Every October when the weather turns crisp, thousands around the country tune in to watch a high-stakes tournament play out between fierce competitors, with one eventually crowned champion.

But we’re talking about bears, not baseball.

It is, after all, Fat Bear Week.

At Katmai National Park in southern Alaska, brown bears are winding down a stretch of nonstop eating, in which they gain hundreds of pounds to prepare for hibernation. They cavort and dive in Brooks Falls, feasting on migrating sockeye salmon and gaining up to four pounds a day.

The National Park Service has capitalized on the increasingly rotund population by live-streaming the hungry bears and creating an online bracket in which 12 of the park’s paunchiest are pitted against one another. Fans vote for their favorite bear in head-to-head matchups until the title of Fattest Bear is bestowed, this year on Tuesday.