Yesterday afternoon, we spotted a couple banded woolly bears in a willow near the cabin. These are particular favorites of mine. A banded woolly bear is the caterpillar stage of the Isabella Tiger Moth. Here in Montana, the caterpillars emerge from eggs in late summer and early fall. They remain active and feed on broadleaf plants until cold weather sets in. When the weather begins to cool, the woolly bears seek out protected places in the understory: under deadfall, under leaves, or in root tangles. The woolly bears overwinter by curling into a coil and more or less freezing solid. Even the heart of the caterpillar stops beating. In the spring, the caterpillar emerges and pupates before becoming a moth.
Interestingly,
in the Arctic, due to the short growing season for vegetation, the woolly bear
must feed for several summers and freeze again each winter before becoming a
moth.
Folklore
holds that the thickness of the dark middle color band is a predictor of
winter. If the dark band is thin, the winter will be severe; if the band is
thick, the winter will be mild. The middle band, as a matter of fact, grows
wider as the caterpillar ages.
I’ve
written about them in two previous blogs, but don’t mind sharing again.
—Mitchell
Hegman



