What started as a one-day tournament called Fat Bear Tuesday on Facebook in 2014 has now expanded to an entire season.
Fat Bear Season runs from late June to late September or early October when it culminates in Fat Bear Week. A one week celebration of the brown bears of Katmai National Park where individuals around the globe can vote to decide which bear will be crowned the winner of Fat Bear Week.
Last year’s Fat Bear Week captured over 1.7 million voters who decided which of the twelve bears will be crowned champion in a bracket style tournament to determine the crowd favorite. The bears, which start the season at roughly 600 pounds eat up roughly fifteen salmon per day to gain roughly 400 pounds. Last year’s winner bear 32, affectionately known as Chunk, weighed in at approximately 1,200 pounds; finally cinching the title after being the runner up in 2023 and 2024. His perseverance despite his broken jaw made him a fan favorite for 2025 and allowed him to finally cinch the Fat Bear Week crown.
Fat Bear Week has been so popular that it spawned a second contest among the adolescent bears of Katmai National Park in which cubs or yearling bears are pitted against one another to see who will win Fat Bear Junior (National Park Service).
For the past several years scientists have used laser scanning; a technology usually used to measure buildings and topographical features, to more accurately estimate the bears’ weight without needing to capture the bear (Popular Science). Since Fat Bear Week is not a scientific endeavor, but rather a celebration of the natural resources that must be protected; the estimations provided with the laser scanner are a much more feasible and less invasive option than traditional methods. As the technique is refined it is possible that this tool “could change the way biologists measure bear weight, which is crucial to determining a population’s health” (Popular Science).
Fat Bear Season coincides with the yearly salmon run, bringing with it an explosion of life as the salmon make their final trip to the headwaters where they were spawned. Salmon are a keystone species that bring a much needed boost of nutrients to ecosystems before winter sets in; allowing many species to prepare for a time when resources are scarce (PacificWild.org). One of the many species that depends on the yearly salmon run is the brown bear, or grizzly, which has to pack on the pounds before digging their den for the cold Alaska winters. During this rest period, called torpor, bears reduce their circulation to slow both their heart rate and breathing while remaining in a state that allows them to defend their den if necessary (fourpawsusa.org). Torpor can last up three months, during which time the bears eat nothing and can lose up to a third of their body weight.
Fat Bear Season officially kicked off on June 23 this year when explore.org launched their live feed allowing excited viewers to watch the bears feast on salmon at eight prime fishing spots along the Brooks River.
During years when salmon is abundant viewers are able to watch the bears play and enjoy their time in the river; while during leaner times the bears tend towards aggression as they fight to gain enough weight to sustain them over the winter. The official dates of Fat Bear Week 2026 have not yet been announced, now is the time to tune into the bear cams to get to know the bears ahead of what is sure to be a fierce competition amongst some of the largest brown bears on the planet.
You can learn more about the brown bears of Katmai Conservancy at their website katmaiconservancy.org, where you can also purchase official Fat Bear Week merch that helps raise money to protect the wildlife and wild places of Katmai National Park.
The Katmai Conservancy acknowledges that Katmai National Park and Preserve lies within the homelands of Sugpiaq/Alutiiq, Dena’ina Athabascan, and Yupik people. They honor and respect the diverse Indigenous peoples and cultures of this region and their ties to the land and wildlife, and are grateful for their continued stewardship since time immemorial.
Sources and Further Reading:
Katmai’s Brown Bears. Katmai Conservancy. katmaiconservancy.org. n.d.
The Brown Bear: Torpor or Hibernation? How bears doze through the cold season – eating nothing for up to three months. Four Paws USA. fourpawsusa.org. Oct 14, 2022.
Salmon: A Foundational Species. Pacific Wild. pacificwild.org. n.d.
Fat Bear Week: Past and Present. The National Park Service. nps.gov. n.d.
How scientists try to weigh some of the fattest bears on Earth: The Alaskan ursine of “Fat Bear Week” are very heavy indeed. Laser scanning can help measure their size. Maria Paula Rubiano. Popular Science. popsci.org. Oct 2, 2020.
Leave a Reply