From Ohio History Central
The gray treefrog (Hyla versicolor) is a master of disguises. The largest treefrog in Ohio, the gray treefrog can be any shade of brown, green, gray or black, using its camouflage to blend into its surroundings. Instead of using its coloring, it can be identified by the unchanging, dark-edged light spot beneath its eye and the bright yellow on the inside of its thighs.
The gray treefrog is found in the northern two-thirds of Ohio.
Treefrogs are nocturnal and spend most of their time in a habitat of small trees and shrubs. Their toes have large, sticky pads that help them to cling to tree trunks and climb them quickly. They will jump from limb to limb to catch prey. It is common to hear their woodpecker-like call coming from trees and shrubs just before and after a rain. Treefrogs come down only at night and during breeding season, when large numbers of them go to nearby ponds.
Breeding begins not long after coming out of hibernation. Gray treefrogs are one of the last frogs to come out in the spring. Between April and August females will lay approximately 1,800 eggs in temporary or permanent ponds in swamps, forests, or fields. They have even been known to lay eggs in swimming pools. The eggs will hatch after just 3 - 5 days, and the tadpoles will metamorphose into young treefrogs in 45 - 65 days. The tadpoles have a good chance of reaching the frog stage because they produce a foul tasting substance that keeps predators away. Young treefrogs are a bright green color.
Adult treefrogs average 1.25 - 2 inches in body length. They may live 7 - 9 years feeding on a diet of moths, crickets, ants, grasshoppers, and beetles.
Like the Eastern wood frog, the gray treefrog will produce glucose, or sugar, and "freeze" itself for the winter.