Male frogs and toads advertise for females by calling loudly from bodies of fresh water. Some of them may also use their calls to defend territory.
Bullfrog
Rana catesbeiana
The male bullfrog is a basso profundo that calls from the edges of ponds and lakes. His advertisement and territorial call is said to resemble the bellowing of a bull. It often includes both a simple call and a stuttered call, as here. In New York it calls from May through August. (Albany, County, New York)
Frog, Green
Rana clamitans
The male's territorial and advertisement call is a twangy gunk which may be given singly or in a short series or three or four calls descending in pitch. Both version are heard in this recording (red-winged blackbirds and bullfrogs in background). When startled it gives a squeak as it jumps into the water. In this recording the splash is louder than the squeak. In New York it calls from May through August. (Albany, County, New York)
Frog, Wood
Rana sylvatica
The male's call has a quacking quality. Males call from vernal pools, small ponds, and roadside ditches for a short period in very early spring; the snow may still be on the ground. Their calls are not very loud in comparison to spring peepers, and if wood frogs are calling in the same place as a chorus of spring peepers, the wood frogs may be hard to hear. (Albany, County, New York)
Spring Peeper
Pseudacris crucifer
The male's advertisement call is a piercing, loud, repetitious peep. First part of the recording is a small chorus; the second part is a large chorus. It calls from vernal pools, ponds and ditches from early spring to early summer. It is remarkable that such a small animal can make such a loud sound; a large chorus can be deafeningly loud when one is close to it. To me, the distant calls of peepers in the early spring is a wonderful sound. (Albany, County, New York)
Toad, American
Bufo americanus
A breeding male's advertisement call is a long pleasing trill. Thoreau wrote that the toad's call "is a dreamy, lulling sound, and fills well the crevices of nature". Listen to toads calling at a distance, and you will see what Thoreau meant. Each male in a pond calls at a slightly different pitch. In the second segment of the recording, the trilling toads are accompanied by spring peepers. Breeds April to June in New York (Albany, County, New York)
Treefrog, Gray
Hyla versicolor
The male's call is a short trill. (The gray treefrog is almost indistinguishable visually from Cope's gray treefrog, but the call of the gray treefrog is more melodic and less harsh than Cope's). In New York the gray treefrog is heard from May through mid-summer. It may call from trees or bushes. (Albany, County, New York)