Fat Bear Week, an annual event held at Alaska’s Katmai National Park, is set to return, drawing attention to the park’s famous brown bears as they prepare for winter hibernation. Last year’s champion, a 1,200-pound male bear known as Chunk 32, is expected to make a comeback. Chunk, who suffered from a broken jaw and several other injuries—though the cause remains unclear—was still able to gain significant weight, ultimately winning the competition. According to park ranger Sarah Bruce, Chunk’s mandible, one of his canines, and front teeth were completely broken, yet he remained a strong contender. Park Superintendent Mark Sturm noted that this year, there are more cubs at Brooks Camp than in many years, hinting at a new generation of potentially hefty bears. Fat Bear Week runs from September 22 to 29 and is expected to feature around a dozen bears competing. The event, now in its 12th year, has grown from a small online poll to a popular annual tradition. In its first year, fewer than 1,700 people voted, but last year, over 1.7 million votes were cast. While there is no actual prize for the winning bear, the title is given to the one who "best exemplifies fatness and success in brown bears." The competition is both entertaining and educational, offering a glimpse into the bears’ dramatic physical transformations as they prepare for months of hibernation. During the summer and early fall, brown bears consume large quantities of food—primarily sockeye salmon—to build up fat reserves. Scientists estimate their weights using non-intrusive methods, as it would be difficult to weigh them directly. Adult female bears are typically about 50 percent smaller than males. Katmai National Park is home to approximately 2,200 brown bears, along with other wildlife such as moose, wolves, and bald eagles. Fat Bear Week was started in 2014 by former ranger Mike Fitz, who wanted to highlight the dramatic changes bears undergo as they gain weight in preparation for hibernation. The first full week of the event took place in October 2015, following an initial one-day event on Facebook. Last year, Chunk defeated a veteran bear known as “856” after previously losing to 128 Grazer, the first mother bear to win the title in 2024. Chunk’s earlier loss to 128 Grazer was likely influenced by an incident where Chunk attacked a cub that had slipped into his fishing spot, resulting in the cub’s death despite Grazer’s attempt to intervene. Voting for this year’s event will take place on fatbearweek.org, with sample polls already available on the website.