Outdoor,
This is a phenonom that occurs in the Northern sttes and Canada. I had witnessed this in Northern Illinois. It usually is caused by the lack of available food in the area that they usually inhabit. The southern states where the winters are not so severe rarely see this happen. Most of the southern states usually have some forbs that can stand most marginal winter weather, maybe not the best, but sufficient to allow them to stay in their normal locations. That is a good reason to help them with winter hardy forage. A local game warden told us that one of the best would be to fertilize the local Honeysuckle. It's natural, withstands all but the harshest cold. It will grow wild in about any timber and does not need to be planted like food plots. It also helps in keeping the deer from bunching up which could spred diseases. During warmups I see a lot of mushrooms sprout, but I mostly see the remains of them where thay have been eaten by the deer. I, myself am glad that they do not "yard" like they do in the north.

Russ