A male American Toad (Bufo americanus) rests between calls with his vocal sac deflated.
The same male calls with his vocal sac inflated:
A pair of mating American Toads in amplexus. The male clings to the back of the female and fertilizes the eggs as she lays them.
These two male American Toads seemed to think my camera was a rival. They approached the camera while singing, possibly to chase it away from the breeding site.