American Bullfrog v Green Frog

Today I want to show two different frog species, both with similar coloring and size, the American Bullfrog and the Green Frog. These are both largish frogs that tend to stay close to water and are fairly abundant in central NJ. With quite a bit of overlap in size and coloring, the easiest way to differentiate them is that Green Frogs have a dorsolateral ridge on each side going from the eye down its back. The American Bullfrog has a ridge that starts at the eye, continues just past the eardrum, and then veers downward instead of across the back.

These frogs were both at Sourland Mountain Preserve. I was a little surprised that the small pond seemed to only have the Bullfrogs but when I went up the mountain to an even smaller pond I saw only Green Frogs. It's almost like these guys agreed to split the park up.

American Bullfrog
June 25, 2021 at Sourland Mountain Preserve
Photo 141961699, (c) jpviolette, some rights reserved (CC BY-NC)


Green Frog
June 25, 2021 at Sourland Mountain Preserve
Photo 141963199, (c) jpviolette, some rights reserved (CC BY-NC)

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