Who is Bear from Brian's Winter and what is their importance?

A bear comes twice to Brian's campsite. The first time, the bear is hungry and in search of the meal Brian ate the night before. Brian finishes the meat and washes the pot, but the smell lingers in the air. The bear attempts to kill Brian when he pushes at him, reminding Brian of the dangers of living alone in the woods. The bear then takes some of Brian's fish bait and fish. Later, another bear comes to the camp. The reader is not clear if this is the same or a different bear. This bear can smell the deer meat Brian has in his shelter and he attempts to steal it. However, a skunk living near Brian scares it away by spraying the bear. These attacks encourage Brian to make the larger bow and arrows and later the spear.