Tiny Frogs Announce Warmer Days Ahead

If you live near a wetland, you’ve heard them most evenings for the past few weeks. It can be so loud, you close the windows lest they keep you from sleeping.  In spite of this, the sound is often a welcome one because it means that surely warmer days are ahead. It is hard to believe all that noise comes from Spring Peepers, the smallest of our Connecticut frogs, not much bigger than a dime. It is a mighty effort from so small a creature!

 Spring peepers were long considered a type of tree frog, but they have been re-classified by herpetologists (scientists who specialize in the study of reptiles and amphibians) as a member of the family known as Chorus Frogs. Unlike the larger Wood Frogs that breed exclusively in vernal pools, peepers can be found in a wide variety of wetland areas from vernal pools to wooded swamps to the grassy edges of ponds and swamps.

They do not lay their eggs in large clumps like the wood frogs that have already left the vernal pools and their tadpoles behind. Rather, peepers attach their eggs singly beneath leaves at the bottom of a suitable wetland. When the tadpoles hatch they are tiny and can elude fish or other predators by hiding beneath the leaves where they feed on algae.

If you have a flashlight handy, tiptoe down to the edge of the wetland at dusk to try to locate a singing peeper in the beam of your light. This will not be easy as the tiny frogs seem to “throw” their voices. Finding one takes patience and a bit of luck, but your effort will not be wasted if you persevere. The male peeper’s throat bulges with air as it calls out for potential mates. Should another male approach the singer, the frogs will square off and wrestle for the right to sing from a favored perch. The winner remains, while the loser skulks off to find another location from which to call.

It was only recently that scientists discovered that many small frogs do not hibernate, but rather crawl under the leaves and freeze solid like ice cubes when the temperature drops well below freezing. With the warmer rains of early spring, they literally thaw and make their way to the same wetlands used by their ancestors to lay their eggs. By mid summer, many of these wetlands pools and edges may have dried up, but by that time the tadpoles will have become tiny froglets, and left the security of the pools for life in the forest. Peepers, along with wood frogs and several other Connecticut amphibians, do not lay their eggs in ponds and other larger water bodies. A single large fish might eat hundreds of tiny tadpoles in a single night. Since fish cannot live in the temporary vernal pools, these small wetlands provide a safer environment for spring peepers, wood frogs and several species of salamander in early spring.

Although the tadpoles may be safe from predatory fish, they do face other dangers. Many wetlands in Connecticut have been lost to development.  Pollution is another concern. In part, because they inhabit both land and water at different stages of their lives, amphibians are often considered “indicator species” that tell us something about the health of our environment. Let us hope we continue to hear the sounds of the spring frogs for many years to come. 

Visit Roaring Brook Nature Center this spring to learn more about amphibians.  The center maintains several species of frogs native to the Farmington Valley area.