Something Wild: Why are Spring Peepers so loud?

Tiny frogs herald springtime in northern wetlands

Dave Anderson, Chris Martin | March 29, 2019

A tiny spring peeper: easy to hear, harder to see

It’s an unmistakable sound.

One that elicits memories, sights and scents of events long ago. It recalls the joy of youth, the possibility of a spring evening. But it can also incite insomnia and the blind rage that accompanies it.

Psuedacris crucifer is better known as the spring peeper, and for most people it is a more welcome harbinger. These remarkable frogs spend the winter under leaf litter in a state if suspended animation. Once overnight temperatures are regularly in the forties, they start thawing out and begin singing. So that ringing chorus is a signal that we’re finally shedding winter’s icy grip. We dare to hope that we’ve seen our last nor’easter of the season; and that warmer and greener days are close at hand.

That hope manifests around the state on Facebook and Twitter (#peepers) – though not Instagram because photos of this tiny frog are elusive. It’s fun to watch the state gradually thaw from south to north, vicariously through social media. Posts always pop up first in places like Keene and Pelham; within a day or two Hancock and Hillsboro join in; the following week Franconia and Milan add their voice to the chorus. Before long, as streams begin flowing again and water returns to wetlands, the hills of New Hampshire sing with social media posts and peepers!

It’s no wonder we hear them so clearly. They’re loud, for a couple reasons. One study found that when you are within 50 centimeters of a single male peeper, it’s as loud as a motorcycle is from 25-feet away – about 90 decibels. Impressive when you consider your average male is only about an inch and a half long. However, from a distance, the chorus of peepers is little more quiet, only about 65 decibels, but still about as loud as your average bar room conversation. So cut your insomniac neighbor some slack when he starts screaming out the window at these amphibians.

Additionally, peepers tend to intuitively find places that amplify their call; in cracks or crevices, on tall vegetation, or near reflective surfaces like sheets of water. And the amplification can create a ventriloquy effect, casting the chirp all over your backyard making it difficult to hone in on where the frog actually is!

Another reason the peepers seem so loud is also psychosomatic. Since that blanket of snow descended late last fall, the outside has been nearly silent, and we’ve gotten used to that. So, by comparison those peepers are piercing. It’s like having earplugs in for five months then taking them out just as your alarm clock goes off.

So what are they doing? Precisely what you think they are. The peeper’s chirp is a mating call, males advertising for females. All that sound and fury wraps up pretty quickly, eggs are laid, fertilized and wrapped around plant stems, and mating season is over in just a few weeks. Peepers then make their way back into the forest for the rest of the spring and summer, in search of those cooler temperatures and damp places that they prefer