Alaska’s most anticipated wildlife competition has returned. Fat Bear Week 2025 officially kicks off today at Katmai National Park and Preserve, where twelve magnificent brown bears are vying for the ultimate title of fattest bear. Running through September 30th, this beloved annual tournament celebrates the incredible transformation these bears undergo as they prepare for winter hibernation.
What began as a simple one-day event in 2014 has evolved into a global phenomenon that captured over one million votes from one hundred countries in 2024 alone. The brainchild of former park ranger Mike Fitz, Fat Bear Week showcases the dramatic size differences bears achieve between their active summer season and their pre-hibernation peak condition in September.
“The astonishing salmon runs in Katmai are essential to the survival of the park’s ecosystem and brown bears,” explains Katmai Park Superintendent Mark Sturm. “Fat Bear Week enables people from around the world to actively engage in learning about bears while cheering for their favorite competitor.”
Bracket drops! Here are the opening matchups
The tournament kicks off with an exciting first round:
September 23:
September 24:
This year’s bracket features some compelling storylines. The competition includes 128 Jr., nicknamed “Biggie,” who already claimed victory in Fat Bear Junior earlier this week. This 1½-year-old cub, offspring of the legendary 128 (aka Grazer), represents both triumph and resilience after losing a sibling last summer. Her mother, a 20-year-old blonde bear, remains one of the park’s most recognizable residents. (She’s up later!)
Another notable contender is 32 Chunk, last year’s runner-up who dominated the river despite nursing a broken jaw — likely sustained during a territorial dispute with another male. His determination to continue fishing and bulking up despite this injury exemplifies the incredible drive these bears possess.
The competition also features 602, affectionately dubbed “Flow-tato” for his love of lounging by the river and his characteristic “stomping dance,” possibly performed when excitement levels run high. Meanwhile, 5-year-old 609, daughter of 909 and the 2022 Fat Bear Jr. champion, brings her distinctive large round ears and long nose to the bracket.
The tournament operates as a March Madness-style elimination bracket, with daily head-to-head matchups decided by public vote. Fans can cast their votes online daily between 12 p.m. and 9 p.m. Eastern Time at www.fatbearweek.org, while watching these magnificent creatures in their natural habitat, 24/7, through live cameras on Explore.org. (Literally, right now, you can watch them!)
With approximately 80 bears frequenting Brooks River during active season, only twelve make the final bracket based on criteria, including photographic documentation of their remarkable transformations. As park ranger Sarah Bruce notes, the competition makes this remote Alaskan wilderness accessible to people worldwide who cannot visit in person.
The champion will be crowned on September 30th, but every participant has already achieved victory simply by surviving and thriving in one of Earth’s most pristine wilderness areas.