The Bodacious Bears Are Back For Fat Bear Week 2021


Rachael Funnell

Digital Content Producer

clockSep 29 2021, 14:43 UTC
Fat Bear Week

I don't think you're ready for these jellies. Image credit: Oksana Perkins /

Few things in life can be relied upon, but that the bears of Katmai National Park and Preserve, Alaska, will bulk up with aplomb come October is one annual glimmer of routine we can all hold onto. Fat Bear Week is upon us for 2021, and as the roster of potential winners has demonstrated, it’s just as chunky as ever.

In case you’re unfamiliar with this momentous occasion, Fat Bear Week seeks to celebrate the fruits of Katmai’s resident bears’ labor as their summer of gorging results in a near-sphere-like physique come autumn. Before anyone has a chance to chime in with their unsolicited opinions about bear BMI, the annual Fattening is a life-saving transformation in a brown bear’s life as it prepares them for the season ahead.


During the summer months, brown bears can gain around 1.8 kilograms (4 pounds) a day as they enter hyperphagia, essentially an eating marathon with a goal to establish a hefty store of fat. The expanding-waist-race is helped along by the Katmai’s bountiful annual salmon run which saw a record number of fish pass through in 2020. While not the fattiest of the salmon species (king salmon takes the crown here), the sockeye is a suitable snack for trying to load up on fat, and given they whizz through in their millions, it’s easy to see how the annual feast yields such cuddly results.


Once primed and plump, the bears will step down from salmon fishing for a six-month sleep, during which time they can lose around a third of their total body mass. Surviving hibernation isn’t a guarantee and so heading into your nap with bulk to spare can be pivotal if a bear's to re-emerge the following spring.

As such, bodacious bears are a cause for celebration and thankfully Katmai’s 2021 Fat Bear Week Competition shows great promise for this year’s contestants. Of particular note are 435 Holly and 747 who won the 2019 and 2020 competitions, respectively, and show no signs of slimming down as the 2021 contest kicks off. 128 Grazer and 131 have also been turning heads among the IFLScience staff with blonde hair to rival even that of a pizzly bear. You can see all the bears in their portly glory here.


2021 also brought with it competition anew, as for the first time a junior contest kicked off pitting the park’s baby bears against one another. 132's Spring Cub came in first, earning them a promotion to the adult competition.


Voting opens at 9 am (PT) on September 29, so be sure to keep up with the results as they unfold and vote for your favorite! May the odds be ever in your fat bear.

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