Ornate Chorus Frogs

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            On rainy nights in late fall and winter, small wetlands across the Coastal Plain of the southeastern U.S. come to life with the frantic calls and movements of winter breeding amphibians.  Many amphibian species breed in seasonal wetlands that are most commonly inundated during predictable fall and winter rains.  These wetlands provide ideal breeding habitat, free from fish and other large predators, with plentiful food sources for tadpoles and larval salamanders.  At peak times in healthy wetlands, the breeding choruses of Ornate Chorus Frogs (Pseudacris ornata), Southern Chorus Frogs (P. nigrita), Little Grass Frogs (P. ocularis), Spring Peepers (P. crucifer), and Southern Leopard Frogs (Rana sphenocephala) can be deafening.  It’s a wonder that a female frog of any species can select a calling male worthy of her attention.

            Of all the winter breeding anurans in southeast, Ornate Chorus Frogs are the most strikingly colored, with a background color that can range from bright green to reddish-brown to a metallic silvery-brown.  They have a prominent dark stripe through the eye that often continues somewhat intermittently down the body.  The limbs are often striped, and the back legs hide patches of yellow coloring near the end of the body.  Individuals of various color patterns can be found in the same population, with green and brown individuals often calling side by side.  Calling Ornate Chorus Frogs sound similar to other chorus frog species, giving a fast-paced peep or pip sound that is often repeated in rapid succession.  Males usually begin calling to attract females sometime in December and will be mostly finished by sometime in March.

            Once a calling male successfully attracts a female to his location, eggs are deposited in small clusters (approximately 20–40 on average) that are attached to submerged vegetation. Eggs quickly hatch and tadpoles then remain in the wetlands for several months before metamorphosing into adults.  Ornate Chorus Frog tadpoles stand out from other tadpoles, which are often difficult to identify.  Their tail fin has a broad arch that comes down right behind the eyes on the top of the head, and they generally have two golden stripes running along the back from eyes to tail.  Metamorphosing individuals resemble miniature adults but lack some of the bright colors that adults possess.  Newly metamorphosed individuals migrate away from breeding wetlands to surrounding uplands where they will grow into adults, reaching a maximum size of 1–1.5 inches.  Little is known about the terrestrial portion of Ornate Chorus Frog’s life cycle because they are difficult to find during the non-breeding season.

            There is increasing conservation concern surrounding Ornate Chorus Frogs (and many other winter breeding amphibians).  The southeastern U.S. has experienced severe loss and degradation of both wetland and upland ecosystems over the last two centuries.  There have been notable declines of Ornate Chorus Frog populations in several states throughout their range, and extant populations are likely still negatively impacted by poor habitat quality and poor management of existing wetlands.  However, this species is still locally abundant in certain areas, especially in Georgia and Florida.  While traveling around the southeast on rainy winter nights keep your eyes and ears open for these wonderful anurans of the Longleaf Pine ecosystem.