Black bears live by the seasonal clock, hibernating generally from October through March.
The North American Bear Center provides a detailed month-by-month look at black bear behavior and what to expect from them.
For example, most black bears begin a light hibernation in October which deepens in November and continues into spring, though mothers will give birth in January. Though still hibernating in March, adult males will experience increased testosterone levels and begin to rise.
Black bears become active, especially the males, in April. Adult males are the first to emerge while mothers with cubs are the last to leave the den. Because food is scarce when they first emerge, adult males begin to roam. Mating takes place in June.
Good stuff. Lots more available at Bear.org.