Autumn frogs on the move

“A frog he would a-wooing go, mm-hmmm, mm-hmmm.”
Well, you might see a lot of frogs around in the fall, but they are not going a-wooing at this time of year. They are wandering—in your garden, on the lawn, on the road, everywhere.
Why this sudden urge to travel? We aren’t quite sure, but it seems to be an instinctive behaviour to spread the species around—to extend their ranges.
Suppose there is a “frog pond” in an area. A lot of frogs breed there in the spring, and there are a lot of tadpoles. These eventually turn into little frogs.
But the pond and its surroundings couldn’t support all these frogs. So, in the fall, they get the urge to move. The lucky ones will be able to start life all over again in a new place.
This process not only helps frogs to move into new territory, it also reduces in-breeding, thus tending to keep the species vigorous and healthy.
To pass the winter, frogs bury themselves in the mud. But how do they stay alive all that time under the water?
Well, frogs are amphibians, which means they can live on land (in the air) and also in the water. In the spring and summer when they are living on the land (usually near water), they breathe with their lungs in almost exactly the way we do.
So they get their oxygen from the air.
However, during the winter, when they are buried deep in the wet mud, these lungs are of no value to them. But they have another method of obtaining oxygen.
They can absorb it through their skin, in much the same way a fish absorbs oxygen through its gills.
The frog, in winter, is in a state of suspended animation. It doesn’t move, so it needs no energy for that purpose. Its heart slows down to a very low rate.
Its requirements for food can be met by very slowly absorbing stored fat. All of its body processes are just barely “ticking over.”
So its oxygen requirements are extremely small, and this tiny amount easily can be absorbed through the skin from the water.
We have a number of frog species in this area. The common ones are the Leopard Frog, Green Frog, Pickerel Frog, and the Mink Frog. We also have the Wood Frog, which does not hibernate under water at all, but rather in damp places under rocks and stumps.
We also have, in some places, the Bullfrog.
The frogs are spreading around, seeking places to spend the winter. Then in the early spring, the a-wooing will really begin.
You will know it by the chorus of song produced in every swamp and pond in the district.

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