Eastern Narrow-mouthed Toad
Gastrophryne carolinensis


The little Eastern Narrow-mouthed Toad (Gastrophryne carolinensis) is a small pointy-nosed frog of the southeastern United States.  It occurs from the east half of Texas up through eastern Oklahoma and then across through southern Missouri, Kentucky, and Virginia and south to the tip of Florida.  They are found in swamps, pine forests, wooded clearings, agricultural land or anywhere else there is moisture.  They typically spend most of their time under debris (logs, rocks) or underground in burrows where they can remain moist.  They only appear on the surface after heavy rains.


Like their western cousins, the Great Plains Narrow-mouthed Toad (G. olivacea),  the Eastern Narrow-mouthed Toad will call and breed in any shallow temporary water or the grassy edges of larger water bodies, particularly after heavy rains.  The night I made some of these recordings in Arkansas, I recorded a large number of these calling from the flooded grassy edge of a large lake and others calling from a flooded grassy ditch a few feet across with just a few inches of water next to the road.  The one thing Narrow-mouthed Toads seem to require for calling and breeding is shallow grassy water edges.


Like the other North American members of the family Microhylidae, these are small, chubby, pointy-nosed little frogs.  Like their Great Plains cousins, they also frequently show a fold of skin across the back of the nape.




The Eastern Narrow-mouthed Toad usually has a more prominent pattern than its western congener although this can vary.  The distinguishing character separating these two species is the patterns of their underside.  While the Great Plains Narrow-mouthed Toad has a generally unmarked, whitish or cream colored belly, the Eastern has a belly that is profusely mottled with black and white.  To me it generally appears black with whitish flecking.  You can see the belly pattern on the lower sides of the two G. carolinensis pictured here (and in the first picture).



The call of the Eastern Narrow-mouthed Toad is very similar to that of the Great Plains Narrow-mouthed Toad.  Both species have a long nasal "bleat" that is somewhat sheep-like.  To my ear, the Eastern Narrow-mouthed Toad is a nasal "maaaah" or even"baaah" sound.  (I will put together a separate post comparing the two with each other and the related Sheep Frog.)


Narrow-mouthed Toads can be difficult to find while they are calling because they usually call from dense grassy flooded areas, often right within clumps of grass.  Even when they are in the open, the often call with just the tips of their noses sticking above the water, like this individual picture below.  When you add that calling behavior to the fact that males are often less than an inch in length, they can be tough critters to spot while calling.




Here is the call of a group of three Eastern Narrow-mouthed Toads from Ouachita County, Arkansas, including the one pictured above. (The dry trills of the Cope's Gray Treefrog Hyla chrysoscelis are heard in the background.) 


The spectrogram of the loudest of those three calls shows a complex buzzy call typical of this genus.  This spectrogram includes two overlapping calls.


In another post, I will compare the calls of this Eastern and Great Plains Narrow-mouthed Toads.
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© Chris Harrison 2015

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