-
Mating
The female grizzly bear will mate with several males if enough are in the area she inhabits. -
End of Mating Season
For most grizzly bears, mating season runs from May into the first part of June. -
Pregnancy
The bear gestation period varies between 180 and 266 days. -
Fattening Up for Hybernation
The embryo's development goes on hold temporarily at first, as the female gorges herself on whatever foods are available during the summer and autumn to develop a layer of fat off to live on through the winter months. -
Finding a Den
The female chooses the site of her den, often under a log, in a cave or in a hollow tree. -
Somewhat Hybernation
She will then proceed to enter a sort of stupor that is not a true hibernation, with her body temperature, heart rate and breathing all reduced. -
Growth of the Embryo
Once she is in this state, the embryo starts to develop once more, with the female giving birth to one to four cubs no later than March. -
Giving Birth to Cubs
The newborn cub lacks fur and cannot see until it's a few days old. -
Protection
The cubs will continue to stay with their mother for as long as three years. The cubs need her protection from predators such as other bears, cougars and wolves. -
Climbing
The grizzly cub has the ability to climb trees with ease until it is about a year old. -
Females Mate Every 3-4 Years
Most females will breed once every three to four years, as it requires a few years to integrate their cubs into the world. -
Young Adults
Once the cubs are capable of fending for themselves, the mother will drive them away from her and look to breed again. By this time the young grizzly weighs between 350 to 700 lbs. depending on the abundance of food. -
Growing
As these bears grow in size and strength, their diet will expand as they start to possess the ability to kill larger prey. These male grizzlies will wait until they reach their sexual maturity before they breed, with some mature at 4 years old and others needing as much as 18 more months to reach full adulthood. -
Territories
Grizzly bears will establish their own territories as they age. -
Cycle Begins Again
