruction plan will also prevent soil erosion, so people can grow crops and amphibians can live in humid conditions.

I hope it's not too late to save many of the most threatened amphibians as today's frog is tomorrow's man.

Thank you for your attention.

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