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Woolly Bear Caterpillar - will it survive inside?

My daughter found a woolly bear caterpillar. We live in Basalt, Colorado near Aspen. It appears, in doing some research, that this caterpillar will hibernate over the winter and morph into an Isabella Tiger Moth in the spring. My daughter wants to keep the Caterpillar in a terrarium and watch it evolve. I have told her that if we do that, it is likely the caterpillar will morph before the winter's end and if we release the moth, it will die once let outside in the middle of the winter.

Any advice on whether the caterpillar may hibernate inside a terrarium?

Please respond directly to

Thanks. Doug Leibinger and his daughter Brooke.

hibernating woolies
Though over-wintering wooly bear caterpillars is probably best in outdoor/garage conditions, my daughter insisted upon keeping a couple that we captured and fed towards the end of the fall here in MA. We don't have a garage or sheltered area outside to keep them, so they've been hibernating perfectly fine inside a jar on top of our microwave. They aren't disturbed, and have some dried oak leaves to keep them sheltered... and apparently that's just fine because they've been contently slumbering away since October/November. It seems so far that temperature has not been a problem with their hibernation.

To suggest an answer to your question, mother nature will probably keep wooly bears from an early metamorphosis. My woolies show no sign of waking early, and I expect they will remain dormant until spring, regardless of warm mid-winter conditions.

You could try overwintering it
but you need to try to replicate outdoor conditions. An unheated room/garage/porch would work best - you want to make sure it gets the signals it needs to complete pupation (which may be a gradual warming in spring, as it overwinters as a caterpillar). It wouldn't be my first choice for a caterpillar to keep inside, though - not much to see, as it's dormant all through the winter, but plenty of time for something to go wrong before pupation.

I'm assuming your caterpillar is the Isabella, by the way - other caterpillars are sometimes also referred to as Woolly Bears, though, so please confirm.

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