Fat Bear Week
Fat Bear Week is a single elimination tournament where the public votes online for the fattest, most successful Katmai bear. The bear with the most votes advances and one winner is crowned Fat Bear Week champion.
Vote for the fattest bear of the year! Some of the largest brown bears on Earth make their home at Brooks River in Katmai National Park, Alaska. Brown bears get fat to survive and Fat Bear Week is an annual tournament celebrating their success in preparation for winter hibernation. Matchups are open for voting September 23-30 between 12 - 9 p.m. Eastern / 9 a.m. - 6 p.m. Pacific.
This is a single elimination tournament. For each match-up, vote for the bear you believe best exemplifies fatness and success in brown bears. The bear with the most votes advances to the next round. Only one will be crowned Fat Bear Week champion. Meet the bears, fill out your bracket, predict your fat bear winner, and campaign for your candidate.
Congratulations to our 2025 Fat Bear Jr Winner - 128 Jr!
This chunky champ has defeated 26’s female cub to claim the Fat Bear Jr crown.
Next stop: the big leagues — see 128 Jr take on the titans starting Tuesday 9/23 at fatbearweek.org!
Fat Bear Week 2025
Fat Bear Week is an annual celebration of brown bears preparing for winter hibernation in Katmai National Park and Preserve, Alaska. Each fall, the event showcases Katmai’s bears—especially those fishing along Brooks River—as they pack on pounds during a natural phenomenon called hyperphagia.
Hosted by Katmai National Park, Explore.org, and Katmai Conservancy, the bracket is revealed on September 22, and voting runs September 23–30, with the champion crowned on September 30. This single-elimination tournament invites the public to vote for the bear that best exemplifies success in getting fat to survive the winter.
What began in 2014 as a one-day event has grown into a global phenomenon, highlighting the resilience of brown bears, the importance of healthy salmon runs, and the vibrant ecosystems that sustain them.
Meet the bears and cast your vote at fatbearweek.org.