The Bronze Frog is actually the southern subspecies of the widespread Green Frog (Lithobates clamitans). In the northern parts of its range, the species is a bright green color but as you move south they become more and more brown in color. In the southeastern US they are largely bronzy brown in color.
Here is a pair from the same pond in Little Rock, Arkansas. You can see the varying amounts of green present. The male (with the large tympanic membrane) has some green on his face while the female (smaller tympanic membrane) has very little. This characteristic is variable but as you go north, the frogs get greener.
The call of Lithobates clamitans has been described as being like the "pluck of a banjo string". While this may be an apt description, it isn't a sound that many people are familiar with. However, it is probably the best description I have. To my ear, thesound is a percussive "dunk" or sometimes a double "dunk dunk" with the second "dunk" sounding like an echo of the first.
Bronze Frogs will often call sporadically from the side of a pond any time of the day. I have also found them to be quite shy and will often not call when you are standing near them. To get this recording is of a Bronze Frog from Little Rock, Arkansas, I found one sitting on the bank of a lake and set the microphone down near it and walked away. After 5 minutes, I can back and had three recordings from the whole time period. I have compressed them here so you can here them without having to hear the other 5 minutes of silence!
Here is a recording of a group of Bronze Frogs calling from a bottomland hardwood pond in the early afternoon after a brief rain shower.
Although the previous recordings have Bronze Frogs singing a single "pluck" note, many times when they are calling in a small group or alone you get a two note call. I've always thought it sounded like they were saying "Dont, Do" -
Here's the spectrograph of one of those "Don't, Do" calls -
I did finally get a recording of this species in Texas. Here's a single individual calling in Cherokee County (along with Gray Treefrogs, Cope's Gray Treefrogs, Blanchard's Cricket Frogs, Southern Leopard Frogs, and some distant "East Texas" Toads) -
and another chorus from deep Southeast Texas in Orange County -
© Chris Harrison 2015