You can learn a lot by what animals leave behind.  In this case, a bear was able to get a nice chunk of venison.  The size and the amount of hair (you can see the white and tan hairs closest to my foot) tells you that this bear took more than just a nibble at the deer.   Bear are one of the biggest predators of deer; especially deer fawns in the spring.  Clearly there is one less deer in this area then there was before winter started!