Giant Toad
Rhinella horribilis

OK, so this blog post is going to start off with a correction to a previous blog post.   My previous blog post about the Cane Toad (Rhinella marina) discussed the Cane Toad as being a species native to Texas, Mexico, Central America, South America and introduced to a variety of places worldwide.  But a recent study based on mtDNA and skull morphology has shown that this "species" is actually two species of toad!  So I am changing my old blog record to cover Rhinella marina and will make a new post for the Texas species, Rhinella horribilis.

The Giant Toad (Rhinella horribilis) is a massive toad occuring from South Texas down into Mexico, Central America and along the northwest coast of South America (west of  the Andes).

Giant Toad (Rhinella horribilis)
Costa Rica

In Texas, this species is restricted to the lower Rio Grande Valley, occurring along the river and inland from Laredo down to the mouth of the Rio Grande.  In South Texas it is a fairly common species.

Adult Cane Toad
Chiapas, Mexico
These are massive toads. Adults have exceeded 5 pounds in mass and been over 15 inches long.

The call of the Giant Toad is actually what you would expect for a huge toad.  Toads generally have trilled calls.  Smaller toads have faster, high-pitched trills and big toads have slower, low-pitched trills.  The bigger the toad the lower pitched the trill.  The trill of the Giant Toad is so slow and low pitched that it is drum-like.  This individual was from north of Aguas Zarcas, Costa Rica.

Here's a slightly longer section of call from an individual near Caño Negro, Costa Rica.

Giant Toad call from Caño Negro, Costa Rica

And here's my only recordings of Texas Giant Toads.  This is a chorus of individuals calling from a resaca in Hidalgo County, Texas.

Giant Toad call from Hidalgo County, Texas

Here is a short recording of some Giant Toads from Campeche, Mexico

© Chris Harrison 2017

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