Adult Spring Peepers are small frogs. They are usually tan, orange-ish, or brown in color, with a distinctive "X" pattern dorsally, and a white ventral surface. Sometimes the dorsal X is obscured or misshapen. The legs are usually banded. Spring Peepers generally grow to around 1 in (20-30 mm) total length though there is noticeable variation with adults from the northern part of the state growing larger than those from the south.
Females deposit eggs in small, clumped masses of 800 to 1,000 individual eggs. A small and dark tadpole that grows to around 1 in (~25 mm) long. The tailfin is clear with dark mottling around the edges.
Spring Peepers are most easily distinguished from Chorus Frogs (Pseudacris triseriata complex) by their dorsal pattern. Chorus Frogs have either dorsal stripes or blotches while Spring Peepers have an X-shaped pattern. They differ from Blachard's Cricket Frogs (Acris blanchardi) in that Spring Peeper skin is smooth instead of granulated and they lack the dark triangle that Blanchard's Cricket Frogs have between their eyes.
Spring Peepers have a high pitched single note "peep" call. This note is repeated roughly every second. Listen to the call courtesy of the Indiana DNR.
Ecology and Conservation
Upland forests and marshes are the favored habitat of this species, but open fields and grasslands are also used. Spring Peepers appear to be relatively common in suburban and rural areas provided there are wetlands or small pools present. Spring Peepers are most active during rainy weather in the spring, but may be found active anytime from March to November. Like many other frogs, Spring Peepers are able to withstand freezing temperatures for a period of time. Spring Peepers feed on a variety of small terrestrial invertebrates.
In Indiana, this frog utilizes vernal pools, roadside ditches, flooded fields, and marshes for breeding. While Chorus Frogs (Pseudacris triseriata complex) prefer shallower, ephemeral pools, Spring Peepers appear to do better in more permanent wetlands. Amplexus often takes place under water, where the females attach their eggs to small twigs and the males fertilize them externally. Males will often call from higher perches on emergent vegetation, shrubs, and small trees. Spring Peepers may call periodically throughout the fall and winter, but do not start breeding until the first warm rains of spring. In southern Indiana, January and February rains may initiate breeding activity. Breeding generally lasts into April or May. Eggs take a week or more to hatch and the larvae generally transform during June or July.
Spring Peepers appear to be doing reasonably well throughout the state and they oftentimes persist even in small woodlots in and around suburban areas. Additionally, Minton states that "its numbers seem to have increased since 1970, particularly in the southwestern counties".
Spring Peepers are found throughout much of the eastern United States and Canada, but are absent from most of Florida. Spring Peepers are widespread and common throughout Indiana and likely occur in every county.
Some scientists recognize two subspecies of the Spring Peeper (Pseudacris crucifer); under that taxonomy, Indiana is home to the Northern Spring Peeper (P. c. crucifer). These frogs are members of the family Hylidae, which is a globally diverse group and is represented by a total of 6-7 species in Indiana.
Austin, J. D., S. C. Lougheed, L. Neidrauer, A. A. Chek, and P. T. Boag. 2002. Cryptic Lineages in a Small Frog: the Post-glacial History of the Spring Peeper, Pseudacris crucifer (Anura: Hylidae). Molecular Phylogenetics and Evolution 25:316-329.
Brodman, R. 2003. Amphibians and Reptiles from Twenty-three Counties of Indiana. Proceedings of the Indiana Academy of Science 112:43-54.
Conant, R. and J. T . Collins. 1998. Reptiles and Amphibians of Eastern and Central North America. Third Edition, Expanded. Houghton Mifflin, New York, NY.
Klueth, S. and J. Mirtl. 2013. Pseudacris crucifer (Spring Peeper) Geographic Distribution. Herpetological Review 44:270-271.
Layne, J. R. Jr. and J. Kefauver. 1997. Freeze Tolerance and Postfreeze Recovery in the Frog Pseudacris crucifer. Copeia 1997:260-264.
Minton, S. A. Jr. 2001. Amphibians and Reptiles of Indiana. Indiana Academy of Science, Indianapolis, IN.
Pierson, T. 2012. Pseudacris crucifer. Spring Peeper. Geographic distribution. Herpetological Review 43:301.
Skelly, D. K. 1996. Pond Drying, Predators, and the Distribution of Pseudacris Tadpoles. Copeia 1996:599-605.