Yellowstone: Bears Near Tower - Roosevelt

Black bear and cubs. 

Some elk, and black and grizzly bears, have learned that raising young near human habitation or transportation routes is safer because predators tend to avoid them. If naturally growing meals are plentiful, so much the better.

Then the rangers' problem becomes controlling the humans. The animals have preference. This female seemed unconcerned that 100 people were watching her from the road. Rangers were vigilant that she not be driven off by the foolhardy, of which there are more than a few around.

There is little-to-no human-generated food around the park to attract bears. The Park Service posts lots of notices about hiding food, using bear-proof trash containers, and not keeping food in tents. 

If a bear becomes habituated to finding food in town, it must be relocated. If it returns and does not return to the wild, it likely will be put down or, if it is lucky, moved permanently to a rescue and rehab center.