As a spring snowstorm barreled into Jackson Hole, Wyoming, on May 16, three figures ambled down the road, the mighty Teton mountains towering behind them.

Grizzly bear 399, arguably the most famous wild mother bear in the world, had returned yet again to her familiar haunt, Grand Teton National Park, and, in doing so, added one more chapter to an already legendary story.

Now 21 years old—ancient in bear years and well beyond the age when most female bruins typically breed—399 had two bouncy cubs in tow.

In 2016, 399’s white-faced cub Snowy had been killed by a car in the same area, the Pilgrim Creek drainage. Her fans had speculated for months whether the mama bear was still alive, but few expected her to have another baby—much less twins.

When wildlife photographer Thomas Mangelsen, who has spent a decade documenting 399, saw a video of the family, he choked up.

“I had a hunch she would show up one more time, but in nature there are no guarantees, and it’s not easy being a grizzly in the modern world,” says Mangelsen, who featured 399 in the book Grizzlies of Pilgrim Creek. (This author wrote the book's narrative.)

“Every year that 399 has remained alive, raising successive broods of cubs, staying out of trouble with people, has been for those of us who enjoy her presence a gift and a miracle. After Snowy’s death we prayed she might make an encore.”

Bear Baby Boom

Born in 1996, 399 has been part of a wave of bear recolonization pushing out from nearby Yellowstone National Park into wildlands where grizzlies had been largely eradicated for half a century. (See a bear's-eye view of Yellowstone.)

As a calm mother who often brings her cubs around people, she has become a favorite of many and even an ambassador of sorts for her much-maligned species.

In her two decades of life, 399 has given birth to three sets of triplets, one set of fraternal twins, and two single cubs. Her daughter, identified as 610 by researchers, has also raised four cubs of her own; 17 total cubs descended from 399: 18 total bears if you count her.

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Every bear is crucial for a species listed as threatened on the Endangered Species Act. Today, estimates of the number of grizzlies in the 22.5-million acre Greater Yellowstone Ecosystem (which includes Yellowstone and Grand Teton National Parks) range from 600 to upward of a thousand.

Connection to Wildness

But as many as half of her descendants have been killed in different kinds of conflicts with people. Few live long enough to die of old age. Overall, 85 percent of grizzly deaths in the Greater Yellowstone area are related to humans.

For instance, huge traffic congestion events called “bear jams” have become regular fixtures in Grand Teton. On May 16, while 399 and cubs crossed the road, motorists ignoring speed limits roared within feet of the family, showing how perilous it can be along the roadside. (Read: "What's Next For Yellowstone's Grizzlies?")

Yet while government wildlife managers are concerned about the commotion caused by bear watchers, it’s important for national park visitors to be able to experience the wildlife.

In Grand Teton National Park, wildlife watching is an economic engine worth more than $728 million. A 2014 study found that national park visitation in the United States would decrease about 5 percent if bears were banned from roadside habitats.

“People from several different counties have been sending me emails and notes all winter wondering if I knew anything about 399,” says Bernie Scates, who shot a video of the family on May 16.

“399 is their connection to wildness, and they are cheering for her and the cubs.”

“She’s Still Here”

Last fall, before 399 vanished back into the forest, one indication gave Mangelsen reason for optimism.

The bear looked heftier than the wildlife photographer had ever seen her. She was also seen in the company of two male suitors—a massive boar nicknamed Brutus and a smaller one called Bruno, both believed to have fathered some of 399’s past cubs. (See National Geographic's bear pictures.)

“You come to know her, respect her, value her as a mother teaching her cubs how to navigate a dangerous world,” Mangelsen says.

“We’re all celebrating this week. She’s still here!”