Bears generally live solitary lives, but can be found together during mating season. The average breeding age for female black bears is 3. Males reach sexual maturity at roughly the same age as their female counterparts.
Even though males are capable of breeding at three or four years of age, they rarely have the opportunity to do so because of intense competition from older, bigger males.
The biggest bears in the population tend to be the most prolific breeders. Not only are male bears promiscuous, but females often have more than one mating partner. Breeding season begins in May and lasts until early July, with mating mainly occurring during June. The implantation of the fertilized eggs — called blastocysts — is delayed until the start of denning season. If the female does not attain sufficient body fat or weight during the summer and fall, the embryos will not attach to the uterine wall and subsequently develop into little bears.
Cubs are born in the den in January or February. Litter size ranges from one to six, depending on the species and the productivity of the surrounding habitat.
Cubs weigh one-tenth as much as human babies and are born blind. Mother bears tend to be affectionate, protective, devoted, strict, sensitive and attentive toward their cubs, raising them to an age where they can survive on their own.
We do not receive any state or federal funding. Help support our mission. Click here to donate. Privacy Policy Code of Ethics. The 2-year reproductive cycle is genetically timed to fit the annual cycle of plant growth and fruiting… Read More ». Black Bear Litter Size How many cubs can black bears have? Three is most… Read More ». Cub Survival in Litters of 1,2 3, or 4 What size litter contributes the highest number of surviving cubs to the next generation?
The litter size 3 that contributed the highest… Read More ». Can Malnourished Black Bears Reproduce? In northeastern Minnesota, black bear females reproduce best… Read More ». Some territories contain… Read More ». Polar Bear Week. Life Cycle For female polar bears like Anuri, the cycle of life includes mating, denning, and giving birth to cubs. Photo: Kieran Mulvaney. Mating Spring Between April and late June, male polar bears search for female mates on the sea ice by following scented trails left by footpads.
After mating, adult males remain with the female for a few days before taking off on their own. Birthing Winter Wild polar bear cubs are most often born in December.
Polar Bear Cubs Totally dependent on their mothers, newborn cubs are blind, toothless, and covered with soft white fur. Emerging from then Den Polar bear families generally emerge from their dens in March or April when the cubs are strong enough to survive in outside Arctic conditions and make the trek to sea ice. Growing Up Polar bear cubs generally stay with their mothers for 2. Reaching Adulthood Polar bears are considered adults when they are old enough to mate.
Life Span In the wild, polar bears live an average of 15 to 18 years, although biologists have tagged a few bears in their early 30s. Name and Evolution Discover the many names for polar bears and how they evolved from brown bears. Continue Reading. Previous Name and Evolution Discover the many names for polar bears and how they evolved from brown bears. Feeling inspired? Act Now. Join us on our journey. Become part of a community committed to protecting polar bears with our free newsletter.
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