Fat Bear Week 2025 bracket challenge.

Brown bears have been hard at work feasting on salmon in the Brooks River, which means it’s time for one of the most anticipated weeks in the National Park Service: Fat Bear Week.

Every September, Katmai National Park and Explore.org partner to host this March Madness-style tournament, where bear fans can vote for their favorite fat bears. The tournament begins on Tuesday and the final will take place on September 30.

#32 Chunk, something big is coming. Photo: Christine Loberg

“For each match-up, vote for the bear you believe best exemplifies fatness and success in brown bears,” notes Explore.org. “The bear with the most votes advances to the next round. Only one will be crowned Fat Bear Week champion.”

Fat Bear Week is a great way for visitors to learn more about the biology of brown bears. As with all bear species, packing on the pounds in the summer and fall is necessary to survive the winter months when bears retreat to their dens.

You can participate by voting at this link.

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Heather Bergeson is a writer and editor based in Utah. Heather has written about travel, sports, business and the outdoors for Utah Life magazine, Utah Business magazine and Moab Sun News. She has a bachelor's...