Alaska Herpetological Society
Wood Frog (Lithobates sylvaticus)
Adults: 3.1-8.1cm (1.25-3.25 in) from snout to vent. Have dark “eye mask” that is flanked by a white or cream jaw stripe. Smooth skin. Some individuals have light stripe along spine. Underside is white or cream. They have dorsolateral ridges – two raised lines running down their back. The thumb base of males is dark and enlarged.
Eggs: Laid in 6.2-15cm (2.5-6 in) firm clusters, 100-3000 eggs per cluster (780 average), in shallow ponds, lakes or slow moving streams, near surface either floating freely or attached to vegetation, many clusters often located in close proximity.
Tadpoles: Tadpoles are 5 cm (2 in) long; uniformly dark underside, high dorsal fin, few markings on fins, dark body, dusky color with green sheen, underside cream color with hints of pink.
FACTS
1. Wood Frogs can be found far from water, in open forest, grassland, tundra and muskeg!
2. The Wood Frog is most easily recognized by its “robber mask.” This black band stretched past both eyes to the eardrums.
3. They are the most widespread of Alaska Amphibians and are even expected to occur on the North Slope, north of the Brooks Range!
4. They turn from eggs to tadpoles to adults rapidly and freeze almost solid in the winter allowing them to survive at high latitudes!
5. They produce a natural anti-freeze to keep the inside of their cells from freezing in the winter!
6. Their voice is a “rapidly repeating ducklike staccato.” They are often confused for ducks!
Wood Frog Calling Video