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Canadian Herpetological Society Société d'Herpétologie du Canada |
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Spring Peeper
Pseudacris crucifer
Family: Hylidae
COSEWIC status:- Not Assessed
- No Status
- Least Concern
Description
The Spring Peeper is a small frog that is generally under 4 cm in body length. Individuals range in colour from tan, grey, rusty brown or dark brown. There is a conspicuous dark X-shaped marking on the back, a triangular or V-shaped marking on the head between the eyes, cross bands on the hind legs, and a dark stripe that extends from the snout, through the eye and part way down the side to the groin. The belly is white or cream-coloured and the inner thighs are light to dark yellow. The skin is granular in texture and individuals have small but obvious toe pads and lack webbing between the toes. Larvae (tadpoles) have long tails with a large fin and lack front legs (newly hatched tadpoles are legless). In Canada, the bodies and tail musculature of young tadpoles are tan/brown with darker mottling and the tail fin is clear. As the tadpoles age, they gain golden or brassy flecking on the body and large dark blotches along the edges of the tail fins. The larvae typically grow to 3–4 cm in total length before metamorphosis. The call is a single high-pitched “peep” which is repeated. There is also an ascending trill which is used in male-male interactions, and this trill is sometimes confused with a chorus frog call.
Similar Species
The Spring Peeper may be confused with the Western Chorus Frog and Boreal Chorus Frog. However, the Spring Peeper has a distinctive X-shaped blotch on the back, whereas the chorus frogs have three stripes (sometimes broken into blotches).
Distribution
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The Spring Peeper is widespread in eastern Canada, ranging from northwestern Manitoba to Prince Edward Island and Nova Scotia. With the exception of southern Florida, Spring Peepers are found throughout the eastern half of the United States as far west as Minnesota in the north and eastern Texas in the south.
Habitat
This species breeds in wide variety of shallow, open-canopy aquatic habitats, such as vernal pools, beaver ponds, marshes, bogs, swamps, ponds and around the edges of lakes. Temporary water bodies that are fish-free and that hold water for more than 4 months during the spring and summer are most likely to be used for breeding. Outside of the breeding season, individuals inhabit forested areas, usually with a few hundred meters of the breeding sites. Whenever possible, individuals hibernate below the frost line in mammal burrows, ant mounts, tree root cavities and other underground features. Individuals may also hibernate under logs or buried in the leaf litter.
Biology
In Canada, Spring Peepers hibernate during the winter and are typically active from late March or April until late September or October, depending on latitude. Males call to attract females during the breeding season, which occurs in the early spring from April to early June, depending on latitude. Individuals may also call in the late summer and fall but little-to-no breeding occurs at this time. During breeding, the male grasps the female (amplexus) and fertilization occurs externally in aquatic habitats as the female lays eggs. The female lays between 200–1500 eggs, singly or in small clusters, which are attached to submerged vegetation near the bottom of the pool. The eggs are dark brown to black on top and white to cream-coloured underneath and are surrounded by two clear jelly envelopes. The eggs develop rapidly and hatch in 1–3 weeks, depending on water temperature. The tadpoles transform into frogs after 2–3 months, depending on latitude, and most individuals reach sexual maturity in the first or second year after metamorphosis. Spring Peepers typically only live for 3–4 years. Like several other species of frogs that extend into northern Canada, Spring Peepers are able to survive sub-freezing temperatures during hibernation by increasing the levels of glucose in their blood, which acts as a “cryoprotectant” and prevents water from freezing inside the cells. Individuals forage for a wide variety of insects, as well as other invertebrates such as spiders, mites, centipedes, snails and slugs.
Threats
Spring Peepers occur throughout large expanses of Canada that are relatively undeveloped, and threats to this species are minimal throughout most of its range. Habitat destruction, particularly the loss of breeding ponds, can result in population declines or local extirpation. Pollution, such as herbicides and road salt, can be detrimental to frog populations by causing direct mortality as well as developmental deformities. Road mortality can be a significant threat when roads bisect the species’ habitat. Pathogens such as chytrid fungus and Ranavirus can cause mass mortality of frog populations. Climate change may also pose future threats to Canada’s frog populations.