naked capitalism

Richard Smith says:

It’s a stoat. Related to otters and weasels. In the winter they go completely white except for the black tip of the tail that you can see in the photo. When they are white they are known as ‘ermine’. They are ferocious hunters and can kill and drag off rabbits, which are much larger than stoats. I have seen this – from a distance it looks like a rabbit moving along quite fast and erratically while having a fit; closer to you can see the stoat dragging the rabbit along, though dwarfed by it. They do a weird kind of dance to bluff their prey while closing in on it.

http://en.wikipedia.org/wiki/Stoat

bob says:

A few friend were ski touring in the chick-chocks in quebec when they stopped to rest. While they were stopped, a stoat, or weasel (description unclear) began harassing them at a close distance, climbing on their gear and running right up their legs looking for food.

They finished their snacks and got back on the trail. After finishing for the day, they were putting their packs in their car when one of them noticed the bag was moving. The weasel had hitched a ride 6 miles back to the car and was apparently eating the entire way. As soon as they opened the pack it ran out and away.

They found out later, at the bar, that it was pretty common there. They stay along the trails and follow people looking for food.