2007-01-20 / Outdoors

Hibernating bears make excellent research subjects

Mother bears will be protective when their cubs emerge in the spring. Mother bears will be protective when their cubs emerge in the spring. Black bears in Cameron, Potter and McKean counties are hibernating, despite the mild weather of the early winter. That gives Pa. Game Commission researchers a chance to sneak into their dens and conduct scientific research.

Starting soon, and continuing until mid-March, the Game Commission will use telemetry equipment to locate dens of radio-collared female bears. Then, armed with tranquilizers, agency biologists will team with wildlife conservation officers to gather data about the adult bear, as well as the cubs. These visits are necessary to monitor bear reproduction levels.

Through these studies and other measurements, the PGC has determined that there are about 15,000 bears in Pennsylvania.

Even in hibernation, some bears -- mostly males -- will emerge from their dens on warmer days to move around before returning to their slumber. These activity bouts are not actually foraging trips. In rare instances, where food sources are readily available, a bear may visit the food, but it is usually only temporary.

Meanwhile, females are giving birth to their young this month, each weighing less than a half-pound. Litter size can range from one to five.

"Hibernating bears, unlike other hibernating wildlife, are awake and aware of their surroundings," said Mark Ternent, PGC bear biologist. "Females will groom their cubs daily, so hibernation for bears is more like a prolonged rest than a deep sleep."

In spring, when the bears leave the den, the female continues to protect the cubs, sending them up trees if danger threatens. By fall, cubs weigh between 60 and 100 pounds. Despite their ability to survive on their own, they'll usually den with the adult female for their first winter before separating the following summer.

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