VIDEO: DNR Biologists Count Cubs As Part Of Annual Den Survey

BALTIMORE (WJZ) -- Every year, Maryland Department of Natural Resources biologists perform black bear den surveys, which help them keep tabs on the size and health of the population in the state.

On Friday, they streamed part of the process live on Facebook. It involved a team sedating a mother in her Allegany County den and counting her cubs.

"Actually the most popular den site is a simple brush pile or under a blow down, a tree that fell over," says Harry Spiker, a state bear biologist. Getting to this bear family required a little more effort.

The mother made her den in a hollowed out tree trunk. She appears to have climbed about 12 feet high to access to a hole in the top of the tree, then climbed back down into the hollow part to hibernate and have her cubs. The team had to cut a hole into the tree to reach her and her babies.

She had four, one more than the average litter of three.

Judging by the overall healthy physical condition of the bear, "four cubs doesn't surprise me from her," Spiker says. Based on her teeth, she looks to be between 10 and 15 years old.

Spiker is part of a team who will be surveying the population for the next couple of weeks in Garrett, Allegany Washington and Frederick counties.

"It's important for us to know the sex ratio of the cubs," he says. While the mother is sedated, they count them, determine their sex, and they each get a physical from the veterinary staff.

They also "keep them warm while the sow is down and we're working with sow," Spiker says.

Looking at the health of the bears is also important, and Maryland Zoo veterinarians help with that effort.

"The Maryland Zoo helps us every year and we do some specific work to monitor the health of individuals and disease prevalence in the population," according to Spiker.

According to DNR, cubs are born in January with closed eyes and down-like fur, and weighing between a half-a-pound to a pound, about the size of a chipmunk. Sows typically give birth to between one to four cubs, who remain with her for 18 months before they set off to find their own territory.

Watch the part of the survey where they pull the cubs out of the den below.

See their other Facebook Live survey videos on their Facebook page.

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