North Carolina Wildlife Resources Commission

Wood Frog

Scientific Name: Rana sylvatica
Classification: Nongame species
Abundance: Western NC with exception of population in Hyde, Tyrrell counties (blue)


Photo by Jonathan Mays

 

 

 

 

 

 

 

 

     

The wood frog is a medium-size frog (1.5 to 2.75 inches) that may be brown, gray, reddish or pinkish, with a distinct dark brown mask and prominent ridges running along each side. Females are larger and sometimes more colorful than males. They are fast and agile leapers and are found throughout much of the mountains and western Piedmont in North Carolina. A disjunct population, which may be an ice age relict, is found in Hyde and Tyrrell counties in eastern North Carolina. As adults, wood frogs are found almost exclusively on land, living in moist woodlands. In parts of the mountains, they may be seen on roads on rainy nights most of the year.
Wood frogs breed in winter, most often in February. They usually breed in temporary woodland pools. They are explosive breeders, gathering in large numbers for breeding frenzies that may last only a few days. The large, globular egg masses are usually attached to sticks or aquatic vegetation. Often, many egg masses are deposited together in a small area; this may help protect them from freezing. The eyes of wood frog tadpoles are situated farther towad the sides of their bodies that most of North Carolina's "true frog" tadpoles. Tadpoles transform in about 8 weeks.
Wood frogs are extremely cold-tolerant and have been known to survive freezing of their body tissues.

The wood frog is classified as a nongame species with no open season. It is unlawful for any person to take, or have in possession, any nongame mammal or bird unless that person has a collection license or is collecting fewer than 5 reptiles or fewer than 25 amphibians that are not endangered, threatened, or special concerned species.

There are no reported problems with this species. 

Frogs and toads can be monitored fairly easily in a variety of ways. One way is through frog call monitoring. The North Carolina Calling Amphibian Survey Program attempts to do just that by corralling data collected by volunteers across the state that monitors specific frog call routes. Each species of frog and toad has a unique call that is distinguishable from others.  Some are more difficult for humans to separate than others, but the frogs know who’s who!  Learn your frog calls, and you too can distinguish who’s calling in the ponds.  Another way to monitor frogs and toads is by looking for egg masses deposited in wetlands and/or by looking for tadpoles in those same wetlands. Different frogs breed at different times of the year, so when to look for eggs is dependent on the species of interest. Eggs typically hatch within a couple weeks of being deposited, so there is a fairly short window for detection. Frog eggs can sometimes be identified to family, but are somewhat tricky to identify to species level.  Tadpole identification can be similarly tricky, so learning and listening to frog calls is definitely the easiest method for determining what frogs and toads are using a wetland. Tadpoles are a little easier to monitor, as most species have tadpoles present in wetlands for longer periods of time. This is, again, variable by species.  Most species have tadpole stages that last at least several months, but the range in timing for different species is everything from a couple of weeks to several years.  The smaller frog and toad species tend to have shorter tadpole cycles, while the larger frogs and toads tend to have longer times to metamorphosis.