A Frog in Your Ears: Big sounds from small frogs fill the spring air

story by Bernard Brown | photo by Nick KiriazisOne early sign that spring has arrived is the sound of Spring Peepers. To call these frogs “peepers” is a bit of an understatement. They have loud, projecting calls. When you finally track down one of the little guys (easiest with a friend to triangulate on the sound), it’s a surprise to find a frog no bigger than your thumbnail, beige with a darker X on its back. Get a hundred together and you can’t hear anything else.

For me, this is one of the defining joys of spring. I’ll be out in a marsh at night, and I’ll wade into the middle. The peepers will shut up for a moment, frightened by the Godzilla in their midst. Then one courageous frog calls, a challenge a few more can’t resist, and soon I’m enveloped in an overwhelming chorus of “peep” as complete aurally as the night is visually.

Of course, the frogs do not intend to serenade me; the singers are males calling for love and defending their turf. They might be tiny, but they’re tough. Along with the peeps, you can make out little trills, the sound male peepers make in direct response to another male getting too close.

Here in Philadelphia, peepers sing down at the Heinz National Wildlife Refuge near the airport, and at just about any other rural water in the area where they can find shallows with weeds or grass to hide in. They are so common now that it’s hard to imagine spring without them. Unfortunately, once-common frogs and toads are disappearing all over the world, most famously due to a species of infectious fungus, Batrachochytrium dendrobatidis (Bd).

Could this happen to the peepers? Tim Maret, a herpetologist in the Shippensburg University Biology Department, has found that four species of chorus frogs, close peeper relatives, have been mysteriously declining throughout Pennsylvania for the past 50 years. The cause doesn’t seem to be pesticides. It might be Bd, but no one knows for sure. The sustained peeper population only deepens the mystery, says Maret, as one would expect something that hurts chorus frogs to also hurt their peeper cousins. Other Pennsylvania frogs are also in inexplicable decline: cricket frogs, northern leopard frogs and spadefoot toads. “Turning the unknowns to knowns is really hard,” says Maret. The difficulty in studying this problem is exacerbated by the lack of funding available to fuel the work.

For me, this is both a call to action and a reminder to get out and appreciate even the common creatures while they’re still common. Frogs and toads will be singing their little hearts out into June, so now’s the time to start enjoying them. Check out the North American Amphibian Monitoring Project (NAAMP) website (pwrc.usgs.gov/naamp) to listen to the calls before you head out into the field. The NAAMP uses volunteers to monitor frog populations. You can help build the database that helps researchers know how well (or poorly) populations are doing.

Bernard Brown is an amateur field herper, bureaucrat and director of the PB&J Campaign (pbjcampaign.org), a movement focused on the benefits of eating lower on the food chain. Read about his forays into the natural world at phillyherping.blogspot.com.