American bullfrog predation upon toads and bats

[findiviglio]

Recently I was prompted, by a question posted to one of my articles (http://blogs.thatpetplace.com/thatreptileblog/), to look into incidences of American bullfrog predation upon toads (Genus Bufo/Anaxyrus). I thought I might pass along the results of my rather quick search.

A Herpetological Review (2003) article documenting 2 cases of American bullfrogs (Rana catesbeiana) consuming adult Bufo nelsoni in Nevada. In one instance, the bullfrog may have eaten the toad as long as 11 days before the bullfrog was euthanized and dissected, yet appeared in good health, i.e. unaffected by skin toxins (up until it was euthanized by the researcher, that is!).

The only other case of frog predation upon toads that I turned up involved Oregon spotted frogs, Rana pretiosa, consuming young B. boreas (regularly) in Oregon.

This past summer, NY DEC magazine The Conservationist ran a photo of an American bullfrog in the process of swallowing a bat. Of course all sorts of related anecdotes abound, but this is the first related photo I have seen. The largest prey item I have personally observed taken by a bullfrog was another bullfrog. As had been my habit, I was tossing crickets to the bullfrogs that had taken up residence in an artificial pond outside the Bronx Zoo’s Jungleworld, where I worked at the time. One bullfrog leapt at a cricket and landed directly in front of a larger animal, and was promptly swallowed (but not without a good deal of squirming and cramming)…all this in front of a large group of second graders who had stopped to watch! I knew the larger frog by sight…despite a meal that equaled about half his mass, he was back snapping up crickets within 2 days or so.

Best regards, Frank