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Black Bear
Behaviour
Feeding, Hunting & Foraging Behaviour of the
Black Bear
Black bears on the Pacific Coast frequent
beaches, estuaries and streams where they live largely on
berries, intertidal invertebrates and fish. They hunt salmon
returning to spawning streams during the day and night and
take their prey into the forest to be eaten. Estimates put the
total weight of salmon transported into the forest by an
average bear at about 1600 kilograms. Bears prefer the eggs
and brains of salmon so that much of the carcass is left
uneaten to decay in the forest. The nitrogen released from the
decaying salmon carcasses is recycled back into the trees as
they grow. The decaying trees release the nitrogen into the
streams to be used by young salmon.
Aggressive, Defensive & Territorial Displays of the
Black Bear
Black Bears are accomplished tree climbers
Black Bear Courtship & Breeding Behaviour
Mating: Every second year for females
First breeding: 2-9 years for females; 3-4
years for males.
Gestation: 210-220 days including delayed
implantation
Young male bears disperse from the natal
territory of their mothers at 1-3 years of age to seek out
their own territories. They begin to mate at about 3 or 4
years of age and continue to grow until they are about 10
years old. Females mate every second year and exclusively
raise the cubs. Mating occurs in early summer and delayed
implantation of the fertilized egg is delayed until autumn
resulting in birth in January. Newborns weigh 200-450 gms. No
other placental mammal gives birth to relatively smaller
young. The cubs suckle from the mother while she is in
hibernation although she is alert to their needs.
Families emerge from hibernating dens in spring
when the cubs weigh about 2-5 kg. They remain with their
mothers through the next winter or until the cubs are about 17
months old and their mother enters estrus. Yearlings weigh up
to about 50 kg at this time but some can be as little as 7 kg.
The range in weight is thought to be an adaptation to high and
low quality habitats by Black Bears
In the south, pregnant females hibernate
whereas in the north, both sexes hibernate for up to 7 months.
Bears do not eat, move around, drink or urinate during
hibernation. Small quantities of feces are produced and
metabolic rates drop by 50%. Pregnant females lose up to 40%
of their weight during hibernation.
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