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They Call It Home Frogs at the Homer Lake Wetland

Spring peeper calling at the Homer Lake Wetland. Spring peepers are the first frogs to start calling at the wetland, as early as the beginning of March. Spring peepers and boreal chorus frogs, the second frog species to start calling shortly after the spring peepers arrive, both have the ability to survive freezing temperatures by accumulating lots of sugars in their cells, a kind of antifreeze to prevent damage to the cells, and by going dormant -- to the point that their hearts actually stop beating.

American toads together with the spring peepers and the boreal chorus frogs are three of the NINE frog and toad species that show up at the wetland to breed. The raucous calling of the various frog species from early spring into midsummer is the work of male frogs and toads competing for the attention of the females of their species.
The northern leopard frog is another species that shows up in early spring to call for mates. Unlike the one large vocal sac under the throat of the spring peeper and American toad pictured above, leopard frogs have two vocal sacs, one on each side of the throat. Though the vocal sacs themselves cannot be seen in the photo above, the sound vibrations in the water can be seen spreading in two semicircles, one on each side of the frog. The northern leopard frog was first documented in Champaign County in 2021 at the Homer Lake Wetland, a new county record.
With all of these calling frogs, of course there will be frog eggs in the water. These are leopard frog eggs -- either northern leopard frog or plains leopard frog, both of which breed at the wetland. These eggs are at an early stage of development.
These are boreal chorus frog eggs at an advanced stage of development, approximately 24 hours before hatching. Young tadpoles can be seen in most of the eggs, though a few eggs have not moved beyond the round ball stage.
The prettiest tadpoles (in my opinion) that hatch in the wetland are the gray treefrog tadpoles but below are a couple of other species for the sake of comparison. Like other frogs that breed successfully at the wetland, these tadpoles must make it to maturity before the wetland dries up, typically in late summer.
Spring peeper tadpole on the left and Blanchard's cricket frog tadpole on the right. Both have sprouted their back legs but not yet their front legs. Interestingly, scientists have determined that the Blanchard's cricket frog tadpoles have clear tails when they are in ponds that have no dragonfly naiads but have black tail tips in ponds where dragonfly naiads are present. The naiads are voracious predators and it seems the black tail tips may serve to draw the naiad's attention away from the tadpole's head to increase the tadpole's chance of surviving an attack.
This is a green frog tadpole. Green frogs and bullfrogs both breed in the wetland; however, unlike the other species that breed there, they require two seasons to mature and so have to overwinter as tadpoles. Given that in the vast majority of years the wetland goes dry in late summer for some period of time, most years the green frog and bullfrog tadpoles at the wetland do not survive to adulthood.
This is a gray treefrog tadpole that has just about made it. It has all four legs, but still has its tadpole tail and so far is still breathing through gills, getting its oxygen from the water rather than from the air.
This is a spring peeper "metamorph" -- a new little frog, which as you can see, still has its tadpole tail but has begun breathing air and started its life on land. Quick development from tadpole to frog helps assure that they reach maturity before the wetland dries. Spring peeper and boreal chorus frog metamorphs are typically coming out of the water in early June. The fact that they are still very small when they emerge helps with the speed of their metamorphosis. They seem to put most of their energy into changing into frogs rather than getting bigger. American toads also emerge as "toadlets" extremely small and as a consequence develop very quickly.
Boreal chorus frog "froglet" demonstrating its very small size at metamorphosis. This little guy has lost his tail but is still very small and will be moving away from the water until next year's breeding season.
Adult gray tree frog chillin at the edge of the wetland. Gray treefrogs spend most of their time -- where else but in the trees? When breeding season rolls around though they make their way to the local wetland and can sometimes be found hanging out in that area snoozing the day away as they await a busy night of calling their little hearts out.
It is worth mentioning that gray treefrogs can change their color and are sometimes green, despite their name!

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The Homer Lake Wetland Blog -- observations of the wetland and the things that live there from March through November 2021

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Text, Photos and Videos by Doug Mills