The Spring Peeper (Pseudacris crucifer) is a harbinger of spring over many parts of the United States. It is found all over the eastern half of the United States. It's high "peep" calls echo throughout woodlands as the winter turns to spring. This individual was calling in Bayou Meto State Game Area in Arkansas on a cool, rainy, March night.
The call of the Spring Peeper is, as you might imagine, a loud "peep". Here is an individual calling from Burns Park in Little Rock, Arkansas.
Here is the spectrogram for the call. Notice all the harmonic bars above the main call note.
So the name Spring "Peeper" is a reference to its call, but the scientific name Pseudacris crucifer is a reference to the X shaped "cross" on the back of most specimens -
A loud chorus of Spring Peepers can be almost deafening. This chorus is also from Bayou Meto State Game Area in Arkansas.
Here is the spectrogram for that chorus. You can still see the individual calls and the harmonics.
When there are enough peepers calling, you lose the ability to discriminate individuals, like in this recording from the same area:
© Chris Harrison 2013