Make your own free website on Tripod.com
 
American Bears
 
Contents
 
American Black Bear
Habitat Preferences
Vital Statistics
The Hibernating Bear
Food Habits
 
Back to main page
 

 
 
 
 
American Black Bears
 
 
      American black bears are the most widespread and numerous bears in North America. They inhabit most of the continents forest areas, beginning at the Northern tree limit of the Arctic, south throughout much of the United States, and down the wooden Sierra Madre Mountains into the northern Mexico.  East and West, they range from Newfoundland to British Columbia's queen Charlotte Islands.
 
 
 
 
Habitat Preferences and Relative Abundance
      In all parts of their range, black bears prefer forests with intermittent open areas (meadows) that provide them with numerous berries and other desirable foods. They are most abundant in the mixed hardwood forests of the east and in the vast coniferous forests rimming the Pacific Northwest. They are least common on the Great Plains. It is difficult to accurately determine the number of black bears alive today. Some of our best estimates place the total population for all of North America somewhere between 400,000 and 750,000. (Because these estimates come from scientists, the numbers are probably rather conservative.
 
 
 
Food Habits
     Whatever its color, the American black bear is a four-legged garbage grinder when it comes to eating. Everything in the forest is a fair game. In the day they may feed on berries, animal carcasses, dead fish washed up on the shore of a lake, ants and other insects, acorns and beechnuts, wild cherries, honey (which they are extremely fond of), grass and herbs —practically anything edible. Research has shown, however, that these bears subsist mainly as vegetarians. Less than 25 percent of heir diet is composed of animal matter. Their food habits vary greatly with seasonal availability and location. Black bears on the West Coasts live primarily on berries, fish, and marine invertebrates found along beaches and in tidal pools. In Alaska, black bears kill moose calves and fish salmon. In northern Canada they eat lemmings when they can catch them. Food is a frequent cause of contention between black bears and people. These extremely intelligent and rather shy bears are the only bear species in North America that has adapted to civilization. To these bears, people and their belongings often mean just one thing that is "food". Cabins, camps, food caches, garbage cans, and town dumps are often raided by bears looking for an easy meal. Its amazing the amount of damage a hungry bear can do to a house or truck camper when it is trying to get in. I have seen entire walls ripped splinters by bears who smelled food on the other side.
 
 
Vital Statistics
    Black bears are the smallest of the Northern American bears. On the average, adults stand from 35 to 40 inches (89 to 102 cm) high when all fours and from 4.5 to 6 feet (1.37 to 1.82 m) in length, including a short tail some 5 inches 913 cm) long. Weighs are highly variable, ranging from 125 to over 600 pounds (57 to 272 kg). Size and weight vary considerably and depend on food availability in the area where the bear lives. Males are usually about a third larger than females.
 
 
 
The Hibernating Black Bear
     As fall approaches, black bears become very fat. In a frenzy of late- summer eating, they may gain as much as 30 pounds (14 kg) a week. This is their last chance to get in shape for winter. Just prior to denning time, the bears stop feeding, their stomachs becoming shrunken and half rigid. In this condition, the bears retire to a cave or hollow log and become dormant. Quite often they will drag leaves and tree branches into the hole to make a cozy nest. In the Great Smoky Mountains and elsewhere in the U.S. Southeast, most bears den above ground in tree cavities formed in wind damaged hardwood trees. Sleeping chambers are enlarged by scraping the cavity walls; the punky woods chips are then used as bedding material. Black bears in northern Canada den earlier and remain in their dens much longer than those in the South. After the first frost of September they seek out their den sites and are usually in hibernation by October. They emerge from their dens in late April, looking gaunt after their long fast. In Idaho, black bears dig their dens in October and enter in early November, remains there until mid April. In Florida, and probably in other Southeastern States, most black bears except pregnant females, remain active through the winter. (A northern bear that does not have sufficient fat for hibernating may also be active all winter.) Body temperatures of hibernating black bears range from 91.4 F to 99.4 F (33 to 37.4 C). Black bear blood has more , but smaller, circulating red blood cells than do humans or dogs. This condition appears to be an advantage to a hibernating species because it increases the surface area of its red corpuscles. This in turn provides a more efficient exchange of oxygen and carbon dioxide. Spring is a negative forage time for hibernating bears; the usually continue to lose weight for a couple of months after leaving the dens, or just maintain it if they're lucky. By the time summer's abundance arrives, life become a nonstop effort to eat and gain weight.
 
 
 
 
 


by: John Froilan Reyes