In most competitions, gaining extra weight makes it harder to win. At Alaska's Katmai National Park, it may be exactly what earns a contestant the crown.
Fat Bear Week 2026 runs from September 22 through 29. This year's bracket features 16 brown bears that have spent the warmer months feeding along the Brooks River. In each round, two bears face each other and the public votes for the one that looks fattest and most ready for winter.
The contest may resemble a wildlife version of a talent show, but the weight gain is not just for entertainment. For brown bears, body fat is fuel. During hibernation, they live on stored energy and may lose as much as one-third of their body weight. Their survival depends on eating as much as possible while food is plentiful.
Salmon make that transformation possible. Viewers watching the park's live cameras can see bears standing in the river, catching fish and returning to the same feeding spots day after day. By early autumn, animals that looked relatively lean at the start of summer may appear almost round.
Fat Bear Week began as a one-day event in 2014. It has since grown into an international online tournament. More than 1.7 million votes were cast from over 100 countries in 2025. That total represents votes cast across the tournament, not 1.7 million individual fans.
Last year's champion, Bear 32, better known as Chunk, returned to defend his title. He joined other familiar heavyweights as well as less established competitors. There is no single scientific rule for choosing a winner. Some voters favor the biggest bear, while others consider how much an animal has changed or the challenges it has overcome.
The playful contest gives people a reason to follow individual bears, but it also draws attention to the ecosystem behind their size. Without healthy rivers and strong salmon runs, there would be no enormous bears to celebrate.
Humans often treat autumn weight gain as something to avoid. In Katmai, it is evidence of a successful season and a better chance of surviving the winter. For one week, getting gloriously fat is not a flaw. It is the whole point.