Image from CDC website on emerging infectious disease
Also via boingboing today, news regarding a fungus (Batrachochytrium dendrobatidis) that is killing frogs and other amphibians around the world. The fungus causes severe skin infections in every amphibian species it attacks, and the high mortality rate may lead to extinction for many species. Of course, the more mundane threats to amphibian populations still apply:
While the spread of the disease is a major new threat to all amphibians, the scientists reported that the greatest current danger to every threatened species is still the loss of habitat as cities and suburbs expand, streams and ponds and wetlands give way to the needs of farmers, and forest lands are destroyed.
It is further reported that global warming and the attendant lowering of immune response in amphibians may exacerbate the fungus-related problems. See the article "Widespread amphibian extinctions from epidemic disease driven by global warming" published in Nature on 12 January 2006.