Canon 7D, Canon EF70-200 f/4L IS (@200mm). 1/1600sec, f/5.0, ISO360. Cropped in a bit. Shot from my car during our Christmas Eve day snowstorm. Feeding under one of our bird feeders. He's so well insulated the snow doesn't melt...
Steven, Maureen's right...If you open your image and then open a levels adjustment you'll see the white slider with no data underneath it. In an image with snow so prominent, there should be some white data! I scooted that slider in to around the 210 mark and then scooted the midtone slider left to 1.10 and that brought out the snowy whites a bit better.
Very nice composition here and a good aperture as you got lots of detail in the squirrel without much BG getting in the way. If you could have eliminated the black area totally that would have given the image a more consistent feel but then we'd have missed the white snow falling so it's your call!