I think this is a long tailed weasel. I was taking pictures of the tundra swans landing and taking off at the lake when I spotted a couple of ground squirrels running around. When I got a better look it was actually this weasel chasing a ground squirrel. He was a brave little fellow because I was snapping away and he didn't seem to be bothered by it. This is his winter coat but you can already see on his cheeks that the fur is starting to turn to brown which will be his summer coat.