There appears to be new interest in the demise of frogs and toads around the world, centering upon the theory that climate change has contributed to the spread of a deadly fungal skin infection. Several articles I have read mention one of the most famous extinctions, that of the golden toads which once appeared in large numbers in the Monteverde cloud forest in Costa Rica.
When I was in Costa Rica a couple of years ago, I stayed at a bed and breakfast owned by a family whose ranch had been purchased and incorporated into the nature preserve at Monteverde. Their son described how one year the toads had appeared in their usual number, and the next year they were gone. He stated that this coincided with some work performed within the toad's breeding area. He left the firm impression that the most likely cause of that toad's extinction was not global warming or a spreading fungus, but instead was the result of changes made to their breeding area. It is safe to assume that any such changes would have been made with the best of intentions, but perhaps with the worst of consequences.
It's not that disease isn't an issue, or that global warming cannot be part of the equation. But we're not speaking here of a gradual disappearance - it was a sudden extinction, associated with a cessation of breeding:
In 1987, the golden toad was closely studied by an American ecologist and herpetologist who, by chance, happened upon its breeding spectacle. She described it as brief and breathtaking; the males looked like "little jewels on the forest floor." She was so fascinated that she applied for a grant to return and study the toads.Although that article discounts habitat destruction as a cause of the extinction,
In 1988, no toads appeared when the seasonal rains started. During several months of searching the Monteverde forest, scientists found only ten golden toads, and none were breeding. In 1989, only one lonely toad was found where once there were hundreds. Despite much searching, not a single golden toad has been seen since then.
Habitat destruction does not explain the disappearance of the Monteverde golden toad, however. The high-elevation rain forest where it lived is a relatively pristine area, protected as a national reserve since the 1970s.You don't have to do all that much traveling in the developing world to find examples of architecture, natural resources, or other attractions being damaged or destroyed in the course of well-meaning preservation efforts. (And you probably wouldn't have to look very hard to find similar mistakes in the developed world.)
I do not mean to diminish the significance of climate change to animal populations, particularly in an environment such as a cloud forest, and I certainly don't mean to diminish the importance of conservation efforts. It's more that I think that in many contexts we need to recall that the road to hell can be paved with good intentions.