Global warming, pesticides, and deformed frogs

Worried that global warming and pesticides are causing frog deformities or decimating frog populations (maybe you're a fan of frog legs)? Fear not. Follow the basic principal that the media is not telling you something important in order to make a storey seem scary and you'll be right more often than not. Scary stories sell papers.

Here's just one example (there are others - follow the link to the full article):

Yellow-legged frogs of the High Sierra

Disappearance was blamed on:

The frog’s seemingly inexplicable demise has provoked much speculation in the media and among scientists, with parasites, ultra-violet radiation, fungal disease, and especially pesticides blamed for the frog’s troubles.

The real cause:

Folks had been stocking the lakes, rivers, and streams in the West with all types of fish, starting as early as the 1880s. As part of this action, trout were introduced into the glacial lakes of the Sierra Nevada and by 1924 wildlife biologists noted that mountain yellow-bellied tadpoles and trout were rarely seen in the same lakes. This continued with thousands of fingerlings being dropped by aircraft in high altitude lakes where there had been lots of frogs but not fish at all. (4) Guess what happened? The frog populations decreased.

Vance Vredenburg of the University of California at Berkeley began removing trout from five separate High Sierra lakes in the late 1990s. He saw frog population explosions.