The wood frog is a medium-sized, tan, pinkish-tan, or brown frog with a dark brown mask through the eye and ear. A thin ridge of skin is present along each side of the back. Sometimes there are small dark markings scattered on the back, and there are usually brown or dark brown lengthwise bars on the hind legs. There is a prominent white line along the upper lip. Call is a quick series of “waaaduck” sounds.
Similar species: Young green frogs (including their bronze frog subspecies) can have a similar color, but they lack the distinctive dark brown mask through each eye.
Length (snout to vent): 1½–2¾ inches.
Scattered locations in eastern, southeastern, and southwestern sections of the state with mature forest.
Habitat and Conservation
In Missouri, wood frogs live in cool, moist, forested ravines and shady, north-facing hillsides where small, fishless ponds are available for breeding. They overwinter on land beneath deep layers of leaves or under moist logs and protect themselves from freezing by producing glucose in their blood that acts like antifreeze. This generally northern species is called a “glacial relict” because past glaciations pushed it to the southern part of its range, where it endures in cool locations.
Eats a variety of insects and other invertebrates.
A Species of Conservation Concern in Missouri. For a time in the 1970s it was classified in our state as being in danger of extinction, but new populations were discovered. Still, the frog is considered vulnerable in Missouri.
Active between February and October, a secretive and solitary species that can be difficult to observe after its short breeding season. Breeds between early February and late March in small, fishless woodland ponds or pools. Males gather at the pools to call from sundown to midnight, their muted voices often overpowered by louder and higher-pitched spring peepers. After only 2 or 3 nights, all the eggs are laid and the wood frogs leave the area. Wood frogs can live to be 10 years old.
When the perfectly camouflaged wood frog is sitting quietly among dead oak and maple leaves, it is nearly invisible. When you happen to see one of these rare frogs on a woodsy outing, you have received a special gift.
This species helps to check the huge growth potential of various insect populations, while also serving as food for snakes, raccoons, mink, and skunks. The eggs and tadpoles are food for various aquatic predators.