Two of these frogs are bullfrogs and one is a green frog. Can you tell the difference? Sometimes people think because one is bigger than the other that it must be the bullfrog but remember that bullfrogs start out small and green frogs can get pretty big.Often their markings are very similar. Some are dark, some are brighter green, some have blotches and spots or look warty....in both species. Frogs tend to be darker in the spring which helps them camouflage themselves in the darker water. As the greenery grows and the overall environment seems lighter the color of the frogs will also lighten up a bit.
Check out the ridge or line on these frogs. On one frog that lateral ridge goes down the two sides of the back. On the other two it just curls around the tympanum (big ear drum).
The top and bottom frogs are bullfrogs and the one in the center is a green frog. Bullfrogs have the ridge circling the tympanum and green frogs have the two ridges down their backs so no matter how big or small or how spotty or green they are, that is how to tell them apart. Special thanks to Mary Alexander for the use of her green frog photo. All the frogs I photographed the other day were bullfrogs.