Fat Bear Week winner is revealed. She's a rebel.

Watch out.
By Mark Kaufman  on 
The 2023 Fat Bear Week winner, Grazer, seen in Katmai National Park and Preserve's Brooks River in September.
The 2023 Fat Bear Week winner, Grazer, seen in Katmai National Park and Preserve's Brooks River in September. Credit: NPS Photo / F. Jimenez

Welcome to Fat Bear Week 2023! Katmai National Park and Preserve’s brown bears spent the summer gorging on 4,500-calorie salmon, and they've transformed into rotund giants, some over 1,000 pounds. The Alaskan park is holding its annual playoff-like competition for the fattest of the fat bears (you can vote online between Oct.4 through Oct. 10). Mashable will be following all the ursine activity.


Many of the largest, most intimidating fat bears don't mess with Grazer.

She's not just one of the most dominant of the livestreamed fat bears, she's now the 2023 Fat Bear Week champion. The annual online competition hosted by Katmai National Park and Preserve allows you, the public, to choose the fattest of these Alaskan bears. It's a celebration of their success in the protected wilderness, a land where salmon still clog the streams, where lynx furtively peek from the woods, and where fat bears transform their bodies each summer.

These bears amass hundreds of pounds over the summer in preparation to outlast the harsh northern winter hibernation. The bears subsist on their fat stores for some six months; the more fat, the greater the odds of survival.

You can see the transformation of Grazer (formally numbered "bear 128" by the park) below. She grows into a large bear each year, big enough to challenge some of the largest males for the best fishing spots in Katmai's famous Brooks River. Her size, impressive angling skills, and unmatched aggression make her one of the most feared and respected bears in an ursine world where males often rule the river hierarchy. She subverts the order.

"Grazer is very dominant," Naomi Boak, the media ranger at Katmai National Park and Preserve, told Mashable.

Grazer's 2023 transformation.
Grazer's 2023 transformation. Credit: NPS / N. Boak / F. Jimenez

In years past, both rangers in the park and viewers on the livestreamed explore.org bear cams witnessed Grazer's fearless aggression. A few years ago, when Grazer had two cubs in tow, she charged bears that came close to her family. She even mauled a bear that attempted to steal a fish.

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In 2023, Grazer continued to successfully establish her presence at the Brooks Falls, where dominant bears hold dominion over the most prized and productive fishing spots. "She had no cubs this year, but she was still really dominant," Mike Fitz, a former Katmai park ranger and currently a resident naturalist for the wilderness livestreamers explore.org, told Mashable.

"Grazer is very dominant."

Grazer, packing aggression and reputation, regularly pushed a large male, Walker, from top fishing spots. "Walker avoided her," said Fitz. "Walker had enough bad experiences with Grazer in the past."

Grazer didn't just receive the public's Fat Bear Week endorsement in 2023; she also received Fitz's. "We’re fortunate to watch many different female bears at Brooks River in Katmai National Park. Yet there is one whose maternal efforts are legend," Fitz wrote before the October contest began. "One who can fish successfully almost anywhere. One whose fearsome reputation is long-lived among other brown bears, includ[ing] large adult males. Don’t get in her way. Don’t lurk near her fishing spot. Don’t look at her cubs. Do give 128 Grazer your 2023 Fat Bear Week vote."

She ultimately beat the extremely fat bear "Chunk" in the finals. This was no easy feat, for Chunk looked mighty huge this year.

Yet Chunk, like the rest of the Katmai fat bears, are all truly winners in their wild realm. They succeeded in enriching themselves off the park's resources, persevering over fickle salmon runs, aggressive competitors, harsh environs, and a rapidly ticking winter clock.

Grazer and the Katmai bears will occupy October plucking the last fish from the river. Then they'll dig their winter dens and spend months again transforming. They'll lose up to a third of their weight this winter, but if all goes as planned, emerge once again in spring, and trudge toward the river's bounty.

Topics Animals

Mashable Image
Mark Kaufman

Mark is an award-winning journalist and the science editor at Mashable. After communicating science as a ranger with the National Park Service, he began a reporting career after seeing the extraordinary value in educating the public about the happenings in earth sciences, space, biodiversity, health, and beyond. 

You can reach Mark at [email protected].


More from Fat Bear Week
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