Houston Toads: What Are Those Bumps?!

One of our Leon county toads, Red, paused chasing crickets for moment for a quick photo op. She is quite the photogenic toad!

Have you noticed in our Houston toad photos the large, lump-like structure behind the eyes? This structure is not a lump or a wart; it is in fact a specialized gland called the parotid gland. This gland is responsible for producing toxins that protect the toad against predators. Different toads produce different toxins of various “strengths.” In general, these toxins are not dangerous to humans; however, the cane toad (Bufo marinus) produces a toxin that can cause some skin irritation. Has your dog ever picked up a toad, then started foaming at the mouth? It is a reaction to these chemicals that the toad hopes will distract the unlucky pup so it will have a chance to get away!

The size and location of the parotoid gland can also be used to tell the difference between different species of toad. A good resource can be found here: Know Your Toads.

Did you know several compounds made by the skin of amphibians, specifically frogs, are currently the focus of a great deal of biomedical research? Several studies have found that many of these compounds have anti-microbial properties which have led some researchers to believe that they might be used to make the next generation of antibiotics. Additionally, a compound produced by the skin of the green-eyed tree frog (Litoria genimaculata) may be able to stop infection by the HIV virus, the virus that causes AIDS.

It is estimated that ~32% of all amphibian species are threatened with extinction.  Who knows what amazing medical breakthrough is waiting to be discovered on the back of a frog or toad? Now more than ever it is critical that we join together to help save these amazing creatures!

 

For more reading:

http://jvi.asm.org/content/79/18/11598.full.pdf+html

http://www.natureserve.org/library/amphibian_fact_sheet.pdf



Search Blog & Website
Subscribe to Houston Zoo News
Get the latest stories and updates from the Zoo in your inbox! Find out how: Houston Zoo News
Houston Zoo Facebook Page