Articles
Problems
Living with Bears: Many people are moving into black bear habitat. The bears’ future depends on how well we understand and tolerate them.
Misconceptions: People have demonized bears in many ways, giving bears an unrealistically ferocious image. People are unwilling to coexist with animals they fear, so they kill many black unnecessarily. A related misconception is that mother black bears are likely to attack people in defense of cubs. They are highly unlikely to do this.
Longevity & Causes of Death
Potential Longevity (lifespan): Black bears can live 21-34 years or more if they are not killed.
Causes of Death: In Minnesota, black bears less than 17 months old die from starvation, predation, falls from trees, and other accidental causes. A very few die from parasites or disease. 
Very few adult black bears die of natural causes except in national parks. Nearly all adult bears die from human-related causes. A few are killed by vehicles. Most are shot. The average age at which bears are shot in Minnesota is 2 for males and 3 for females.
Food & Habitat
Preferred Foods: Nuts, acorns, fruit, insects, succulent greens. Meat and less succulent greens are eaten when preferred foods are scarce. A scarcity of preferred foods can result in failed reproduction, stunted growth, failure to add optimal amounts of fat, and death of young bears, especially cubs.
Capabilities
Vision: Bears see in color and have good close-up vision. Distance vision (over 200 yards) untested.
Hearing: Exceeds human frequency ranges and is probably twice the sensitivity.
Smelling: Smelling ability extremely good. Limits untested. Their nasal mucosa area is about 100 times larger than in humans.
Activities & Social Organization
Daily Activity Period: Most bears become active a half-hour before sunrise, take a nap or two during the day, and bed down for the night an hour or two after sunset. However, some bears are active at night to avoid people or bears.
Core Home Range Diameter: Typically: Yearlings: 1-2 miles. Adult females: 2-6 miles. Adult males: 8-15 miles. Excursions to 126 miles recorded.