Brown bears feast when summer turns fall — who is the fattest of them all?

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Bear 747, a large adult male, is in the running for fattest bear. (L. Law/National Park Service)
Bear 747, a large adult male, is in the running for fattest bear. (L. Law/National Park Service)

It’s officially fall — a wonderful time of year when brown bears in Alaska get ridiculously fat feasting on salmon.

People on social media go wild for these bulky bears during Fat Bear Week.

Since 2014, the annual competition lets the public decide which bear to crown the fattest at Katmai National Park. Last year, eager fans cast more than 600,000 votes online.

Mike Fitz, founder of Fat Bear Week and naturalist for, is a former Katmai park ranger. Seven years ago in the visitor center, he and some other rangers saw a webcam viewer showing a side-by-side image of a bear in the early summer compared to the late summer.

Grazer before and after (Photos by N. Boak and L. Law)
Grazer before and after (Photos by N. Boak and L. Law)

The stark difference in the photos sparked an idea: match up before and after photos of bears as a competition to see which bear was the fattest, he says.

The one-day Facebook tournament bracket contest that was quickly thrown together has now evolved into a week-long competition.

Many won’t even get the chance to witness these omnivores fishing for food along the Brooks River in Katmai National Park. The habitat there is ideal for hungry bears to devour salmon for long periods of time.

“I know of no other place in North America, or perhaps no other place in the world, where bears can fish for salmon for months at a time,” he says. “... It’s a good time to be a bear.”

Scientists at the University of Alaska in Fairbanks found that in Alaska, four of the five species of salmon — a staple in bears’ diets — have declined.

Fortunately, Fitz says the bears in Katmai will “probably be OK” because of their resiliency in the face of change.

Chunk before and after. (Photos by N. Boak and L. Law)
Chunk before and after. (Photos by N. Boak and L. Law)

Plus, he says the Bristol Bay run of sockeye salmon is “sort of a beacon of hope right now because it is doing extremely well and the bears are benefiting from that.”

These bears don’t play around when stocking up for hibernation: The largest bears at Katmai are estimated to be between 1,200 to 1,400 pounds, Fitz says.

The animals aren’t weighed by park rangers, so it’s hard to judge their exact body fat percentage, he explains. Last year’s Fat Bear Week champion, 747, was an estimated 1,400 pounds.

To put that incredible weight gain into perspective: Cubs at birth are about 1 pound and equal to the size of a soup can, he says.

Grazer, a plump new mom to two yearling cubs, is among the fan favorites this year. The extremely defensive mother bear gets ferocious if another bear even wanders near her family’s vicinity, Fitz says.

Chunk, an “extremely hefty” male bear, is notable for the scars across his dark brown fur and his “big butt” for which he received his nickname, he says. Chunk has been chubby since his young cub days, he says.


Otis, a portly older adult male with one floppy ear, is another high-profile contender. He boasts a long list of accomplishments: Otis was the inaugural Fat Bear Tuesday winner in 2014 and twice crowned Fat Bear Week champion.

Fitz says Otis, a “charismatic bear,” faces different challenges than the younger bears because of his age — but that has fans rooting even harder for him.

Otis before and after. (Photos by N. Boak and C. Spencer)
Otis before and after. (Photos by N. Boak and C. Spencer)

Participants really get into the competition. Some launched social media campaigns for their favorite bears while others committed to eating salmon dinners and drinking honey beer for an entire week in celebration. Fitz says he never expected the idea to take off like it has and is happy to see how much joy it’s brought people across the world.

He’s also pleased to see Fat Bear Week serve as an educational tool for humans to better understand bears, their ecosystems and modes of survival.

The Fat Bear Week winner doesn’t get a salmon feast handed to them or a belly rub, but Fitz says they do get worldwide recognition for their impressive heft.

Voting is open until Oct. 5. May the fattest bear win!

Ciku Theuri produced and edited this interview for broadcast with Todd MundtSerena McMahon adapted it for the web

This segment aired on October 1, 2021.


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Peter O'Dowd Senior Editor, Here & Now
Peter O’Dowd has a hand in most parts of Here & Now — producing and overseeing segments, reporting stories and occasionally filling in as host. He came to Boston from KJZZ in Phoenix.


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Serena McMahon Digital Producer
Serena McMahon was a digital producer for Here & Now.



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