By Susan Thurn,
Cable Natural History Museum
Little Frog with a Big Voice
“Peep, peep, peep,” is the incessant voice of a little frog with a very big voice. It is a sound I look forward to every spring. The spring peeper is light brown in color with a darker cross that forms an X on its back. With a length of one to one and half inches long, and a weight that is only that of about a penny, they are amazing amphibians. The peeping sound they make in the spring is worth a trip outdoors on any warmer night.
Spring Peepers are first heard in March or April, once the ground is thawed enough by early spring rains, or as snowmelt fills lowlands, ponds and wetlands. These vernal, spring-time ponds and other wetlands are the host to these peepers that spend other parts of the year in forests near their permanent or semi-permanent wetlands. Woodland ponds that are filled with shrubs, branches and twigs above and in the water are preferred areas as well, where they can grasp on branches or cling to the edges.
It is only the male peepers that have a vocal sac near its throat that expands and deflates like a balloon to create the distinct peeping sound. They use the sound to attract the ladies. Male spring peepers call out from their perches in the brush or on grass edges, above the water to attract female attention. When we come close, they hop in for safety.
Dusk and early morning hours are preferred times for spring peeping. Their calls can be heard from up to two and one half miles away depending on the amount of peepers in the pond. One small pond typically has hundreds of individuals all in one place, making a very loud sound!
When eggs are laid, one spring peeper female can lay up to 1,000 eggs which are hidden at the water’s base near vegetation. For the next 8 weeks the young feed on algae or other organisms in the water as they go through the larval tadpole stage.
Spring peepers are active nocturnally, where they feed on invertebrates like worms, spiders, and insects such as flies, beetles, or ants. Although they are considered a treefrog and have toe pads to allow them to grasp on to trees, they usually do not climb higher than our knees.
Because they are cold-blooded, spring peepers go through a form of hibernation. Parts of their bodies will freeze and have ice crystals in them. However, spring peepers can produce glucose in their livers, a sugar that acts like anti-freeze. This glucose is pumped to their heart and lungs so they can survive even sub-zero temperatures.
When is the best time for one of those evening peeper strolls? Spring peepers will call down to a temperature of about 36 degrees Fahrenheit, so almost any night is a good night to enjoy these great amphibians in our back yards!
For over 42 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The new exhibit, The Joy of Birds, Feathers in Focus opens May 3rd, 2011. Find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Also discover us on the web at www.cablemuseum.org, on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com/ to learn more about our exhibits and programs.