Before it sings its distinctive throaty notes, a Western chorus frog puffs its throat pouch
March 30, 2014
After the long, brutal winter, the spring explosion of frogs has been especially welcome.
March is the transitional period when Mother Nature struggles to throw off the shackles of winter. Bit by bit, the days lengthen, and warm and icy waterscapes thaw.
The frogs aren’t a species to be contained. With even the faintest hope of open water, frogs emerge from hibernation and set to song.
Leading the charge are Western chorus frogs and spring peepers. The two species create a distinctive wall of sound in our wetlands. The tiny peepers’ shrill birdlike whistles fill the air, and a vociferous pack can be heard from great distances.
Mixed with the peepers are the distinctive throaty notes of Western chorus frogs. The male puffs his elastic throat pouch to impossible dimensions. It is as if the inch-and-half amphibian has swallowed a golf ball. When fully engorged with air, the pouch looks about the same size as the frog.
Once primed, the frog issues a guttural creaking aria often likened to the sound made by running a finger down the teeth of a comb. Remember that metaphor and you’ll never mistake the chorus frog’s song.
Air temperature influences the speed of the frog’s song. On a warm evening, its notes zip along speedily. In cooler weather, the cadence slows significantly. If the thermometer dips into the 40s, the song barely sputters along, and individual notes can easily be discerned.
Successful songsters attract females, and the amorous couple locks together in an embrace known as amplexus. The freshly fertilized female then deposits gelatinous egg clusters on aquatic vegetation; each cluster contains as many as 300 eggs.
A week or so later, tiny tadpoles burst from the eggs. About two to three months after hatching, the tadpoles metamorphose into frogs and leave the water.
Except during the spring breeding frenzy, Western chorus frogs typically live on land and are hard to find.
April is the peak month to take in the spectacle of frog mating orgies.
In addition to the chorus frogs and spring peepers, several other species can easily be found. They include American bullfrog, green frog, and Northern leopard frog. American toads are often part of the scene.
All of these amphibians are common in most of the state.
Franklin County Metro Parks support many fine amphibian habitats.
A “Secret Swamp” hike will be held on April 5 at Slate Run Metro Park, and a “Frog Frenzy” program will take place on April 19 at Prairie Oaks Metro Park. Both should produce plenty of frogs.
For more information, call 614-891-0700 or visit www.metroparks.net.
Naturalist Jim McCormac writes a column for The Dispatch on the first and third Sundays of the month. He also writes about nature at www.jimmccormac.blogspot.com.