There are eleven different frogs found in Connecticut. They are the 1) Wood Frog, 2) Spring Peeper, 3) Bullfrog, 4) Green Frog, 5) Eastern Gray Treefrog, 6) Northern Leopard Frog, 7) Pickerel Frog, 8) Eastern Spadefoot Toad (Endangered), 9) American Toad and 10) Fowler’s Toad 11) Atlantic Coast Leopard Frog (extremely rare). I think you can easily learn to recognize all ten of these frogs either by what they look like or the calls they make.
We already know the wood frog is a tannish-brown color, has a mask, and sounds like quaking ducks.
Spring peepers are smaller than wood frogs. They are about 1 inch in length and only weigh .11 to .18 oz. They are tan or brown, have an X on their backs and large toe pads for climbing. Just like the wood frog their body freezes during winter hibernation. Five species of frogs can freeze and survive – spring peeper, wood frog, Eastern gray treefrog, Cope’s gray treefrog and Western chorus frog. The spring peeper will hibernate under logs or behind loose bark on trees. They are typically the first amphibians to emerge from hibernation. Just like robins and red-winged blackbirds, we refer to them as “harbingers of spring”. When we hear the males calling from ponds and swamps in mid-March we know the spring season is soon to arrive. It is amazing to hear the deafening chorus from the wetland areas and to think this little tiny frog is making all that racket!
If you are able to see a spring peeper you will notice that while they are singing their throat is inflated like a balloon. To make the call the peeper closes its nostrils and mouth and squeezes their lungs. This causes the vocal sac in the throat to inflate like a balloon. The peeping sound happens as air leaves the lungs, passes over the vocal cords and into the vocal sac. The call sounds like an ascending whistle. According to the USGS Frog Quizzes, where you can listen to the frog calls, the spring peeper sounds like a high, piping whistle. Large chorus sounds like sleigh bells.
The eggs hatch in 5-7 days after the female has deposited them singly or in clumps to submerged stems and twigs. Unlike the wood frogs they don’t appear to recognize their brothers and sisters. They mate and lay their eggs in water and then return to the forest where they spend the rest of the year. It is hard to see them since they are so well camouflaged.
They are nocturnal and carnivorous. At night, the adults feed on beetles, spiders, ants and flies.
Stokes Guide to Amphibians and Reptiles by Thomas F. Tyning
Amphibians and Reptiles of Connecticut and Adjacent Regions by Michael W. Klemens