Boreal Chorus Frog (Pseudacris maculata)
Order Anura, Family Hylidae, Genus Pseudacris, Species P. maculata. Member of the tree frog family, but largely terrestrial/fossorial.
Species
Boreal Chorus Frog (Pseudacris maculata)
Family
Order Anura, Family Hylidae, Genus Pseudacris, Species P. maculata. Member of the tree frog family, but largely terrestrial/fossorial.
Size
Adult SVL typically 1.9 to 3.8 cm (0.75-1.5 inches). Females are generally slightly larger than males. Very light weight, often less than 2-5 grams.
Conservation
IUCN Status: Least Concern. Generally stable, though local populations face threats from habitat loss, wetland drainage, and pesticides. Some northern populations are sensitive to chytrid fungus.
Description
A diminutive herald of spring, the Boreal Chorus Frog is often heard long before it is seen. Its small size allows it to blend into the grass and mud of vernal pools, where it produces a surprisingly loud, metallic rasp that signals the end of winter. Its striped appearance provides excellent camouflage among dead grasses and leaf litter.
Key Features
Three dark dorsal stripes, dark eye mask, small size (under 1.5 inches), and lack of large toe pads or prominent skin folds.
Physical Description
Small, slender-bodied frog with a pointed snout and slightly rounded head. Eyes are medium-sized with horizontal pupils. Limbs are short relative to length; toe pads are present but very small and inconspicuous compared to arboreal tree frogs.
Skin Texture & Coloration
Skin is smooth to slightly granular. Background color ranges from tan or grey to olive-green. Features three prominent dark brown longitudinal stripes down the back (sometimes broken into spots) and a dark mask-like stripe extending from the snout through the eye to the groin.
Distinguishing Features
Three dark dorsal stripes; dark eye stripe continuing to the leg; small toe pads; white line along the upper lip. Lacks the enlarged toe pads of Hyla species and involves no distinct dorsolateral folds found in Ranids.
Habitat
Open wetlands, damp meadows, river valleys, and forests. Prefer shallow, often ephemeral water bodies like vernal pools, flooded fields, and roadside ditches for breeding. Found up to 3,700m elevation.
Geographic Range
Broadly distributed across central North America, from the Canadian Northwest Territories down through the Great Plains to New Mexico and east to the Great Lakes region.
Behavior
Primarily nocturnal but active during the day in early spring. Terrestrial and secretive, often hiding under logs, rocks, or leaf litter. They are weak climbers despite being in the tree frog family.
Diet & Feeding
Insectivorous. Consumes a variety of small invertebrates including ants, beetles, spiders, flies, and mites. Employs an active foraging or sit-and-wait strategy.
Reproduction
Explosive breeders in early spring. Triggered by snowmelt and early rains. Males callจาก shallow vegetation. Amplexus is axillary. Eggs are laid in small clusters (20-100) attached to submerged vegetation.
Vocalizations
Highly distinctive 'creaking' call resembling the sound of a fingernail running over the teeth of a plastic comb. It is a short, rising rasp that can be heard from long distances during choruses.
Life Cycle
Eggs hatch in 3-14 days. Tadpoles are small and dark, metamorphosing in 40-90 days depending on temperature and water availability. Sexual maturity is usually reached within 1 year.
Conservation Status
IUCN Status: Least Concern. Generally stable, though local populations face threats from habitat loss, wetland drainage, and pesticides. Some northern populations are sensitive to chytrid fungus.
Toxicity & Defense
Not toxic to humans. Defenses include excellent crypsis (camouflage), hiding in dense vegetation, and a frantic hopping flight response when startled.
Ecological Role
Important control agent for small insect populations and a critical food source for snakes, birds, and larger amphibians during the early spring when other prey is scarce.
Similar Species
Western Chorus Frog (P. triseriata) is nearly identical but generally smaller with shorter legs; Spring Peeper (P. crucifer) has an 'X' marking on the back rather than stripes.
Observation Tips
Listen for 'comb-like' rasps near roadside ditches or flooded fields on the first warm rainy nights of spring. Use a flashlight to search low in the grass at the water's edge; they will stop calling if they feel vibrations from footsteps.
Handling & Safety
Safe to handle but skin is sensitive. Always have wet hands and avoid using lotions or insect repellent, as their skin is highly permeable. Release immediately in the same spot where found.
Seasonal Activity
One of the earliest frogs to emerge in spring (as early as March). Active throughout the summer in moist areas; hibernates underground or beneath leaf litter during the winter.
Cultural Significance
Recognized across the Midwest and Canada as a primary symbol of the changing seasons. Often featured in local nature lore as the 'first voice' of the spring thaw.
Interesting Facts
Like some other northern frogs, they can survive sub-freezing temperatures by producing glucose and urea in their blood, which acts as a biological antifreeze to prevent ice from damaging cells.