Congratulations to Naturally Curious readers for their familiarity with Eastern Gray Treefrog (Hyla versicolor) toe pads! This is the easiest time of year to find these amphibians, mainly because of their habits. During the fall, winter and spring treefrogs are usually silent, unlike the summer, when males can be heard calling their melodic trill from bushes and trees near bodies of water after the evening air temperature rises above 59°F. Because they are nocturnal, well camouflaged, and hibernate in the winter, you don’t often come across one except for the warmer months when males are calling. The colors of an Eastern Gray Treefrog (brown, green and pearl-gray) vary with the colors of its background and environmental factors such as season and humidity, but shades of gray are most common. Their green color is more prominent during the breeding season and in young frogs.
When hunting insects, or when disturbed, treefrogs can leap great distances and, thanks to advanced toe pads, when they land they can cling to practically any surface, including vertical branches and leaves that are wet. A very low angle between the toe pads and substrate as well as mucous glands located in channels between the hexagonal pattern on a treefrog’s toe pads have inspired the design for treads on car tires.
You can listen to an Eastern Gray Treefrog’s call by going to http://langelliott.com/calls-of-frogs-and-toads-of-the-northeast/ (Sound recording © Lang Elliott – langelliott.com)