Description: As the scientific name implies, gray treefrogs are variable in color owing to their ability to camouflage themselves from gray to green or brown, depending on the substrate on which they are sitting. The degree of mottling varies. They can change from nearly black to nearly white. They change color at a slower rate than a chameleon. One aspect that is unique to this frog appearance is that its legs feature a dark bandish pattern which then contrast sharply with the black-marked bright yellow or orange under the sides of its legs and arms. Dead gray treefrogs and ones in unnatural surroundings are predominantly gray. The female does not call and has a white throat; however, the male does call and can show a black/gray/brown throat during the breeding season. The female is usually larger than the male. They are relatively small compared to other North American frog species, typically attaining no more than 1.5 to 2 inches. Their skin has a lumpy texture to it, giving them a warty appearance.
This species is virtually indistinguishable from Cope's gray treefrog, the only readily noticeable difference being that Cope's Gray treefrog has a shorter, faster call. However, the call rates of both gray treefrogs are temperature dependent and at lower temperatures Cope's gray treefrog can have a call rate approximating that of the gray treefrog. The difference in call can be heard, but it is best quantified by counting the number of pulses per second in their whistled trills. The gray treefrog has a pulse rate of 16 to 34 pulses per second while Cope's gray treefrog has a pulse rate of 34 to 60 pulses per second. Even though there is potential for overlap, because of the temperature dependence of the pulse frequency the two species are easily distinguished where they occur together. At a given temperature, the pulse frequency for the gray treefrog is approximately 1/2 that of Cope's gray treefrog.
The gray treefrog also has 48 chromosomes (4n), and is called the tetraploid gray treefrog in scientific literature. Cope's gray treefrog, or diploid gray treefrog, retained its 2n (24) original chromosome count. Hybridization between these species results in early mortality of many larvae, but some individuals survive to adulthood though they have reduced fertility.
Both of these similar species have bright-yellow patches on their hind legs, which distinguishes them from other treefrogs, such as the bird-voiced tree frog. The bright patches are normally only visible while the frog is jumping. Both species of gray treefrogs are slightly sexually dimorphic. Males have black or gray throats, while the throats of the females are lighter.
Tadpoles have rounded bodies (as opposed to the more elongated bodies of stream species) with high, wide tails that can be colored red if predators are in the system. Metamorphosis can occur as quickly as two months with optimal conditions. At metamorphosis, the new froglets will almost always turn green for a day or two before changing to the more common gray. Young frogs will also sometimes maintain a light green color and turn gray or darker green after reaching adulthood.
Habitat: The gray treefrog is most common in forested areas, as it is highly arboreal. Its calls are often heard in rural residential areas of the East Coast and the Midwest. It prefers to breed in semipermanent woodland ponds without fish, but it also lays eggs in swamps, vernal pools, man-made fountains and water gardens, and even in rainwater-filled swimming pool covers.
Gray treefrogs inhabit various kinds of wooded and forested habitats and may occur on the ground or more often in shrubs or trees. Inactive individuals may be in tree holes, under bark, in rotten logs, under leaves, and under tree roots.Breeding sites include shallow woodland ponds and marshes, puddles, ponds in forest clearings, swamps, bogs, and many other kinds of permanent or temporary, natural or human-created waters lacking a significant current.
Range: Range includes southeastern Canada from southern Manitoba to New Brunswick (Weller 2002), and southward through the northeastern and south-central United States to North Carolina, West Virginia, Ohio, Indiana, Kentucky, Illinois, Tennessee, eastern Texas, and southwestern Louisiana, and west to North Dakota, Minnesota, Iowa, eastern Kansas, and eastern Oklahoma
Diet: Adult gray tree frogs mainly prey upon different types of insects and their own larvae. Mites, spiders, plant lice, snails and slugs are common prey. They may also occasionally eat smaller frogs, including other tree frogs. They are nocturnal and hunt in the understory of wooded areas in trees and shrubs. Larvae eat suspended matter, organic debris, algae, and plant tissue.
Reproduction: Mating calls and chorusing are most frequent at night, but individuals often call during daytime in response to thunder or other loud noises. Males produce advertisement calls for females as well as aggressive calls to counter other males. Females are able to discriminate between these. Breeding occurs in spring or summer, beginning as early as March in the southern part of the range and usually in May in the north Females deposit clutches of up to about 2,000 eggs, distributed among several small clusters. Aquatic larvae hatch in a few days and metamorphose within 2 months.
Status: This species is classified as Least Concern. However, habitat preservation is still important. Dryophytes versicolor requires terrestrial habitat adjacent to breeding sites as well as the breeding wetlands, with a minimum suggested terrestrial habitat buffer of 200 feet surrounding the main breeding pond.
Disclaimer: ITIS taxonomy is based on the latest scientific consensus available, and is provided as a general reference source for interested parties. However, it is not a legal authority for statutory or regulatory purposes. While every effort has been made to provide the most reliable and up-to-date information available, ultimate legal requirements with respect to species are contained in provisions of treaties to which the United States is a party, wildlife statutes, regulations, and any applicable notices that have been published in the Federal Register. For further information on U.S. legal requirements with respect to protected taxa, please contact the U.S. Fish and Wildlife Service.
){kind=link}