Wisconsin Sea Grant Frogs: Field Guide
Spring Peeper Frog
(Pseudacris crucifer crucifer)
Call: A high-pitched, rising "peep!" given
about one per second; a male peeper may also give a lower-pitched trilled
whistle, usually when another male has moved too close to its calling
Size: 2-3.7 cm in length (0.8-1.5 inches)
Brown, tan or gray with dark slanting stripes on the back that usually
form an X-shaped mark; the belly is white, yellowish or cream colored;
this frog has some color-changing ability and can darken or lighten, depending
on its mood or the surroundings
Found in temporary and permanent ponds, marshes, floodings, and ditches;
after the breeding season they move into woodlands, old fields or shrubby
areas; common throughout the Great Lakes region, except in the far north
along northeastern Lake Superior.
Striped Chorus Frogs have a light upper lip line and lengthwise stripes,
instead of the X-like marking, on the back; Cricket Frogs are wartier
and have a dark stripe on the inner thigh.
Breeding: Late March into May
FACT: Spring Peepers have large "vocal sacs" under their
chins. They pump these sacs full of air until they look like a full balloon,
then let out a mighty "peep" while discharging the air. The
easiest way to see calling Peepers is to look for their shiny vocal sacs,
which look like 25-cent pieces, inflating and deflating as they call.
The loud, peeping chorus of Spring Peepers means winter is finally coming
to an end. These little frogs are among the very first to call and breed
in the spring, often starting while there is still snow on the ground
and ice on the lakes.
Did you know?
A spring pond full of peeping Peepers can sound like sleigh
bells jingling -- only louder. Sometimes peepers make their calls while
sitting under clumps of grass or in cracks or crevices in the earth. This
position allows them to amplify the call, and also can create an effective
ventriloquism: the frog sound seems to come from somewhere other than
where the frog actually is!
copyright 2001 University
of Wisconsin Sea Grant Institute