When the snow on the ground is 10” or more deep, and the night is very cold, ruffed grouse often seek shelter from the elements by diving into the snow and spending the night there. Sometimes they burrow five or ten feet into the snow, but sometimes, as in this case, they stay pretty much where they landed, perhaps a foot or so deep in the snow bank. This adaptive behavior not only hides them from predators, but serves to insulate the bird, as it rarely goes below 20 degrees F. in the cavity, regardless of how cold the air is. More often than not, the grouse defecates during its stay in the snow (dark matter in photograph). When leaving its snow cave, sometimes a grouse will burst out of the snow as it flies away, but as you can see from the groove in the snow in this photograph, this grouse chose to travel by foot.