Spring peeper, Pseudacris crucifer, from Anoka County, MN
No status assigned in Minnesota.
The spring peeper is one of the smallest frog species in Minnesota. They are from less than one inch to 1 1/2 inches in body length. Ground color varies from gray to different shades of brown. Some specimens appear rust red or orange. Like many other frogs, shade of color is affected by temperature. There is a distinctive dark X on the back. There also may be random dark dashes on the body. There may be a dark stripe that starts at the snout and continues through the nostril and eye to the posterior edge of the tympanum, and a bar on the head connecting the eyes. The legs have bars on them. The plain belly is a slightly lighter shade of the ground color. Spring peepers have tiny toe pads; much smaller than those of the larger treefrogs.
There are no subspecies of Pseudacris crucifer recognized.
Spring peepers are found throughout the northern third of Minnesota and in the eastern half of the remainder of the state.
Spring peepers are a woodland-woodland edge species. They are not found in open areas or large bodies of water. Smaller wetlands, even some that may dry up later in summer are used for breeding by spring peepers.
Spring peepers are heard earlier in spring not long after ice melts on the wetlands. Their normal breeding season lasts from April through May. They make a distinctive ascending "peep peep peep" much like that of a baby chick's peep. A large chorus can be ear splitting up close! Eggs are usually laid in small clusters. The small tadpoles transform in about three months. Adult peepers do not move far away from the breeding site during summer in the more open areas. Peepers from the deep woods will move some distance especially during rainy weather or if there are many small pools of water in the forest. They overwinter on land. They allow the water in their bodies to "freeze" except converted glucose flowing through the organs to keep ice crystals from forming just as in the gray treefrogs.
Spring peepers feed on small invertebrates. They do not climb high into trees but hunt in low vegetation. Specimens in deep damp forests are active hunters both day and night, whereas those found in woodland edges restrict most hunting and activity to night.