A beloved grizzly bear known as an ambassador for his species was fatally struck on a highway in Wyoming, National Park Service officials said Wednesday.

Grizzly bear 399, named through a research number assignment in 2001, was carrying a one-year-old cub when she was struck on a highway in the Snake River Canyon south of Jackson, authorities said. The boy's whereabouts are unknown, but there is no evidence that he was injured.

The driver is fine, officials said. Although the circumstances of the fatal accident were not immediately clear, authorities said 49 grizzly bears died in vehicle collisions between 2009 and 2023.

According to the Fish & Wildlife Service, grizzly bears generally live to be around 25 years old, although some in the wild are over 35 years old. Grizzly bear 399 was 28 years old when she was killed.

Wildlife photographer Thomas D. Mangelsen previously described the bear as his muse.

“Her intelligence, her behavior, her beauty,” Mangelsen told “60 Minutes” in 2018. “The fact that she had all these offspring. I don’t know many bears who have had three sets of triplets.”

In 2020, she was spotted with four boys.

Mangelsen isn't the only one who appreciates Grizzly Bear 399. People from around the world followed her for decades, said Hilary Cooley, grizzly bear recovery coordinator for the U.S. Fish and Wildlife Service.

“At 28 years old, she was the oldest known reproducing female grizzly bear in the Greater Yellowstone Ecosystem,” Cooley said.

Her identity was confirmed through ear tags and a microchip.

Before 1800, an estimated 50,000 grizzly bears lived in 18 western states, including Wyoming, according to the Fish and Wildlife Service. By 1975, the population in the 48 contiguous states had declined to 700 to 800.

After decades of being listed as threatened under the U.S. Endangered Species Act in the lower 48 states, the grizzly bear's population has grown to at least 1,923 in the 48 contiguous states.