One or two, and occasionally three squirrel-size cubs are born. By the time they leave the den in April or May, the cubs will weigh about 20 pounds. It's a remarkable growth rate when you consider that the cubs have been nursed for three months by a mother that hasn't consumed any foods or liquids. Spring When longer days, warmer temperatures, and melting snow signal the arrival of another spring, black bears emerge from their dens. Males are the first to step out, usually near the end of April.
Many black bears move to grassy south-facing hillsides as soon as they emerge.
These slopes are free of snow at this time of year and the bears find overwintered cranberries and bearberries on which to feed. At river level, fresh growths of horsetails and willow catkins are important spring foods. However, unlike grizzlies, black bears seldom eat plant roots. Most mammals are too fast for bears to catch, but moose calves are an exception. A two year study in the southwest Yukon revealed that black bears take from two to ten percent of the newborn calves.