Length 1 3/4 – 3 in. (4.5-7.5 cm.) Although similar in appearance to the Northern Leopard Frog, the Pickerel Frog is slightly smaller, tends to be light brown instead of green, and has two rows of squarish rather than roundish spots running down its back. Also characteristic is the bright yellowish-orange coloration on the inside surfaces of its hind legs. Pickerel Frogs tend to favor the cool, clear waters of streams as opposed to the warm, sluggish waters of ponds and lakes. They occur throughout the eastern half of Ohio and all of the counties that border the Ohio River. They also inhabit the Great Miami River drainage from Logan and Shelby counties south to Miami and Greene counties. Many predators tend to avoid eating Pickerel Frogs. Their skin secretions are reported to be somewhat toxic, a trait apparently not shared by their close look-alike, the Leopard Frog.
Text courtesy of the Ohio Division of Wildlife: https://wildlife.ohiodnr.gov/portals/wildlife/pdfs/publications/id%20guides/pub348.pdf