I read an article about chytridiomycosis.
Research shows that the fungus killing frogs around the world has almost certainly been distributed by trade in amphibians for zoos or private collections . Its origins are believed to lie in southern Africa. Chytrid is now found thoroughout the world and has exterminated a lot of species. The fungus kills amphibians by blocking cutaneous respiration. Rhys Farrer said "And it's obviously important, as chytrid is one one of the most devastating wildlife diseases with the largest host range of any, and responsible for dozens of species extinctions and many more extirpations of local populations."
In days of old, no-one knew there were any different lineages. However, scientists found three distinct lineages of the chytrid fungus in various nations. The major type has a truly global spread and was named BdGPL. Swiss sample was named BdCH. A third clade which turned up in the Cape Province of South Africa and the Mediterranean island of Mallorca was named BdCAPE. Their tests showed that BdCAPE was substantially less damaging to amphibians than BdGPL.
The genetic differences that make BdGPL more lethal have not been revealed. They think they are seeing unique evidence of recombination within BdGPL. It is not clear whether it's a hybridisation event but it's the most likely explanation. So they think it arose in the 20th Century, and that's in the realm of time for the trade in amphibians.
The team thinks that it is also worth investigating whether the less virulent forms can be used to save amphibians. In the same way, they may prepare viccines.
Some years ago, the fungus were discovered for the first time in Japan. It was a big news so I remember it. However, nevertheless it was regarded as a big problem, I don't know what happened in consequence.
I have studied about chytridiomycosis in Japan. In 2006, chytrid was regarded as a catastrophic diseases. However, it has been discovered that most of amphibians in Japan have a tolerance to chytrid.
Knowing about it, I had peace of mind for a while. However, chytridiomycosis is a big problem all over the world. I think it is the one of the problem of alien species.
Black, Richard. "Killer frog fungus 'spread by trade'." BBC Online. 8 November 2011. Web. 15 November 2011. <http://www.bbc.co.uk/news/science-environment-15624254>
My house in America is in the deep woods of Maine, which is a very rural state in the north east. Last summer, while I was there, in one day my son and I were cutting wood in the forest. On that day we found cute little snakes, a couple of salamanders, toads, and frogs. There were little tree frogs and a really big orange toad, and some other frogs. We were so happy because when an ecosystem has amphibians, then you know the ecosystem is healthy. This is because amphibians are very sensitive to their environment, so they cannot live in environments that are even a little unhealthy.
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