Skip to Main Content

Banded Woolly Bear Caterpillar (Isabella Tiger Moth)

Of the many species of moths present in Colorado, the Isabella Tiger Moth is actually much more commonly recognized in its larval form, the Banded Woolly Bear Caterpillar.  Often encountered as they cross roads and pathways in the fall and early winter, Banded Woolly Bears are as their name suggests banded with black and reddish brown.  Their fuzzy appearance and tendencies to wander are where their comparison to bears comes in.  Unlike a majority of caterpillars that cause plant damage by consuming foliage during the growing season in the spring and summer, Banded Woolly Bears cause less noticeable damage being that they feed late in the season (fall), when plants are getting ready to die off.  Banded Woolly Bear Caterpillars spend the winter in their woolly larval stage before changing into a beautiful white colored moth in the spring.  These caterpillars are also a part of folklore in that there is an old wives tale that the severity of winter is predicted by the width of their bands.  This is in fact a myth as the width of their bands is more likely related to the age of the caterpillar than the upcoming winter weather pattern.