Gray Treefrog (Dryophytes versicolor) or Cope's Gray Treefrog (Dryophytes chrysoscelis)
Order Anura, Family Hylidae (Treefrogs), Genus Dryophytes. These are typical hylids characterized by specialized toe pads for climbing and a cosmopolitan distribution.
Species
Gray Treefrog (Dryophytes versicolor) or Cope's Gray Treefrog (Dryophytes chrysoscelis)
Family
Order Anura, Family Hylidae (Treefrogs), Genus Dryophytes. These are typical hylids characterized by specialized toe pads for climbing and a cosmopolitan distribution.
Size
Adults typically measure between 1.25 to 2 inches (32-51 mm) in snout-to-vent length (SVL). Females are generally larger than males.
Conservation
IUCN status: Least Concern. Populations are generally stable across their range, although they are sensitive to local habitat loss and water pollution.
Description
An master of mimicry, this frog resembles a patch of lichen on a tree trunk. In the provided image, its green-grey mottled skin and large toe pads are perfectly adapted for a life spent above the forest floor.
Key Features
Warty skin, light square-ish spot under the eye, expanded toe pads, and bright yellow/orange inner thighs.
Physical Description
A robust, medium-sized treefrog with a rounded snout. It possesses large, sticky toe pads and a noticeable, though sometimes faintly colored, tympanum. The eyes are prominent with horizontal pupils.
Skin Texture & Coloration
The skin is distinctly granular or warty. Coloration is highly variable, ranging from lichen-grey to bright green or brown. A dark, star or lichen-shaped blotch is usually present on the back. The inner thighs feature hidden, bright yellow or orange wash (flash colors).
Distinguishing Features
Key markers include a light spot with a dark border directly beneath each eye, granular skin, and the bright yellow-orange coloration on the hidden surfaces of the hind legs.
Habitat
Arboreal; primarily found in deciduous forests, woodlots, and swamps. They frequently utilize man-made structures like birdhouses, PVC pipes (as seen in the image), and porch lights.
Geographic Range
Native to the eastern United States and southeastern Canada. The range extends from Manitoba and Maine south to northern Florida and west to central Texas.
Behavior
Nocturnal and highly arboreal. During the day, they remain well-camouflaged against tree bark or tucked into crevices. They use 'flash coloration' on their thighs to startle predators during escape.
Diet & Feeding
Insectivorous, feeding on a wide variety of ants, beetles, moths, flies, and spiders. They are sit-and-wait predators that take advantage of insects attracted to lights.
Reproduction
Breeding occurs in spring and early summer in fish-less permanent or ephemeral ponds. Males call from vegetation near the water. Amplexus is axillary, and eggs are laid in small floating clusters.
Vocalizations
Dryophytes versicolor has a slow, melodic trill. Dryophytes chrysoscelis has a faster, harsher, higher-pitched trill. The two species are identical in appearance and are best distinguished by their calls.
Life Cycle
Eggs hatch in 3-6 days. Tadpoles have distinctive reddish or orange-tinted tails and metamorphose in 6-8 weeks. Sexual maturity is typically reached in 2 years.
Conservation Status
IUCN status: Least Concern. Populations are generally stable across their range, although they are sensitive to local habitat loss and water pollution.
Toxicity & Defense
While not dangerously toxic to humans, skin secretions can be mildly irritating to mucous membranes (eyes/mouth). Their primary defense is cryptic coloration and flash colors on the legs.
Ecological Role
They function as significant predators of forest insects and serve as a food source for birds, snakes, and larger amphibians.
Similar Species
The Gray Treefrog (D. versicolor) and Cope's Gray Treefrog (D. chrysoscelis) are identical except for chromosome count and call. Green Treefrogs (D. cinereus) have smooth skin and a white lateral stripe.
Observation Tips
Look near porch lights at night or listen for trilling choruses after warm spring rains. During the day, check crevices or the insides of horizontal pipes.
Handling & Safety
Safe to handle briefly with wet hands, but avoid touching your eyes or mouth afterward until hands are washed. Skin secretions can cause stinging.
Seasonal Activity
Active from early spring through autumn. They undergo brumation (hibernation) under leaf litter or bark during freezing winter temperatures.
Cultural Significance
Often considered the 'sound of summer' in eastern North America due to their loud evening choruses. They are commonly encountered by homeowners near garden lights.
Interesting Facts
These frogs are freeze-tolerant; they can survive the winter by producing glycerol in their blood, which acts as an antifreeze, allowing up to 40% of their body water to freeze.