The northern spring peeper’s vocal sac is almost the same size as its entire body. (Douglas Mills/Flickr)
The northern spring peeper is a tiny, brownish tree frog with a distinctive X-shaped cross on the back. It lives in marshy woods and near ponds and swamps throughout the Chesapeake Bay watershed. Its “peeping” call is one of the first signs of spring in the region.
Varies in color from grayish brown to olive
Dark X-shaped cross on the back
Large toe pads on each webbed foot
Dark bands on the legs
Dark bar between the eyes
Vocal sac under the chin that puffs out when making a call
Grows 3/4 to 1 1/4 inches long
Lives in marshy woods, temporary wetlands, and non-wooded lowlands near ponds and swamps
Tends not to go more than 3 feet above the ground when climbing trees
Common throughout the Chesapeake Bay watershed
Feeds on small insects such as ants, beetles and flies, as well as spiders
Preyed upon by many predators, including owls and other birds, snakes, salamanders and large spiders
Males emit a single clear note or “peep” once every second during breeding season
Calling may be louder on humid evenings or after a warm spring rain, when males congregate
The northern spring peeper’s distinctive call is one of the first signs of spring in March
Males also make a lower-pitched trilling whistle when another male moves too close to its calling site
Reproduction and Life Cycle:
Breeds from March until June in freshwater ponds without fish
The male’s call is extremely important during breeding season. Females choose their mate based on the quality of the call. The faster and louder he sings, the more likely he us to find a mate.
Females lay hundreds of eggs in the water. The clumps of eggs attach to twigs and aquatic vegetation.
Once breeding season is over, peepers move into woodlands and shrubby areas
Eggs hatch within 6-12 days, depending on temperature
Tadpoles (young peepers) are able to breathe with gills and swim using a tail. Their tail actually makes tadpoles larger than adult peepers. As they mature, tadpoles lose their tail and develop lungs for breathing.
Within eight weeks, tadpoles are fully transformed into young frogs and leave the pond
Peepers grow to their adult size by the end of the summer and reach maturity within one year
The smallest and most well-known treefrog in the Chesapeake Bay region
Among the first animals to call and breed in spring
Northern spring peepers are excellent climbers due to their large toe pads. However, they prefer to remain close to the ground.
The X on the northern spring peeper’s back isn’t always a perfect form, but it is present in some way. This identifying mark is where the peeper gets part of its scientific name, crucifer, from the word “crucifix.”
The northern spring peeper’s vocal sac is almost the same size as its entire body
Northern spring peepers produce glucose and “freeze” themselves to hibernate during winter. They return to normal when temperatures warm up again.
Sources and Additional Information:
Chesapeake Bay: Nature of the Estuary, A Field Guide by Christopher P. White