From the April 2008 Conservationist
Photo: Bill Banaszewski
A rare glimpse into the world of a wintering mother bear and her cubs
By John Adamski
In the six years my wife and I had lived in Livingston County, we had black bears in the yard and on the deck 15 times. Other people got squirrels; we got bears. So one April, we called Department of Environmental Conservation (DEC) wildlife personnel, who live-trapped a female black bear in our backyard. Along with her two yearlings, this six-year-old sow had been raiding our bird feeders for several nights. Once trapped, she was sedated, examined, ear-tagged, fitted with a radio collar, and subsequently released.
The following year, after an intensive search using radio telemetry, the same bear was located and recovered from her winter den-along with two newborn cubs-just five miles from where she was initially captured. Under the direction of a DEC black bear specialist, the sow was once again sedated and prepared for examination. Because of our involvement in the previous year's incident, DEC officials invited us to attend and witness what proved to be a truly memorable experience.
What many people may not realize is that black bears do not truly hibernate. In fact, although they largely remain resting in their dens during the winter months, denned black bears maintain near normal body temperatures, allowing them to quickly respond to any situation. This includes reacting to biologists who visit their lair. Knowing that denned bears are generally aware of their presence, biologists are careful to quietly approach a known den site to avoid spooking the bear into fleeing. In most situations, the bear will remain in place. Not so during our visit.
Holed up in a largely open den, our bear, as we'd come to think of her, decided she'd rather be somewhere else. As DEC biologist Lou Berchielli crawled into the den with his tranquilizing prod, he sensed she was about to bolt out the other side. Prepared for this, Berchielli backed out and a wildlife technician quickly darted her. Once she was sedated, Berchielli reentered the den to retrieve the cubs.
The den itself was a cozy site excavated into the side of a shallow ravine beneath the mound of a slightly uprooted maple tree. Its entrance was hidden from view by limbs and branches left from an earlier logging operation. Without the signal from the bear's collar, it is unlikely that we would have found her den.
When previously examined in our backyard, this bear weighed 175 pounds; now she tipped the scales at 215 pounds. This added weight would sustain her through her long ordeal with new cubs, especially given that bears do not eat while denned, surviving instead on stored body fat.
Things are just the opposite with cubs. When born in mid to late January, naked and blind, they weigh just nine ounces, about the size of a small gray squirrel. At approximately six weeks of age, these cubs were doing well. The female cub weighed 6 pounds 4 ounces, and the male cub weighed an even 7 pounds-quite a testimony to the nutrition of mother's milk. By April or May, when they emerge from their dens, the cubs weigh about ten pounds. Before they den again next fall, these cubs will approach 100 pounds each.
While the mother bear dozed and unknowingly underwent her examination, the cubs reluctantly posed for pictures with DEC personnel and onlookers including my wife and me, who had the good fortune to be in attendance. Of course, the cubs were the center of attention. They complained about their interrupted feeding schedule with loud squeals that only hungry cubs can make. At six weeks of age, they already had sharp claws that would soon be used whenever mother ordered them up a tree to safety.
Toward the end of her examination, the sow began showing signs that the sedation was wearing off. After we repaired and refitted her collar and replaced a lost ear tag, we returned the sow and her cubs to the den, to continue the nurturing process.
These cubs were likely the sow's second litter. The area's rich habitat enables female bears to produce their first litter at three years of age and another litter every other year thereafter.
Wildlife staffers Art Kirsch and Greg Fuerst are at the forefront of western New York's bear projects. They are currently monitoring several bears, using radio telemetry and reports from people who see bears. A successful den visit makes Fuerst beam like a proud father. When he revisited the den a week later, the sow was nursing her cubs in the sunshine outside the den's entrance-a good indication that they were unruffled by their experience the week before.
Since 1994, regional staff have monitored more than 50 bears using radio telemetry. Biologists collect data on litter size, breeding age, survival and body weight. Beginning in 2002, DEC began using GPS satellite telemetry, enabling researchers to map home ranges with tremendous accuracy. They discovered that home ranges for adult female bears in western New York approach five times the size of bear home ranges found in the Adirondacks.
In the past decade, bear populations have expanded north from the Appalachians and western Finger Lakes into the Lake Ontario plain. However, major highways, high human populations and intense agriculture in this area may limit the growth of bear populations in the future. Lake Ontario is a barrier, quips Fuerst, who currently monitors four bears within sight of Rochester.
With more bears entering populated areas, the biggest concern shared by Kirsch and Fuerst is the interaction between bears and people. Ordinarily very shy and secretive, black bears generally try to avoid people. However, as bear populations expand, there is an increased chance of human-bear encounters.
Black bear activity is most noticeable in early spring when they emerge from their dens. After four or five months of fasting, finding food is their primary concern. Though they are New York's largest carnivore, surprisingly, black bears have a primarily vegetarian diet. Initially they'll graze, like cattle, to gently awaken dormant digestive systems, concentrating on succulent plants like skunk cabbage. Later they'll eat anything from honey to road kill. Opportunists, they will eat whatever is readily available, including human and pet foods. Sunflower seeds, especially the black oil variety, are high on their list of preferred foods and attract bears to backyard bird feeders.
If you have a bear visit your backyard, it's important to remember that they are wild animals, and although black bears are generally not aggressive, a sow with cubs can be unpredictable. Feeding bears-intentionally or otherwise-increases the potential for damage, injury or the necessity to destroy a bear. In the words of Greg Fuerst, "A fed bear is a dead bear." He notes that "after April 1st, bird feeders become bear feeders and should be taken down if bears are around." Of course, we had already discovered this the hard way.
I'll always remember my outing with DEC's bear biologists to track and study "our bear" and her cubs. It gave me a rare glimpse into a world few are privileged to see. Particularly noteworthy to me was the obvious dedication of these people, who are on the go at times 20 hours a day, seven days a week. They investigate every report of a bear sighting or bear damage and encourage people to report any such activity. However, Greg Fuerst does advise with a twinkle, "Please don't call me at home before 5 A.M.," to which his wife, Vicki, responds, "Thank you!"
Note: Visit DEC's website at www.dec.ny.gov/animals/6960.html to learn more about black bears in New York.
A former director of fish and wildlife management at Whitney Park, John Adamski is a freelance writer and wildlife photographer. His work has appeared in several regional magazines. This is his first Conservationist article. John is dedicating this article to his wife, Barbara, who passed away shortly after this outing.