Texas "Peepers"
Spring Peeper vs. Strecker's Chorus Frog

In this comparison post, I will be looking at two species of Chorus Frogs that overlap in the eastern part of the Lone Star State.  These two species are similar looking overall and although they probably aren't confused that often in the field, their calls are surprisingly similar.

The Spring Peeper (Pseudacris crucifer) is a small "treefrog-like" chorus frog of the eastern United States.  In many areas of the country it is the harbinger of spring as it starts calling very early in spring and its calls are so conspicuous around woodlands and even residential areas of the eastern US.

Spring Peeper (Pseudacris crucifer)
The Spring Peeper gets it common name for its "peep"-like call.  It get the species epithet crucifer from the x-shaped marking on its back (crucifer means cross-bearer).  Otherwise Spring Peepers are light brown frogs with a few markings on their upper surface around the X and typically a dark mask that runs from the nose through the eye.  A few Spring Peepers lack the back pattern but they usually have the dark mask.

Spring Peeper (Pseudacris crucifer)
The Strecker's Chorus Frog (P. streckeri) is a similar sized chorus frog of the central US.  It generally occurs in  oak woodlands and into grassy savannahs.  It will call from cultivated fields near woodlands as well.  In Texas, this species occurs in the eastern half of the state but its populations east of the hill country appear to have decreased significantly in the last 50 years.

Strecker's Chorus Frog is also a brownish frog with darker markings on the back.  The back markings can be somewhat  x-shaped similar to the Spring Peeper but they generally don't form a perfect x.  They also have a dark mask like the Spring Peeper, but the mask of Strecker's Chorus Frog tends to be a bit more narrow.

Strecker's Chorus Frog (Pseudacris streckeri)
DeWitt County, Texas
The Strecker's Chorus Frog is also a distinctly more stocky frog than the Peeper with a more massive body and stockier legs.  It is also more terrestrial than the Spring Peeper.  Spring Peepers often call from bushes and trees while the Strecker's Chorus Frog typically calls from the water or the ground near water.

Strecker's Chorus Frog (Pseudacris streckeri)
Guadalupe County, Texas

The two species overlap over a large area of far east Texas, although the Spring Peeper is a much more common frog within the area of overlap.  Strecker's Chorus Frog can be locally common but it is apparently absent from large parts of its former range.  In the hill country it is still reasonably common along canyons and creeks.

This map is adapted from the Herps of Texas website maps, although I have taken the liberty of filling in some counties where the species would be expected but haven't been recorded yet.

Even though Pseudacris crucifer is called the Spring Peeper, both of these species will call during the winter here in Texas as long as the temperatures are above freezing.  Spring Peepers usually finish breeding in March in Texas, Strecker's Chorus Frogs will breed well into April and even May depending on rains.

The two frogs are somewhat similar looking in general color pattern and overlap in at least certain parts of the state and they also both have a similar loud peeping call.

The call of the Spring Peeper is a distinct, loud, whistled peep that carries a long distance.

The Strecker's Chorus Frog on the other hand is a more percussive "tink" sound.  It sounds a bit like someone striking a metal pipe with a small metal hammer.

In a large chorus, the calls are more similar but can still be distinguished by listening for the whistled vs. percussive nature of the individual calls.

Here's a chorus of Texas Spring Peepers -

Spring Peepers from the Davy Crockett National Forest, Texas

And a recording of a Strecker's Chorus Frog chorus from Dewitt County, Texas-

Pseudacris streckeri - chorus from DeWitt County, TX

So next time you are in far east Texas in the spring and hear a tink or peep from the forest edge, it might be worth a closer listen.

© Chris Harrison 2017

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