Remember these guys? Freya, Oya, Athena, Aphrodite, et al? On a walk the other day, we passed the stream (pictured below) where we released a lot of our froglets last summer. It was now surrounded by snow, and many of the other streams and ponds around here have even been covered by thin sheets of ice. We haven’t seen any frogs since… at least November. I’m pretty sure you know what they’re doing…
Hibernating! Or technically, because they are ectotherms (they depend on the environment to regulate their temperature), brumating.
Like many animals, including bears, box turtles, groundhogs, garter snakes, copperheads, bats, and geckos, frogs go into a sleepy, dormant state when it gets cold and food becomes scarce. The lack of activity helps them survive the winter. But we wanted to know, what are they actually doing while they hibernate? So we did a little poking around…
Yes, literal poking around, along the banks of a pond. We weren’t trying to disturb anyone—if you happen upon a hibernating frog, definitely leave it alone!—but we were wondering if we might see one beneath the water. We read that, unlike turtles, most aquatic frogs don’t burrow into the mud—that would make it impossible to breathe. Instead, they find a quiet spot under a pile of leaves, beneath a log, or in the water. You can even sometimes see them very slowly swimming.
We didn’t see any frogs in our streams or the pond near the farmer’s market. But we did look up some interesting frog facts for you:
To prepare for hibernation, a single frog or toad may eat 10,000 insects during over the course of the summer!
Hibernaculum is the name of the hibernating space chosen by an animal.
Terrestrial frogs and toads hibernate on land. Very small frogs, like spring peepers, will hibernate in the cracks of logs, rocks, or in leaf litter.
Tree frogs often hibernate under the leaf litter at the base of trees.
Aquatic frogs, like leopard frogs and bullfrogs, hibernate underwater, on the bottom of lakes or streams. Their skin absorbs oxygen from the water.
Some toads will burrow in groups in communal hibernation spots, but most frogs and toads hibernate alone.
All hibernating frogs might freeze—but most frogs don’t die, even when their hearts stop beating and they stop breathing. This is because their cells contain a lot of glucose, which works like antifreeze to keep their organs safe. Here’s how the wood frog does it:
Then, in spring, they thaw out and are as good as new!
And if you want to dream about spring, just listen to these spring peepers:
We’ll be back Friday with more about how climate change affects hibernating animals, especially frogs.
In the meantime, here is a joke from Bea:
Q. What do you call the gossip of fungi?
A. Mush-rumors!
Did you know? Some non-migrating hummingbirds also hibernate when it gets cold! They enter a nightly state of torpor, which is like a very deep sleep. Their heart rate slows to 50 beats a minute (down from 1,250!), and their body temperature decreases from 104 degrees to 65 degrees.