If you put all your skill points in hunting - which you can up to 30 - and don't address Wilderness Survival, Endurance, Body Building, etc... you'll be handicapped as a hunter to go out hunting only with those more experienced and more physically up to the task. Or you are limited to urban hunting and hunting in settled areas.
Butchering is part of Cooking. Food preservation is its own skill. Tanning the hide is Leatherworking. Hunting just covers killing the animal. You can earn points in Tracking and climbing and running etc in the course of hunting.