The average life span of grizzly bears is 25-30 years, rarely more. The mating period in the Grizzlies occurs from May to June. It is believed that males smell females, using such traces as wiping on trees. At this time of year, bears walk a lot, sniffing every corner of the forest to find a partner.
Often so deep in the search, that they forget to eat.
The female Grizzly does not immediately become pregnant, she can wear spermatozoa for months in her egg, waiting for suitable conditions for growing offspring. If the female has enough to eat and has reserves, then during the hibernation in the egg, processes may begin, but, if not, during the summer everything dies.
Bear cubs are born in the middle of winter, and their number depends on a rich local diet. Most often twins are born. Bear cubs are born blind and toothless, with a weight of 500 grams. They are so small that they fit into one palm, but they grow very fast, and until spring comes they become sturdy.