Fat Bear Week delayed after a large bear kills a rival bear

Fat Bear Week, a celebration of brown bears’ survival instincts, brought a grisly reminder of the animals’ predatory nature on Monday, when a male bear, 469, killed a female, 402, at Katmai National Park & Preserve in Alaska.

The unsettling scene was captured by a popular live webcam that follows the bears on the Brooks River.

In a statement sent to NPR, the park said, “National parks like Katmai protect not only the wonders of nature, but also the harsh realities. Each bear seen on the webcams is competing with others to survive.”

The deadly fight took place around 9:30 a.m. in Alaska, as organizers prepared to kick off Fat Bear Week, the competition that lets fans crown the bear who successfully added the most weight as they prepare for their annual hibernation cycle. After the shocking death of 402, the unveiling of the 2024 bracket was delayed from Monday until 7 p.m. ET Tuesday.

As stunned viewers watched online, the two bears engaged in a lengthy and violent fight in deep water at the river’s mouth — a clash that eventually ended with one bear dying, and the other dragging her body ashore.

“Very difficult to see. I mean, 402 is a beloved bear by each and every one of us,” Mike Fitz, the resident naturalist with webcam company Explore.org, said in a video in which he and two Katmai Park experts discussed the incident.

“I honestly, you know, I think we're all in a little bit of a loss of words,” Fitz said.

Editor's Note: The video below depicts the bears’ deadly fight, and a discussion about their actions.

Both bears have been known to rangers for more than 20 years. 402 was “the mother of at least eight litters, more than any other bear currently at Brooks River. This includes two litters of four cubs apiece,” the national park said last year. In 2013, 469 won fans by overcoming a serious injury to his left hind leg and foot to fish at Brooks Falls. One year earlier, he was seen with an unidentified bear’s remains.

Fitz and the other experts — Naomi Boak of the nonprofit Katmai Conservancy, and Sarah Bruce, a ranger at Katmai National Park — said that while it wasn’t clear what prompted the clash, 469 came to see 402 as potential prey. 

“Whatever caused this initially stimulated a predatory or continuing predatory reaction by 469,” Boak said in the video, noting that 402, a well-known large female, was nearly as big as 469. “So she fought, she fought and continued to fight.”

The footage suggests that 402 died from drowning as she was overpowered, Fitz said.

“This is very difficult to watch and comprehend,” Boak said. She added, “we can feel these things but we can't anthropomorphize what's going on and assume that a bear's behavior is like our behavior. It's very different, these are wild animals.”

For those who enjoy watching the bears of Katmai Park, 469’s killing of 402 is a reminder of a stark reality: While the gigantic brown bears are oblivious to their roles in an annual online bracket, they’re also apex predators that are very aware of the competition for food and space — and raw calories.

“He's essentially predating on this other bear, he's a predator towards this female bear,” Bruce said.

“We do know that this time of year, bears are in that state of hyperphagia and they are eating anything and everything they can,” she added, referring to a condition described as an insatiable drive to consume food.

“I don't know why a bear would want to expend so much energy trying to kill another bear as a food source,” Bruce said. “It's an uncommon thing to see a bear predating on another bear. But it's not completely out of the question.”

In response to viewers’ questions, Bruce said that after the deadly fight, 402’s body was spotted in the woods, where 469 apparently placed it as a food cache. But another law of nature soon took effect: hierarchy. A dominant bear dubbed 32 Chunk ousted 469 and took over the carcass, Bruce said.

As for 469’s future, Bruce said rangers will not intervene.

"The park’s not gonna do anything to the bear, to 469,” she said. “You know, it's just kind of part of bear behavior and bear life. It's one of the sadder parts of it, one of the more difficult parts of it. But we're certainly just going to allow nature to play out as it does.”