"Black Bear Hunting Info. . .
. . . Reproduction"
Black bears breed from May through
August, with most activity peaking in June and July. Adults are
solitary, and during the summer months males travel over large areas
to enhance their chances for encountering mates.
Although males
become sexually mature at 1-2 years of age, most do not participate
in breeding until they have reached full adult size, at about 4-6
years in Maine.
Females in
Maine become sexually mature at 3-5 years of age. Individual females
have a 2-year reproductive cycle, which is related to their long
period of parental care for cubs.
Bears have a long gestation
period, but most fetal development is delayed until the final 6-8
weeks. Breeding occurs in the summer, prior to the fall feeding
period that provides the female with stored body fat to supply
demands for fetal development and her survival during the winter. If
a female is unable to store sufficient body fat, the pregnancy is
terminated.
Most fetal development occurs in early winter, after the
female has entered a den, and 1-4 cubs are born inside the winter
den during January - February. Cubs weight about 12 ounces at birth,
and depend on their mother for warmth and nutrition during the
remainder of the winter. They grow to 4-10 pounds by mid-late April,
when the mother leads them away from the den.
The family group
remains together for 16-18 months, until the female reenters estrus
and disperses her yearlings as another breeding season begins.
In northern Maine, fluctuating beechnut crops have produced alternating
years of high and low cub production, with most cubs being born on
odd-numbered years. Cub production is more consistent in central
Maine, where more stable fall food supplies result in nearly half of
adult females giving birth each year.
Longevity
Bears are long-lived animals, capable of
surviving 30 years in the wild. Their survival increases as they
mature. Nearly half of newborn cubs may die before reaching their
first birthday, with starvation being a major cause of death. By the
time bears in Maine reach 2 years of age their survival exceeds 90%,
and nearly all deaths of adult bears are due to hunting or other
man-related causes.
by Craig McLaughlin, Ph.D.
Wildlife Biologist
Maine Inland Fisheries and Wildlife
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