It was dark, warm, and humid last night when I opened my door to take my dog, Charlie, for a walk. We had to be careful not to slip on the wet cement as he went racing out to sniff the ground.
We walked the block to the sound of insects and frogs singing their little hearts out. I love when we get a few warm 60-degree days in the middle of winter. It brings out a chorus of frogs singing – like a promise of spring to come.
As we headed back up the steps to the door, I saw a tiny little frog sitting against the wall. A little spring peeper (Pseudacris crucifer) had come out to greet us.
I recognize these frogs by the cross-shape (X) on their back that helped give them their scientific name. They are very small and so cute!
Of course, I had to poke him to say hello (and to move him away from the door so we wouldn’t step on him). He hopped away from the door and back into the damp night.
This morning, I’m sitting here in my office watching flakes of this crazy looking white, fluffy stuff fall from the sky. It’s snowing! Today, the high is 39 degrees and that occurred at 6 this morning. It’s going to be a cold night!
Have you ever wondered what happens to the frogs in your backyard? From 64 degrees during the day to 20 degrees at night the following day is a dramatic change.
Being cold-blooded animals, frogs derive their body temperature from the air surrounding them. So, at 20 degrees, will they freeze and die?
Don’t worry – frogs have a way to cope with freezing temperatures.
Winter Hibernation
Frogs have a couple of strategies to deal with freezing temperatures. Many of our terrestrial (land) Mississippi frogs such as spring peepers and green tree frogs hibernate in deep cracks and crevices in trees, logs, rocks, or even just deep leaf litter and hide away.
Since these areas aren’t well protected from freezing temperatures, they may freeze and the frogs who have taken up residence there will freeze too. But they don’t die – even though ice may form in their body cavities and they stop breathing and their heart stops beating.
Frogs have high concentrations of glucose in their major organs that prevents these organs from freezing. As the temperatures warm up, these frozen frogs will slowly begin to move.
Frogs that live in the water (aquatic frogs) such as the American bullfrog (Rana catesbeiana) hibernate or go into torpor in the water. They spend the winter partially buried in mud or on top of the mud in areas of oxygen-rich waters for the winter. They must have enough skin exposed to the water to get enough oxygen in order to breathe.
On days when the temperatures rise well above freezing, our Mississippi frogs come out of hibernation long enough to sing out loud.
Apparently, it was warm enough, for long enough this week that the little frog that came to my door was hopping around looking for food. It brought me joy to see him! Now, back into hibernation he will go.
Check out this video by the Smithsonian Channel – it actually shows a frog becoming frozen!
This video by The Learning Channel has a time lapse of a wood frog defrosting