Cocoon of a Woolly Bear, we believe

Subject: Mystery caterpillar
Location: Anchorage, Alaska
April 6, 2014 8:54 pm
My friend found this fuzzy black caterpillar, took it inside and it formed a cocoon! I’m sorry but I can only show a picture of the cocoon, no caterpillar. What is it, a moth or butterfly? Thanks!
Signature: Tam

Possibly Arctiid Cocoon
Possibly Arctiid Cocoon

Dear Tam,
What we can tell you for certain is that this Cocoon will produce a moth, not a butterfly.  We suspect by your description of the caterpillar and by the appearance of this cocoon, that it might be a Tiger Moth in the subfamily Arctiinae, and the caterpillars of Tiger Moths are frequently called Woolly Bears.  We decided to research the possibilities for a species identification and we found the Moths of Alaska website which contains a photo of the Wood Tiger Moth,
Parasemia plantaginis, but no photo of the caterpillar, though it is noted that “They overwinter in the larval form.”  That would explain your finding the caterpillar in April.  The Wood Tiger Moth is found “throughout northern Europe, northern Asia, and western regions of North America” according to Moths of Alaska.   We did locate a photo of the caterpillar on the Habitas site.  We are not certain the Wood Tiger Moth will emerge from this cocoon, but that is a distinct possibility.  Please get back to us when the moth ecloses, and provide a photo if you are able.  We don’t get many identification requests from Alaska, so we like to give them extra attention when the opportunity presents itself.

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