It’s April, and that means outdoorsmen and women will be sharing the woods with newly active black bears.

Black bears live by the seasonal clock, hibernating generally from October through March.

The basics: Most will begin a light hibernation in October which deepens in November and continues through spring, though mothers will give birth in January. Black bears, especially the males, become active in April and mating takes place in June.

The North American Bear Center provides a detailed month-by-month look at black bear behavior and what you can expect from them.

Here’s a sample:

March:  Hibernation continues.  The testosterone (sex hormone) levels of adult male black bears begin to rise. 

April:  The snow melts and bears leave their dens.  Adult males leave their dens first while mothers with cubs are the last to leave their dens.  Food is very scarce.  Adult males begin to roam.  Most other bears remain lethargic (sluggish), eating mainly aspen catkins and willow catkins (pussy willows).  All bears lose weight at this time of year.

Find out more at Bear.org.