Frog and toad populations have been declining everywhere, partly because of habitat destruction, partly because of toxic chemicals like pesticides in the environment, and partly because of a fungus that’s still puzzling scientists.

But here’s another factor: scientists in Hawaii have published a study in the journal Environmental Toxicology and Chemistry showing that ground level ozone might be sickening frogs, too.  Ground level ozone forms when sunlight heats up chemicals from exhaust fumes, basically. And while we don’t see lots of frogs hopping around tail pipes in downtown Louisville, they do live close enough to be affected.  The researchers found that short term exposure to ozone caused toads to lose their appetite and not move around so much, as if they were depressed.

Amphibians, they say, are more susceptible to ozone because their skin, as well as their lungs, breathes.  It’s permeable.  That also means frogs and toads are another of what we call “sentinel” species – the canaries in the coal mine when it comes to environmental pollutants.  Read an abstract of the study here.
Golden Toad, public domain image from the U.S Fish and Wildlife Service