by Barbara Walvoord
There’s no more wonderful sound of spring than the spring peepers trilling their chorus in the evening. We hear them all around us at Lathrop now, but you’ll rarely see them because they are well camouflaged and can shade their grey and brown colors to match their background.
All that trilling emanates from little amphibians about the size of a thumbnail. They climb into shrubs or trees that hang over water–you’ll see why in a minute. They make that sound through an air sac that inflates to nearly half the size of their own bodies. It looks like a junior high school kid with bubble gum.
In this past harsh winter, you might have complained, “I’m freezing,” but stop whining. Storing sugars in their cells allows peepers’ bodies to literally freeze during their winter hibernation in the mud near a pond. No wonder they sing with such joy when the weather warms.
They’re out and about now, voraciously hunting down beetles, ants, flies, and spiders–and also trying to make more peepers.
Only the males are producing this mating call. The females are trying to decide, amid all that racket, who has the best song, the loudest song, or something–I don’t know how they decide.
It’s dangerous to make that much racket, and dangerous to be that small. So during the day, when more predators like snakes and turtles are about, these little creatures hide in the debris on the forest floor or in grassy fields.
But they have to be near water, because that’s where they mate, and that’s where the mom lays her eggs. Especially, they need fishless water, because fish will eat their eggs. A body of water is fishless when it dries up during part of the year. So our ponds, wetlands, and vernal pools at Lathrop are ideal. Like other amphibians, however, they are very sensitive to pesticides and herbicides. In one study, DDT was found in peeper bodies 26 years after it had last been used near their pond (http://www.uri.edu/cels/nrs/paton/LH_spring_peeper.html).
The males may blow hard all night, but mom also works hard. In the spring she lays between 200 and 1200 eggs, each one singly attached to an underwater plant. That’s it. She’s off to the nearby woods and fields, leaving her babies to fend for themselves.
Her eggs hatch in 2 days to 2 weeks, depending on temperature. The little tadpoles breathe with gills and swim with their tails. As they mature, gills are replaced by lungs and tails fall off. After about 8 weeks they leave the pond–perhaps just as it is drying up for the summer.
How clever of them to straddle grey and brown, day and night, water and land, freeze and thaw, gills and lungs, to outwit their predators. Spring peeper is too puny a term, I think, for these raucous, voracious, hard-working, freeze-resistant, resilient little carnivores. Lathrop provides their straddling environment–fishless vernal pools, ponds, and wetlands with nearby woods and fields full of the native plants that support the bugs they eat. Our reduction of herbicides and pesticides will be especially important to their wellbeing.