Black Bears in Florida : Bear Facts - Hibernation, Breeding & Reproduction

The "Bear" Facts

Hibernation, Breeding & Reproduction

Do Black Bears Hibernate?

Black bears do not hibernate instead they experience what is often called 'partial hibernation' or 'winter lethargy'.

This period of reduced activity occurs in all black bear populations because winter lethargy is an adaptation to the lack of available food, not low temperatures.

Bears in southern states, from North Carolina south to Louisiana, den for shorter periods and sleep less deeply than bears in colder climates.

WhWhile denned bears in northern states are very lethargic and less responsive to people, bears in the South readily run away when people come close to their den.

What Makes a Den?

In Florida, males and non-pregnant females may den up in dense vegetation for only a few weeks or a month.

Pregnant females will den up for the entire winter, and because their cubs will be born in the den, they often select more protected sites.

Dens may be in tree cavities, under blow-downs or fallen logs, or ground 'nests' in dense thickets.

Breeding and Reproduction

The breeding season for black bears runs from June to July, but cubs are not born until late January to early February.

Bears have delayed implantation. If the mother is in poor condition and nutritionally stressed, the fertilized egg may be “reabsorbed”; the partially developed fetus will not develop further; or cubs will be miscarried and eaten by the female.

This adaptation to periodic food shortages prevents the sow from producing offspring for which she cannot care.

UnUnder normal circumstances, the fertilized egg will implant in November or early December, and grow normally until birth in about 8-12 weeks.

The Bear Cub

Bear cubs are very small at birth, only 225 - 450 grams (8 - 15 ounces) and the size of a small squirrel.

They have a very fine coat of hair but their eyes are closed. Litters range from 1 to 5 cubs, but 2 or 3 are most common in Florida.

The cubs nurse and play in the den until leaving in spring.

 Cubs stay with their mother for a year and a half, and will usually/almost always den with her the following winter.

Since bear cubs stay with their mother until the summer of their second year, young bears may be called either “cubs of the year” or dependent yearlings” when they are still with their mother, depending on their age and size.

During their second summer, the family group breaks up, the juveniles wander off on their own, and the adult female is ready to breed again.

FeFemale yearlings will likely establish their home ranges near or overlapping their mothers, while male yearlings will find new areas to establish home ranges.

Taking care of the cubs for 2 summers means that adult females will typically only breed every other year.