Adult Chorus Frogs are small, brown or gray, with three dark stripes running down the back. Though the dorsal color of most is light brown or gray, I have seen some individuals with a brighter, brick-colored dorsum. Ventral color is light. They can usually be distinguished from Spring Peepers, Pseudacris crucifer, by the "X" mark that the latter possesses. Chorus Frogs can attain lengths of just over one inch, although most adults are smaller (Minton 119).
Eggs are laid in masses of up to 240 eggs, usually attached to aquatic vegetation (Minton 121). Tadpoles are small and dark, with some mottling. The color of the tail musculature grows lighter as it gets closer to the tip (Minton 118-119).
Minton describes the call of these frogs as a "creeek-crick." This call becomes high pitched and louder through its duration--just two or three seconds (Minton 120). A chorus usually starts with one or two individuals, but when it reaches its loudest point, this chorus can be nearly deafening. Listen to the call courtesy of the Indiana DNR.
Ecology and Conservation
This species inhabits wet meadows and swamps. The can often be found around temporary pools of water (Minton 119-120). This species is difficult to find outside of the breeding season, though it can occasionally be heard calling during summer or fall rains. Chorus Frogs feed on a variety of invertebrates, from spiders to beetles.
Breeding for this species occurs from February to late April in shallow bodies of water, which are often temporary pools. Presence of some aquatic vegetation seems important to breeding site selection (Minton 120). Chorus Frogs begin calling in February and continue through April (Minton 120).
The Pseudacris triseriata species complex is widespread across the eastern United States, the Great Plains, and into Canada. One member of this group can be found throughout the state of Indiana. The Western Chorus Frog (P. triseriata) is widespread throughout the state, while the Boreal Chorus Frog (P. maculata) is likely restricted to northwestern or western Indiana.
Indiana's Chorus Frogs belong to the Pseudacris triseriata species complex, which were once described as several subspecies of a single species. A phylogenetic study by Lemmon et al. (2007) suggested that two currently recognized species--the Western Chorus Frog (P. triseriata) and the Boreal Chorus Frog (P. maculata) likely occur in Indiana. See the Distribution section above for more details on where these species likely live in Indiana. 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.
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.
Lemmon, E. M., A. R. Lemmon, J. T. Collins, J. A. Lee-Yaw, and D. C. Cannatella. 2007. Phylogeny-based delimitation of species boundaries and contact zones in the trilling chorus frogs (Pseudacris). Molecular Phylogenetics and Evolution 44:1068-1082.
Minton, S. A. Jr. 2001. Amphibians and Reptiles of Indiana. Indiana Academy of Science, Indianapolis, IN.