<P> Sows usually produce their first litter at the age of 3 -- 5 years , with those living in more developed areas tending to get pregnant at younger ages . The breeding period usually occurs in the June -- July period , though it can extend to August in the species ' northern range . The breeding period lasts for 2 -- 3 months . Both sexes are promiscuous . Males try to mate with several females , but large , dominant ones may violently claim a female if another mature male comes near . Sows tend to be short - tempered with their mates after copulating . The fertilized eggs undergo delayed development and do not implant in the female 's womb until November . The gestation period lasts 235 days , and litters are usually born in late January to early February . Litter size is between one and six cubs , typically two or three . At birth , cubs weigh 280 -- 450 g ( 0.62 -- 0.99 lb ) , and measure 20.5 cm ( 8.1 in ) in length . They are born with fine , gray , down - like hair , and their hind quarters are underdeveloped . They typically open their eyes after 28 -- 40 days , and begin walking after 5 weeks . Cubs are dependent on their mother 's milk for 30 weeks , and will reach independence at 16 -- 18 months . At the age of six weeks , they attain 900 g ( 2.0 lb ) , by 8 weeks they reach 2.5 kg ( 5.5 lb ) and by the age of 6 months they weigh 18 to 27 kg ( 40 to 60 lb ) . They reach sexual maturity at the age of three years , and attain their full growth at 5 years . </P>
<P> Sows usually produce their first litter at the age of 3 -- 5 years , with those living in more developed areas tending to get pregnant at younger ages . The breeding period usually occurs in the June -- July period , though it can extend to August in the species ' northern range . The breeding period lasts for 2 -- 3 months . Both sexes are promiscuous . Males try to mate with several females , but large , dominant ones may violently claim a female if another mature male comes near . Sows tend to be short - tempered with their mates after copulating . The fertilized eggs undergo delayed development and do not implant in the female 's womb until November . The gestation period lasts 235 days , and litters are usually born in late January to early February . Litter size is between one and six cubs , typically two or three . At birth , cubs weigh 280 -- 450 g ( 0.62 -- 0.99 lb ) , and measure 20.5 cm ( 8.1 in ) in length . They are born with fine , gray , down - like hair , and their hind quarters are underdeveloped . They typically open their eyes after 28 -- 40 days , and begin walking after 5 weeks . Cubs are dependent on their mother 's milk for 30 weeks , and will reach independence at 16 -- 18 months . At the age of six weeks , they attain 900 g ( 2.0 lb ) , by 8 weeks they reach 2.5 kg ( 5.5 lb ) and by the age of 6 months they weigh 18 to 27 kg ( 40 to 60 lb ) . They reach sexual maturity at the age of three years , and attain their full growth at 5 years . </P>
how long do black bears live with their mother
how long do black bears live with their mother
16 -- 18 months
16 -- 18 months