Autumn Calls of Spring Peepers

Many people associate the call of peepers, the smallest frog in Connecticut, with the arrival of spring. Recently, while hiking on a warm fall day, I heard the “peeping” of Spring Peepers (Pseudacris crucifer). It wasn’t the huge chorus you usually hear at vernal pools and shallow ponds in March and April. It was just a few individuals calling back and forth. Instead of at the water’s edge, the sounds were coming from under the leaf litter. Why call in the fall, when it is not the mating season? Are these a different species?

A Spring Peeper (Pseudacris crucifer) calling in the spring. This tiny, one-inch (2.54cm) frog has a huge voice. Look at the size of its throat pouch! Photo by Justin Meissen, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0&gt;, via Wikimedia Commons.

I also checked out a vernal pool where I know Wood Frogs (Rana sylvatica) call in spring. There was actually a small chorus of them “quacking” in the leaf litter near the water. What’s going on?

Wood Frogs (Rana sylvatica) burrow into leaf litter in the fall and can actually freeze part of their body through the winter. They then “thaw out” and emerge to breed in vernal pools in the early spring. Photo by Peter Paplanus from St. Louis, Missouri, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0&gt;, via Wikimedia Commons

Spring Peepers, and sometimes Wood Frogs, can actually be heard calling in the fall. The Spring Peeper’s autumn calls sound a bit harsher and more abbreviated, with less of the sleigh bell-like chorus that you hear in the spring. Lang Elliot, a biologist who has recorded many sounds in nature, captured the calls of fall peepers.

Both Spring Peepers and Wood Frogs are getting ready to go into a very deep sleep called torpor. Their bodily functions slow down and they go into a near-death-like state—part of their bodies actually freeze! Although the spaces between their cells can freeze, they prevent their cells from freezing by producing glucose, thereby keeping vital organs alive.

There are several hypotheses as to why these frogs are calling in autumn, but one has to do with environmental conditions. The shortness of the days, lower angle of the sun, increasing rainfall, and cooler temperatures are very similar to spring conditions when these frogs become active. Some may be responding to these environmental cues.

I asked frog biologist David Skelly, director of the Yale Peabody Museum of Natural History and Frank R. Oastler Professor of Ecology at Yale, about it. He said in autumn, the weather can be like the spring breeding period. “These environmental cues may prod them into calling, since they undergo physiological changes during late summer and fall that will enable them to breed as soon as they become active after a long period of dormancy.”

The name Spring Peeper is not a misnomer. Peepers are a sure sign of spring. But you may also hear them and their Wood Frog cousins in the autumn months as these tiny creatures get ready to launch themselves into the mating game.

Published by Jim Sirch

Jim Sirch is the author of Beyond Your Back Door, a weekly blog about nature in your neighborhood. He is also Education Coordinator for the Yale Peabody Museum, a UConn Master Gardener and board member of his local land trust. As a trained naturalist, he brings a deep understanding of geology, plants and wildlife and how they interact within a particular ecosystem. He holds a B.S in Forestry from West Virginia University, a B.S. from Miami University in Science Education; and an M.S. in Environmental Studies Administration from Antioch University. He is also the 2014 Sigmund Abeles Award recipient from the Connecticut Science Teachers and Supervisors Association for outstanding science teaching and professional development.

2 thoughts on “Autumn Calls of Spring Peepers

  1. Message for you in messenger. Might be interesting

    On Wed, Dec 9, 2020, 12:23 PM Beyond Your Back Door wrote:

    > Jim Sirch posted: ” Many people associate the call of peepers, the > smallest frog in Connecticut, with the arrival of spring. Recently, while > hiking on a warm fall day, I heard the “peeping” of Spring Peepers > (Pseudacris crucifer). It wasn’t the huge chorus you usually hear ” >

    Like

Leave a Reply to Jim Sirch Cancel reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: