Northern Green Frog
Lithobates clamitans melanota

The northern green frog is a very common and abundant species whose range extends throughout most of eastern North America, excluding the gulf coast.  It inhabits a diversity of aquatic environments in Maryland, from freshwater marshes to shallow ponds and small streams.

Ranging from 2¼ to 4¼ inches (snout to vent) in length, and green or bronze to olive-brown in color, its most distinguishing feature is a pair of parallel ridges or folds extending about 2/3 of the way down its back called the dorsolateral ridges.

Breeding males have bright yellow throats.  Green frogs can be confused with bullfrogs, but bullfrogs lack dorsolateral ridges, and full grown bullfrogs are much larger than green frogs.

It's common for the green frog's mating period to extend from early spring to late August, with more intense periods during May, June and July.  The mating call sounds like the twang of a loose banjo string, gungk, but explosive, either a single note or repeated 3-4 times, the notes progressively less loud.

Green frogs first mate when they are 1-2 years old.   Females lay up to 3,000 eggs connected in a thin gelatinous film that floats on the water's surface. After fertilization, embryos take about a month to hatch and transform into tadpoles. 

Metamorphosis from tadpoles to adult body form can take up to 1 year, depending on water temperature and food availability.

Green frogs can be found day or night depending on the season.  Males defend their territories actively at the edges of streams and ponds, and may physically or vocally attack intruders.

No discriminating palate here:  Northern green frogs will eat any living things they can capture and swallow!