http://www.youtube.com/watch?v=5Hmlb...p;sns=em<br />

My hubby and I just took some videos. Here is one. The Green frogs call sounds like a rubber band, the American bullies sound like a deep repetitive call.

Northern greens or Lithobates/Rana clamitans are smaller and have a ridge line along their sides from eye to about 1/3 or half of the side. Bullfrogs lack this line. Otherwise their markings are very similar.

Males call and their ear drum is larger than their eye, female's ear drum (tympanum) is smaller or equal to the size of their eye.

American bullfrog
Lithobates/Rana catessbeiana

My photo

Google images
Bullfrog (male)


Green frog (female)