A fight between two brown bears at Katmai National Park and Preserve left one dead Monday, producing a gruesome scene on a popular live stream and postponing Fat Bear Week plans.

Officials at the park in Alaska confirmed an adult male bear identified as 469, a.k.a. “Patches,” killed an adult female, 402. The latter was a repeat contestant in Fat Bear Week, an online tournament that celebrates the bears as they bulk up for hibernation.

Following the bear’s death, competition organizers postponed a live chat event to reveal the tournament bracket originally scheduled for Monday night. The bracket will now be announced Tuesday night, organizers said. Fat Bear Week will still take place as scheduled from Wednesday through Tuesday, Oct. 8.

Fat Bear Week has brought international fame to Katmai and its resident bears, who are featured on webcams that have been live-streaming the area since 2012. More than 10 million viewers tune in to watch the bears during their bulking season, and around 1.4 million votes were cast in Fat Bear Week last year. Fans who cast their votes and comment on the live streams and dedicated social media channels hoped 402 would participate in the tournament.

Katmai ranger Sarah Bruce told The Washington Post they’re not sure why 469 fought to the death. Skirmishes between bears at Brooks are usually brief and end with opponents going their separate ways. This confrontation lasted roughly 20 minutes.

Explore.org naturalist Mike Fitz, who started Fat Bear Week in 2014, was not available for comment but shared his reaction on the camera’s message board: “We love to celebrate the success of bears with full stomachs and ample body fat, but the ferocity of bears is real,” he wrote. “The risks they face are real. Their lives can be hard and their deaths can be painful.”

The morning had started peacefully. Around 9 a.m. Alaska time, viewers of the “Kat’s River View” camera, one of the eight positioned around the area, could see at least four bears in frame, one sitting on the shore while others fished in the gray water.

Suddenly, two of the submerged bears – later identified as Patches and 402 – began grappling, biting and thrashing at each other. 469 eventually overtook his opponent, whose lifeless body sunk below the surface. Patches began eating 402, and later dragged her out of the water and out of the camera’s view.

“We don’t know why it happened … but it’s not unusual for bears to eat one another if the opportunity arises,” Bruce said.

Monday’s incident marks the second bear death caught on camera this year. In July, a bear cub crossed paths with 32 ‘Chunk,’ arguably the most dominant bear at Brooks. Chunk attacked the cub, who initially survived the attack but died days later.

402 never won Fat Bear Week, but she could be described as a queen mother. She had at least eight litters of cubs, and last season, she earned a reputation for defending her darling cub “Hedgie” against dangerous currents and savage adversaries. This fall, fans took notice of her impressive weight gain.

“I wanted this to be 402’s time to shine,” one fan wrote in the biggest Fat Bear Week Facebook group. “Such a beautiful huge girl.”

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