Green frog, Rana clamitans
Oddly, green frogs (Rana clamitans) aren't always green. They can be green to bronze to brown, mixing it up to better blend into their watery environs. They are the second largest species found in our area, humbled in size by only those big, beefy boys: the bullfrogs.
You can find and hear both species in the Plaza Pond in front of the Visitor Center.
The bullfrog (Rana catesbeiana)