Gray Treefrog
Hyla versicolor

The Gray Treefrog (Hyla versicolor) is a common treefrog of wooded areas in the eastern half of North America.  As the common name implies, it is a "gray" frog and is usually found in wooded areas often low in trees and bushes.
Although it is called the "gray" treefrog, its color varies from light whitish gray to dark gray or from brownish gray, tan or even bright green.  It usually has a pattern of markings on its skin to give it a pattern that helps it blend in to the bark of trees.  Again the pattern can be gray on gray, gray on whitish, gray on green, brown on tan or brown on green.   A few individuals show so little pattern that they appear almost uniform light whitish gray or solid green backed.   They usually have some yellow on the hind limbs that helps you identify these patternless frogs.

Gray Treefrog (Hyla versicolor)
Grimes County, Texas
Although the species is quite common across much of its range, the actual range of the species is hard to delineate because there is an identical species of gray treefrog, Cope's Gray Treefrog (Hyla chrysoscelis) that overlaps over much of the range.  While the two species differ in the number of chromosomes and their calls, they are indistinguishable in external appearance.   Because of this, the range of the two species has been intertwined.  Most field guides tend to make a combined range map for "Gray Treefrog (H. versicolor and H. chrysoscelis)" to get around this problem.  In recent years, efforts have been made to help define the range and overlap of these two species with more precision.

Fortunately, when they are calling the two species are pretty easy to distinguish.  Cope's Gray Treefrog (H. chrysoscelis) has a dry rattling trill while the Gray Treefrog (H. versicolor) has a slower, more bird-like trill.  I have several blog entries for Hyla chrysoscelis and Hyla versicolor that compare the two species.

Gray Treefrog (Hyla versicolor)
Houston County, Texas

Here is a cleaned up version of three calls from an Gray Treefrog from Colorado County, Texas. The call was "cleaned" to remove some of the other species calling in the same pond.



Here is the spectrogram from that recording.  The white marks represent the treefrog's call.



Here is another recording of a Gray Treefrog (H. versicolor) from Colorado County, Texas.
Great Plains Narrow-mouthed Toads (Gastrophryne olivacea) can be heard in the background.




Here's a short video showing two individual Gray Treefrogs calling the Davy Crockett National Forest near Lufkin, Texas.

video


© Chris Harrison 2012


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