10 pts: Help me "define" my shapeshifter?

I'm torn between some large bird of prey or a slinky moutain cat. Maybe it would help to do some research on Native American totems and find one that might suit him there. As for birthmarks you can make it something related to his spirit animal but I'd be more inclined to make it something else - a predictor maybe of what his future might hold. Like how some culture's believe children born under certain star signs will have better luck that others.