Wednesday, August 28, 2013

Readers Write In: Is this a Pickerel Frog or Something Else?

Hey David –
My budding herpetologist and I are looking for your help again.
My daughter found this little girl the other night and we can’t figure out for sure what type of frog this is. I was leaning towards a Pickerel Frog but the edges of the spots aren’t as defined as I see in our frog book.
Our location is about 15 miles north of Atlanta. We are on a three acre pond but this frog was actually up by our backdoor near our garden if that helps at all.

Jeff G.
Roswell, Georgia

    By looking at the body shape of this frog, we can quickly determine that it is of the Lithobates genus, these are considered the "true frogs". When you ask most people to close their eyes and imagine a frog, they will think of a Lithobatid frog. Notice the large powerful legs (for leaping), robust body, and the long toes. This is definitely not a treefrog.

    Lithobatid frogs include the well-known species like Bullfrogs (Lithobates catesbeianus) and Bronze Frogs (also known as Banjo Frogs, Lithobates clamitans). The distinct markings on this frog eliminate those relatively drab and un-patterned animals and quickly lead us to one of two suspects.

   The Pickerel Frog (Lithobates palustris) can be found in the northern half of Georgia and the Southern Leopard Frog (Lithobates sphenocephalus) is found throughout the State. At first glance, they can seem quite similar. Leopard Frogs are generally more common and you can hear their chuckling calls at just about any time of year. Pickerel Frogs, on the other hand, have more specific habitat requirements. In some regions, just about the only place you can find them are in caves! But, they are not limited to these habitats, this spring I heard a few uttering their long, snoring-sound calls from the pond in front of my previous home in southwestern Virginia.

    Pickerel Frogs have two rows of square-like spots running down the back of their body while Leopard Frogs have spots that are generally circular and not always in rows. Pickerel Frogs also have bright orange spots on the back of their legs that Leopard Frogs do not have, but that doesn't help us here. As noted in a previous post, night photography can be tricky and deceiving. Similarly, Leopard Frogs generally have a light-colored spot on their tympanum (ear drum) but we can't see it from this angle.

   I have my guess, what is yours? I think this identification might be a little tricky because the patterning on this animal is a little unusual but I am confident we will come to a satisfying answer. If you have any, please share your tips for differentiating Pickerel Frogs from Leopard Frogs.  Guesses are welcome and encouraged!

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