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Forget the election for now and consider the woolly bear caterpillar, inching its way to a safe winter haven

The banded woolly bear caterpillar we see around Chicago is the larva of the Isabella tiger moth. It’s wandering in search of a place to hibernate. And the ‘wool’ is for defense.

The woolly caterpillar is on the move, looking for a safe place to spend the winter.
The woolly caterpillar is on the move, looking for a safe place to spend the winter.
Peggy Notebaert Nature Museum

Where is the woolly bear going?

Surely, I am not the only one who wants to know.

If only I had more time, I could wait and watch until it gets there.

But there’s no time for watching caterpillars just now, not even cute fuzzy ones with black and orange stripes.

Leadership of our nation is at stake, and I must pay attention.

Still, the woolly bear seems to be everywhere I look these days, inching its way along purposefully if not exactly hastily.

I find them on the sidewalks and bike paths in my neighborhood and on the stepped cement “rocks” that pave the Lake Michigan shoreline.

It seems late for this migration. Shouldn’t the woolly bear have reached its destination by now?

The woolly bears crawling in the direction of the lake perplex me most. I fear no good can come of that. The woolly bear surely doesn’t swim, and I doubt it’s looking for a drink of water.

The temptation is to intervene, to trick the woolly bear into crawling on a stick and return it to the tall grasses where it won’t drown or get squished beneath a bicycle tire or somebody’s Skechers.

But I don’t want to interfere with Mother Nature.

We must have faith the woolly bear knows where it’s going, even if we don’t, right?

Right?

This is where you might expect me to turn the woolly bear into a metaphor for the election or the direction of our country.

But this is no metaphor. This is a diversion.

I could write about the election again, but then I’d get my blood pressure up or, worse, get your blood pressure up.

There will be time for that later.

Instead, I am trying to divert your attention from your anxiety with woolly bear caterpillars. But why them in particular?

It’s simple.

Try saying “woolly bear” aloud three times quickly.

Woolly bear. Woolly bear. Woolly bear.

See?

Doesn’t that feel better?

No extra charge.

But I still haven’t answered the question: Where is the woolly bear going?

For that, I turned to Allen Lawrance, associate curator of entomology at the Peggy Notebaert Nature Museum.

First, a confession: I thought woolly bear caterpillars turned into monarch butterflies.

Stupid, I now realize. I don’t know where I got that idea, the coloring maybe.

Allen Lawrance, associate curator of entomology at the Peggy Notebaert Nature Museum. 
Entomologist Allen Lawrance: “They’re kind of stuck walking for a while.”
Peggy Notebaert Nature Museum

Actually, the banded woolly bear caterpillar we commonly see around Chicago is the larval form of the rather undistinguished Isabella tiger moth — Pyrrharctia isabella to the scientifically inclined, which I clearly am not.

But before it can become an Isabella tiger moth, the woolly bear must find a place to survive the winter.

That’s why we commonly find it on the move this time of year, wandering about in search of a place to safely hibernate until spring.

Eventually, it will pick a sheltered spot under dead plant debris or inside a rock crevice to hunker down.

As Lawrance explains, the woolly bears have been chowing down for a while now in preparation for this moment. They’ll eat most any kind of plant. Then, a hormone kicks in that tells them the feast is over and to get moving.

“They’re kind of stuck walking for a while,” Lawrance said.

There are several theories to explain this wandering behavior. The one I like best is that they’re trying to get away from their poop.

Because they eat a lot, woolly bears also poop a lot, which predators can use to track their location. So, instead of spending the winter close to where they’ve been dropping woolly bear doo-doo, they go on walkabout.

Look, it’s a scientific theory.

Lawrance isn’t sure why they would be wandering so close to the water but suggests they might just be lost. If so, he says, they’ll either find a crack in which to spend the winter, or they won’t, our world having no shortage of woolly bear caterpillars.

Unlike some other moths and butterflies, the woolly bear doesn’t form a cocoon until spring, spending the winter as a caterpillar.

To survive the cold, it produces a chemical that serves as a natural antifreeze. The woolly bear’s fuzzy-wuzziness, which I mistook as a way to keep warm, actually serves as more of a defense mechanism, Lawrance said.

Before you activate your own defense mechanisms or need antifreeze, I recommend stepping away from your television and computer. The election fight will still be there when you get back.

Get outside. Take a walk. But be careful where you step.

The woolly bear’s life depends on getting where it’s going. And right about now, the destination is practically in reach.