I'm not saying this is your answer.... but.... I see blood in deer beds ALL the time. It's usually from yotes. They seem to like to stand in the matted snow as they munch on their kill.. Over the years.. I have found deer legs... feathers... and all sorts of animal 'pieces' in deer beds. My dog does the same thing too during a long walk.. she'll stop in a deer bed to take a breather.
Mike Ill keep an eye out for that. I dont get to shed hunt much in the snow because its ussually not around much here :D I wish it was not here at all
