Reproduction and life cycle Bear

american black bears mating

the mating system of bears has variously been described form of polygyny, promiscuity , serial monogamy. during breeding season, males take notice of females in vicinity , females become more tolerant of males. male bear may visit female continuously on period of several days or weeks, depending on species, test reproductive state. during time period, males try prevent rivals interacting mate. courtship may brief, although in asian species, courting pairs may engage in wrestling, hugging, mock fighting , vocalising. ovulation induced mating, can last 30 minutes depending on species.

polar bear mother nursing cub

gestation typically lasts 6–9 months, including delayed implantation, , litter size numbers 4 cubs. giant pandas may give birth twins can suckle 1 young , other left die. in northern living species, birth takes place during winter dormancy. cubs born blind , helpless @ thin layer of hair, relying on mother warmth. milk of female bear rich in fat , antibodies , cubs may suckle year after born. 2–3 months, cubs can follow mother outside den. follow on foot, sloth bear cubs may ride on mother s back. male bears play no role in raising young. infanticide, adult male kills cubs of another, has been recorded in polar bears, brown bears , american black bears not in other species. males kill young bring female oestrus. cubs may flee , mother defends them @ cost of life.

in species, offspring may become independent around next spring, through may stay until female mates again. bears reach sexual maturity shortly after disperse; @ around 3–6 years depending on species. male alaskan brown bears , polar bears may continue grow until 11 years old. lifespan may vary between species. brown bear can live average of 25 years.