Hazards of being a winter squirrel

We have a nice fresh snowfall on the ground. All bright white with a brilliant sun. We need the sun, it's nearly zero outside. Bunch of chilly squirrels scurrying about on the snow. Legs are too short to reach thru the powder snow and touch the ground, and they are so heavy that they sink right in. You can see 'em struggling in the deeper parts. They are all dark, and stand out on the brilliant white snow, making themselves perfect targets for any kind of hawk. Dunno what brought them out today, usually they hibernate thru the winter. If they were truly into being active-in-the-winter critters you would think they would grow white fur coats.