Hibernating frogs and climate crisis

how warmer winters hurt frogs

Two Colorado River Toads. Image credit: kuhnmi (CC BY 2.0)

Depending where you live, it may not feel like we’re in a warm winter. We’re expecting snow tonight, with highs in the 30s this weekend. Long Island is bracing for a blizzard, and Boston is expecting up to two feet of snow!

But last month was our warmest December on record, making 2021 the fourth-warmest year recorded in the United States. Our average December temperature across the contiguous U.S. was 39.3 degrees F, which is 6.7 degrees above average.

Those are not frog legs. They are potato latkes!

Though a warmer December may not seem like such a big deal—Mamie fried our Christmas morning latkes outside, and they were delicious!—warmer winters are part of an overall trend that we can only call climate crisis.

Just look at frogs. So many frog species are already threatened by everything from habitat loss to droughts to a deadly (climate-worsened) fungus that frog extinction is the subject of chapter one of Elizabeth Kolbert’s The Sixth Extinction. Since the 1970s, more than 200 frog species have been lost, and 40% of amphibian species are threatened. But, as she points out:

Amphibians are among the planet’s great survivors. The ancestors of today’s frogs and toads crawled out of the water some four hundred million years ago, and by two hundred and fifty million years ago the earliest representatives of what became the modern amphibian clades—one includes frogs and toads, a second newts and salamanders—had evolved. This means that amphibians have been around not just longer than mammals, say, or birds; they have been around since before there were dinosaurs.

As we learned on Tuesday, frogs are so tough and resourceful that they can survive being frozen into frogsicles. That’s part of the frog playbook, at least for frogs living in temperate climates like ours.

But winters that don’t follow the rules, because of the manmade impact of burning fossil fuels and cutting down our forests (another threat to frogs), can be devastating.

Here are some things that can happen:

-With a late-starting winter (like this year), some frogs may remain too long on the edge of hibernation. This means they burn resources of fat and energy they can’t afford to lose. They may not survive the winter, or may be weaker in the spring.

-If frogs thaw out before they should, they can be killed during a re-freeze. This is called a “winter kill.”

-Frogs that start breeding too early often produce fewer eggs. They can also see their eggs and tadpoles killed by a re-freeze.

-Froglets that survive but mature earlier than they’re supposed to may compete for food with other animals.

-And, of course, short winters and warmer temperatures contribute to drought, which is hugely disruptive to frogs. As we saw when we rescued our puddle-bound tadpoles last spring and summer, they need stable bodies of water to breed and protect their tadpoles. If you find a very shallow body of water with tadpoles, you can keep adding non-chlorinated water to make sure the tadpoles survive, or you can raise and release them when they mature.

Right now you might be asking yourself, but you said above that frogs are tough, right? Frogs survive being frozen solid! For months!

But the thing is, that toughness and resourcefulness developed over time—millions of years. Because that’s the thing about nature—change is supposed to take a long time. But climate change is happening fast—and its impact is even more wide-ranging and problematic than even some scientists feared. That’s what makes it a crisis.

So what can you do to help frogs?

-Don’t use pesticides or herbicides.

-Don’t release pet frogs into the wild or collect non-native amphibians.

-Don’t drink bottled water (drink tap water instead).

-Reduce your use of plastics.

-Never disturb a hibernating animal.

-Eat locally grown food.

-Don’t eat beef.

-Call your representatives in congress.

-Build a frog pond at your home or school!

Read more about frog conservation and what you can do to help at Save the Frogs.

We’ll see you Sunday. Stay safe, Frog Troublers!