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Nature Notebook – Wooly Bear Caterpillars

“My grandma and me have a contest to see who can find the most wooly bears. I’m winning. I’ve found six.”

Mid-fall is the perfect time for these intrepid caterpillar hunters. Most of the Isabella moth larvae (aka, wooly bear caterpillars) have reached their maximum size of two inches so they are easier to see. Their dark hairs absorb solar warmth so they bask in the open on walkways. They are also more active now. Instead of sleeping during the day and eating at night, they are searching for a hibernation spot.

The caterpillars spent all summer near marshes and damp meadows feeding on grasses, tree leaves (birches, elms and maples) and other plants such as dandelions, nettles, clover and asters. They moved around by using a strand of silk as a balloon or swing.

In spring the caterpillars will awake, eat, pupate and enter their short adult life stage.