It's Fall, it must be migrating. . .

It's crisp, it's cool, it's Fall. It's baking season. I decided that I whip up a batch of lemon-poppyseed muffins. I dug out the classic Muffins and More, readied my ingredients and pulled out my mixer (best christmas gift ever). I looked in the bowl and what do I find nestled next to the beater? A small ball of black yarn. Does yarn migrate? If so, where does yarn go for the winter?