Field Study Reveals Surprising Snake‑Frog Predatory Interactions

Many interesting field research reports are published in professional journals such as Copeia, Herpetologica and Herpetological Review, and are not available on the internet.  From time to time I’ll provide summaries of some of the fascinating articles that I come across.  Today’s report, drawn from Autumn, 2010 publications, covers a favorite topic of mine – feeding records.  As theses reports show, snakes and frogs often do battle – and the results are hard to predict!

Fer-de-lance and Smoky Jungle Frogs: Venom vs. Poison

In Costa Rica, a Fer-de-lance partially swallowed and regurgitated a Smoky Jungle Frog.  The snake was rendered lethargic incapable of defending itself for at least 45 minutes (and would likely not repeat the experience!).  Smoky Jungle Frogs produce Leptotoxin, a powerful chemical that causes rapid death from cardiac arrest when administered to rats.  People have reported experiencing “tingling” sensations after handling Smoky Jungle Frogs.

Frog skin toxins can persist for surprisingly long times on some surfaces, and are real concerns in captive collections.  Years ago, a co-worker of mine transported a Pickerel Frog in a plastic bucket that was later used to house several Blomberg’s Toads (there is some confusion as to whether or not the bucket was thoroughly cleaned in-between).  Several Blomberg’s Toads died after a short time in the bucket; an autopsy showed evidence of toxin ingestion via the skin.

Cuban Treefrogs and their Prey

In Juniper, Florida, a Cuban Treefrog was observed consuming a Ring-necked Snake much larger than itself.  This introduced predator has also been known to take Florida Brown Snakes, and is likely causing problems for Florida’s native treefrogs, all of which are smaller than the Cuban.

A group of Cuban Treefrogs that I established in a greenhouse (Bronx, NY) subsisted largely on roaches and moths, but definitely also reduced the population of Green Anoles and House Geckos that shared their habitat.

American and African Bullfrogs are champion eaters…please see the video and article below for some interesting observations and footage.