Reindeer can see ultraviolet light. "In areas where reindeer live, the sun remains very low in the sky for long periods. This means the light is scattered such that the majority of light that reaches objects is blue or UV. Some parts of the environment absorb UV light and therefore to UV-sensitive reindeer, appear to be black, strongly contrasting with the snow."
2. "On January 5, 2015, the camera caught a glimpse of a young white-tailed deer standing near the skeleton with a human rib bone in its mouth..." This was on a forensic science "body farm," but still... a deer?