HARTLAND, Conn. (CBSNews.com) -- In the woods of northern Connecticut, Paul Rego and his team of biologists led CBS News to a bear den.
Just under a fallen tree, there's a female black bear near the end of her winter hibernation. She's one of an estimated 500 black bears in the state. The men work their way in close and use a pole with a syringe attached to tranquilize her.
Last year, Rego's team put a GPS collar on the bear. The mission is to determine how bears travel, what types of habitats they're using and how often they reproduce.
Nestled with the mother were three cubs estimated to be three months old. The biologists will return in a year to check on whether they survived.
"We're finding the cubs, their first year of live, about 80 percent of them survive, which for a wild animal is really, really high," Rego says. "The adult females, their year-to-year survival is probably 95 percent."
The bear population is expanding into areas developed by humans, and humans are developing on lands used by bears.
The data obtained from the collar of the mother bear shows she spent the past year in and around developed areas.
"For some people, having a bear walk through your yard can be concerning," Rego says. "We have bears break into houses, kill livestock, attack pets."
While black bears are generally not aggressive toward people, they have something called a false charge.
"When they feel threatened, they'll actually charge a human being with no intent of completing the charge but trying to scare the danger away," Rego says.
A CBS News cameraman found that out when he got a little too close to another bear living in a shed near the local airport.
Biologists hope to educate the public about how best to live in harmony with their wild neighbors who are here to stay.