Detour around areas where you see or smell carcasses of fish or amimals or see scavengers congregated. A bear's food may be there and if the bear is nearby, it may defend the cache aggressively. Give bears plenty of room. If you stray within that zone, a bear may react agressively. When photographing bears, use long lenses getting close for a great shot could put you inside the danger zone.
Female bears can be fierce defenders of their young.
Getting between a female and her cubs is a serious mistake. A female bear may respond aggressively to any threat she perceives to her cubs. Bears Are Always Looking for Something to Eat Bears have only six months to build up fat reserves for their long winter hibernation. Don't let them learn human food or garbage is an easy meal. It is both foolish and illegal to feed bears, either on purpose or by leaving food or garbage that attracts them.