Image source, NPS/ C SpencerImage caption, 480 Otis on the hunt for sockeye salmon in Brooks River

Polls have closed in Alaska's Katmai National Park and Preserve, and the fattest bear of the year is… 480 Otis, a three-time champion of chonk.

A dozen of the largest brown bears on Earth faced off during Fat Bear Week, an annual battle of bulk that rewards their pre-winter-hibernation gains.

Otis, who won in 2014, 2016 and 2017, was neither the biggest nor the youngest in this year's competition.

But the grizzled veteran easily prevailed over other beefy behemoths.

On Fat Bear Tuesday, the final round of the weeklong contest, the plump pro soundly defeated 151 Walker by over 6,000 votes.

Park officials had estimated Walker's weight to be in excess of 1,000lbs (71st), but by dint of his salmon-catching prowess, Otis transformed his physique over the late summer and early fall to win over an adoring public yet again.

Image source, NPSImage caption, The transformation of 480 Otis

The bears of Katmai are skinny over the summer, but ahead of the winter months, they make their way down to Brooks River, which runs through the park, and gorge on one of the largest and healthiest runs of sockeye salmon in the world.

The fatter they grow, the more fat stores they can subsist on in their winter dens and the healthier they will be once hibernation ends.

Brown bears can gain up to four pounds of weight a day and adult males can weigh up to 1,200lbs (86st).

Staff and photographers inside the park document the transformations of the furry residents for the online tournament, which champions Katmai's conservation efforts.

Nearly 800,000 votes were cast this year before Otis was crowned.

"The portly patriarch of paunch persevered to pulverise the Baron of Beardonkadonk in the final match," the park announced on Twitter, adding that the champ was "still chowing down".

For the first time this year, four baby bears faced off in a warm-up contest last month to crown Fat Bear Jr.

A freshman – 132's Spring Cub – topped the other chubby cherubs to win his first championship.

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