Peeper Season, Earth Day, and Scouting With Your Ears for a Healthy Watershed

It’s that lovely time of year when an explosion of song rings from every valley and echoes from every hillside. This is the song of spring peepers, tiny frogs (actually, hundreds or thousands of tiny frogs). Their song carries a mile or more. It might even alert you to small wetlands or vernal ponds you didn’t know were out there. (Vernal ponds are low spots in woods or meadows that dry up as the season progresses.)

Driving along a river or stream? Roll down the windows and you’ll hear the peepers’ serenade. Stepping outside for a breath of fresh spring air? You’ll hear it the moment you open the door.

a spring peeper is perched on someone's thumb highlighting how small it is
We said it was tiny. Zoom in and you’ll see the “X” on its back, and you’ll know it’s a peeper you’ve found. Photo: Fyn Kynd flickr

It can be your own private celebration of Earth Day.

That is, if you have the good fortune to live where wetlands and ponds support these tiny frogs. Even if you don’t, peepers have a story for you.

Basics first: think of spring peepers as watershed indicator species, for they thrive only in healthy ecosystems. Peepers are amphibians — tiny frogs about an inch long, maybe more. As young-uns, they’re tadpoles (or pollywogs as you prefer) and live in the water, slowly growing legs and absorbing their tails even as lungs replace their gills.

a male spring peeper is shown with its throat fully inflated
Male peepers inflate a balloon-like sac to make their music — and attract females. Females often choose the males with the deepest songs. Photo: Andrew Hoffman flickr

After a month or so, peepers move to dry land. Their sticky toe pads help them cling to shrubs, tall grasses, and even trees, though mostly they seek the shelter of a damp wooded understory. Fall and winter will come — but no matter; a natural antifreeze in their bodies helps them survive the winter. Come spring, peepers return to water to lay their eggs. And thus their song — rapturous at a distance; raucous, even deafening, close by. And that song? It’s all about mating. Egg-laying. Time for another generation of young-uns.

Like other amphibians — toads, salamanders, and such — the peepers’ skin is moist and permeable, since they live both in water and on land. They absorb oxygen through their skin as well as their lungs. So back to the ecosystem part. Peepers absorb other things too — things that might contaminate wetlands and kill the critters in them. Salt runoff from nearby roads. Pesticides from nearby lawns or farm fields. Besides,  polluted watersheds tend to be oxygen-starved.

Look around you. Do you live or work in a peeper-friendly neighborhood? Are the lawns, fields and gardens cared for with core IPM practices? A too-perfect lawn, for instance, hints that its owner might be overfond of pesticides and fertilizers.

New York City has worked hard to protect its vulnerable wetlands, like this one on Staten Island.

An online search could help you learn where to go to find peepers in spring. If you live in a city, you can take the train to the nearest places where frogs are likely to thrive. Places where your ears will be your tool for scouting (a key IPM term) for the peepers’ presence or absence.

So — big picture. Recall that peepers and other amphibians are watershed indicator species. What is it with wetlands; why do they matter?

Wetlands are like natural sponges that trap, store, and slowly release surface and groundwater, rain, snowmelt, and more. They put the brakes on coursing floods, distributing them over the floodplain. This combined storage and braking action helps lower floods while slowing erosion.

Wetlands within and downstream of towns and cities are especially valuable. When storms hammer pavement and buildings, all that runoff has got to run somewhere. Often as not, it ends up in the nearest river. If that river is bordered by wetlands, they’ll give nature a hand, helping control floods and waterlogged crops — and without the expense of levees or dredging. Similarly, wetlands help alleviate pollution near cities and towns — and much more cheaply than a water treatment plant can.

You can find vernal ponds in forests or fields. “Vernal” means “relating to spring.” Because these ponds dry up in summer, fish can’t survive — making one less predator for peeper tadpoles to contend with. Photo: Judy Schmidt flickr

But if the wetlands have been filled in, drained, or contaminated beyond their ability to process pollutants — then what? I think you know. And as we speak: a mystery pest is decimating massive stands of the roseau cane, a wetland grass vital to the health of Louisiana’s precarious coast. Could this mystery pest ever get here? No idea. But if you’re curious, here’s the story.