Grizzly No. 399 and her cub during a rainstorm in early June. They were headed toward an elk carcass near Pilgrim Creek in Grand Teton National Park. (Deby Dixon)

Wildlife watchers and social media followers rejoiced last month when, at long last, a hulking female grizzly bear named No. 399 emerged from a longer-than-usual hibernation at Grand Teton National Park. Even better: Ambling beside her was a single, blond-faced cub.

There were two reasons for celebration. First, grizzly 399 was alive — a Wyoming hunter who had boasted of killing her months before had been bluffing. Second, the 20-year-old sow is, as a columnist for the Jackson Hole News and Guide put it, “the most famous living wild bear on Earth.” She has spawned 16 cubs, is a beloved “roadside bear” who’s easy for tourists to spot, has been the subject of a book and has a Twitter account. Even the hiker mauled by 399 and her cubs in 2007 pleaded for the grizzly’s life to be spared, and officials agreed.

And so great sorrow spread among the members of 399’s devoted fanbase on Monday morning when they learned that the bear’s cub had been killed overnight — by a car.

Grizzly No. 399’s cub, known to many as Snowy, walked through the Pilgrim Creek area in Grand Teton National Park last week. (Deby Dixon)

“The death of this cub is especially tragic since Grizzly 399 is nearing the end of her reproductive life,” Wyoming Wildlife Advocates wrote on its Facebook page. “399’s cub, known as Snowy or Spirit by the bear watchers of Grand Teton, was adored for its antics and notably white face and will be sorely missed.”

In a statement released later on Monday, the park said that the cub was one of two bears killed Sunday by drivers who did not report the collisions. An adult female black bear was fatally struck on the same road a few hours before 399’s cub, bringing the total number of Grand Teton animals killed by cars this year to 37, the park said. Vehicles have become a growing danger to wildlife in other parks as well, according to roadkill records released by Public Employees for Environmental Responsibility in 2013.

“These unfortunate incidents are an important reminder for all of us to slow down and be vigilant when we travel through the park,” said Superintendent David Vela. “Especially with the traffic levels that we are seeing during this busy season, it’s important to obey posted speed limits, maintain a safe following distance behind other vehicles, and be especially watchful around dawn and dusk when wildlife are more active.”

Deby Dixon, a wildlife photographer who recently wrote for Animalia about orphaned bison in Yellowstone, said she set out Monday morning to the spot on Pilgrim Creek Road where 399 can often be found. She hoped to take photos, but instead, she said, she happened upon what looked like an accident scene: The road was coned off, Dixon said, and members of the park’s volunteer Wildlife Brigade, which manages the roadside “wildlife jams” that occur when too many tourists stop to gawk at the animals, told her that the cub had become the victim of a hit-and-run.

Grizzly 399, Dixon said she was told, had dragged Snowy’s carcass to the side of the road. The park said its biologists found the carcass of the cub, which weighed between 40 and 50 pounds, about 40 yards from the road. They removed the body, which the park said will be “preserved and used for educational purposes.”

Grizzly No. 399 stood up at the Willow Flats area of Grand Teton National Park to survey the many tourists who had come out to admire her and her cub early one morning last week. (Deby Dixon)

Grizzly 399 rocketed to fame in 2006, according to National Geographic, when she was first spotted by the roadside, probably because it seemed safer than deeper in the wilderness, where male bears sometimes kill cubs. She was known for being particularly fertile, often giving birth to triplets.

Even in Grand Teton, though, life’s no picnic for baby bears. Thomas D. Mangelsen, who spent two years photographing 399 and her progeny for his book “Grizzlies of Pilgrim Creek,” told National Geographic last month that more than half of her cubs or descendants had already perished  — felled by other bears, or by run-ins with people.

“That shows just how precarious it can be to grow a bear population, even with remarkably fertile mothers like 399,” Mangelsen said.

Grizzly No. 399 and her cub played after crossing a road in the Willow Flats area of Grand Teton National Park. The cub was larger than most, and the pair played together often. (Deby Dixon)

But Dixon said this year’s cub was special, not only because it was incredibly cute and larger than most cubs.

“They would play like every other step,” Dixon said of mother and baby. “People who’ve been watching her for years have never witnessed her play with her cubs like that.”

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