More than most other groups of animals or plants, amphibians have suffered terribly in recent decades. Their permeable skin and general preference for the very wetlands that humans seak to drain and destroy have left them vulnerable to a wide range of attacks from habitat destruction to an insidious fungal infection known as chytridiomycosis that seemingly is fatal to frogs and toads (though the fungus and the infection itself are still little understood). The general result has been a massive wave of extinction not seen in a major vertebrate group in recorded history. Most of the seeming extinctions have come about as frogs in vulnerable tropical areas have fallen victim to a combination of chytridiomycosis and habitat loss, though other groups of amphibians, including temperate frogs, toads and salamanders have all suffered as well.
Here is a link that highlights 10 "lost" species of amphibians that may have left our midst forever.
There have been "rediscovered" species of amphibians that were percieved to have gone extinct, so some hope may remain for some of these species. However, now that it has already happened, let us take the example of the vulnerable amphibians as our proverbial "canary in the coal mine" and realize that if we have made the world unsafe for our fellow vertebrates, what are we doing to ourselves?