Is the Banded Woolly Bear Caterpillar Poisonous? And Other Facts to Know

banded wooly bear caterpillar on a rock

Have you ever seen a cute, fuzzy caterpillar and then had someone warn you that all fuzzy caterpillars are poisonous? Although it is true that many fuzzy caterpillars are dangerous to handle, making a generalization about all of them is wrong. 

You’ve come to the right place if you’re wondering, “Is the banded woolly bear caterpillar poisonous?” Keep reading for the truth on the matter from our insect experts

Is the Banded Woolly Bear Caterpillar Poisonous? 

We’re going to begin by answering your most pressing question.

Q: Is the banded woolly bear caterpillar poisonous?

A: No, banded woolly bear caterpillars are not poisonous or venomous. 

Some varieties of fuzzy caterpillars are unsafe to touch because they have sharp spine-like hairs that can puncture the skin, be painful, and excrete venom. On the other hand, banded woolly bears have no poison, venom, or harmful appendages on their body.

Before you touch a fuzzy caterpillar, make sure you identify it correctly.

What Do They Look Like?

In order to properly identify a fuzzy caterpillar as a Banded Woolly Bear, you’ll need to know specifics about what they look like.

There are multiple types of “woolly caterpillars” that come in a variety of colors and are the larvae of different types of moths, and a few have the harmful spines and venomous secretions we mentioned in the previous section. The kind we’re discussing, specifically the “Banded Woolly Bear” caterpillar, are spine-free and harmless, and they’re orangey brown and black, like this: 

image of banded woolly bear caterpillar on a branch

As you can see, the fuzz on Banded Woolly Bear Caterpillars is mostly black, but they have a wide rust-colored band running horizontally on the middle of their back. If you didn’t know, an old wives’ tale says the length of the orangey-brown and black bands of fuzz on these guys during the summer and fall predicts the severity of weather in upcoming winters (National Weather Service).

Although we’re no meteorologists and cannot confirm the feasibility of this folklore, we can say for sure that the Banded Woolly Bear Caterpillar is the Isabella Tiger Moth in its larval stage (behold their winged beauty in the next image). 

picture of an isabella tiger moth on a flower

Why Are Their Bands Relevant?

Let’s face it: it is unrealistic to believe that how much brown or black is on these fuzzy little creatures accurately predicts the severity of forthcoming winters. 

The two reasons of significance for their bands, however, are entirely separate from the wives’ tale. 

#1: The brownish band makes Banded Woolly Bear Caterpillars visually distinct from other types of woolly caterpillars that are dangerous (e.g. the Bag Shelter Caterpillar Ochrogaster lunifer, the Puss Caterpillar Megalopyge opercularis, and the Hickory Tussock “White Woolly” Caterpillar Lophocampa caryae).

#2: The bigger the brown band is, the older and closer to pupation the Banded Woolly Bear caterpillar is. Each time it molts in the larval stage, the brown band gets longer, taking up more of its body.

Why Are They Fuzzy?

You may be wondering why Banded Woolly Bear Caterpillars are fuzzy if their hairs (bristles) aren’t poisonous. The reason is mainly because the fuzzy bristles make it more difficult for birds and other predators to grab and eat them. 

What Makes Them Unique? 

When winter is getting close and more and more of their fuzz is brown, Banded Woolly Bear Caterpillars hibernate for the winter while still in their larval stage. Once spring rolls around, they’ll wake up from hibernation and then pupate (form cocoons). They develop in the cocoon for a couple of months, and then when summer arrives, they’ll emerge as beautiful Isabella Tiger Moths.

Why Do We Talk About Caterpillars?

We’re pest control agents, so why are we talking about harmless, non-venomous fuzzy caterpillars? 

One reason is our role in ensuring the safety of families in Birmingham, who count on us for their news and information on all types of insects. We want to reassure you that there’s no threat to handling Banded Woolly Bear Caterpillars. 

The other reason is that, despite being adorable, many varieties of caterpillars are agricultural nightmares. Their larvae quickly decimate home gardens and large fields of crops that are grown for human consumers to buy from the grocery store.

The great thing about Banded Woolly Bear Caterpillars is that they rarely infest, let alone cause noteworthy damage to crops. They mostly eat weeds and grasses. 

Your Guide to All Things Insects 

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For 40+ years, our team of integrative pest management professionals from Vulcan Termite & Pest Control has proudly aided hundreds of families in Birmingham and nearby communities by investigating and solving problems with pests on their property. 

We’ll gladly perform a FREE evaluation and create and implement an effective strategy using our tried-and-true methods, so you and your family can enjoy a pest-free home.

Are you curious to keep learning about common critters found in Alabama or how to safely and humanely deal with them when they show up on your property uninvited? Check out more of our weekly pest blogs for helpful tips, tricks, and educational content!