Gray Treefrog: Hyla versicolor

Common name: Gray Treefrog
Scientific name: (Hyla versicolor)
Classification name: Treefrog

Description: The Gray Treefrog looks identical to Cope’s Gray Treefrog. The two speciesand can only be distinguished from each other by their calls. They have rough, green, brown or gray skin with large darker blotches on the back. Like many treefrogs, they have large toe-pads. The two species can be distinguished from other frogs by the dark-edged light spot under the eyes and by bright yellow-orange colouration under the thighs. Adults may reach 6 cm.

Call The Gray Treefrog call is a short flutey trill. The call of Cope’s Gray Treefrog is a faster, higher pitched trill. It is similar to that of the American Toad but is much shorter. It has more trill than that of a Wood Frog.

Confusing Species: Other treefrogs found in their range are the Spring Peeper, Boreal Chorus Frog, Western Chorus Frog and the Northern Cricket Frog. The Spring Peeper has a large, dark X on its back while the Chorus Frogs have three stripes down the back. The Northern Cricket Frog, limited only to Pelee Island in southern Ontario, has a dark triangle between the eyes and less distinct markings on the back than the other three species.

Distributions: In Canada, the Gray Treefrog occurs from southeastern Manitoba to New Brunswick. It overlaps with Cope’s Gray Treefrog in Manitoba and extreme western Ontario. It is also found in the eastern half of the United States as far south as northern Florida and Texas.

Habitat: These treefrogs may be found on trees and shrubs near permanent water. They prefer mature or second growth woodlands although they may also inhabit orchards. They are rarely seen outside the breeding season.

Reproduction: Breeding occurs in late spring and early summer. During the day they remain in trees around the breeding pond. In the evening, males call from trees and shrubs but enter the pond after finding a mate. Up to 2000 eggs are laid in small clusters of 10-40 attached to vegetation. Eggs hatch within five days and tadpoles metamorphose 40 – 60 days after hatching.

Natural History: The Gray Treefrog is a tetraploid form of Cope’s Gray Treefrog, which is to say that it is genetically the same but has four copies of each chromosome instead of the usual two copies. The Gray Treefrog is a true tree frog; it can be found at the top of even the tallest trees. Gray Treefrogs overwinter under leaf litter and snow cover and can survive being frozen solid. Gray Treefrogs are sometimes found on the walls outside a building where there is a light that attracts insects. Like some other treefrogs it is freeze tolerant.

Conservation Concerns: Neither species is believed to be declining. Gray Treefrogs may be increasing in New Brunswick.