It's Fat Bear Week in Alaska's Katmai National Park - time to fill out your bracket

Who doesn't love big fat bears? At least from a distance. And, who doesn't love filling out a bracket, where winners move on and losers go home?

Combine the two and you've got Fat Bear Week — a kind of ursine March Madness, in October.

There are an estimated 2,000 bears in Katmai National Park & Preserve, a glorious and massive 4.4-million acre stretch of wilderness in Southwest Alaska. Each year the bears spend the summer trying to get as fat as they can to prepare for hibernation.

And in October, bear fans get to vote on who is the fattest of them all.

This year, the bears were whittled down to a bracket of 12 contenders. Four heavyweights had first-round byes. Voters on the park's Facebook page choose their favorite from each match-up. The winner moves on to the next round.

As the competition began last week, Katmai Conservancy media ranger Naomi Boak had her eye on two of what she calls "favorites." There’s Number 435 (they assign a number after monitoring the bears for a while)... and number 747. He is "as big as a jumbo jet," she says.

"He was so big he looked like he was ready to hibernate in July. He's the size of two bears."

This isn't fat-shaming, Boak says. It is fat-glorifying, as the biggest bear has done the best job getting ready.

"They lose a third of their body fat over the winter," Boak says. "So they need all that fat to survive."

Skinny to fat

The Fat Bear Week competitors are coastal brown bears who forage along the Brooks River. They dine voraciously on one of the largest sockeye salmon runs in the world. There's a fascinating science to this annual gorging, Boak says. A hormone that usually inhibits hunger switches off in the bears this time of year.

Boak and her fellow media ranger, Brooklyn White, chose the 2019 competitors — a variety of bears including males, females and so-called sub-adults. Those are emancipated cubs that have grown up and spent a year on their own.

Boak and White wanted good before-and-after photos of the 12, showing skinny shots from earlier in the year and recent fat ones after feasting. Kind of a reverse infomercial.

White says they also wanted bears that people outside the park had gotten to know after watching them on remote bear cams along the Brooks River.

"Many of those folks who, you know, [who'd spent] time watching the cams, would already have a relationship with a bear they were seeing in the contest," she says.

Don't cross a line

The bear cams and 5-year-old Fat Bear Week contest are helping people connect with what goes on inside the park, and helping extend the park's conservation mission. According to Boak, last year there were nearly 56,000 votes for Fat Bear Week. This year, the park hit that number in the first two days.

Obviously, people like fat bears.

But there's a line that park officials don't like to cross. They try not to anthropomorphize wild animals in a wild place. That's why they give the bears numbers — although bear cam followers like to add names. Like Lefty, Chunk and Grazer from this year's contest. Or last year's champ, Beadnose, No. 409. Boak says Beadnose is known worldwide, but this year, the bear's not defending her title.

"She was a no-show," Boak says, but doesn't know why.

Beadnose could've been injured, could've died, or gone to another part of the park to fish.

Whatever happened, Boak acknowledges that Beadnose went out on top.

"She went out in a big way," Boak says, unable to resist one more fat bear pun.

This week, on Fat Bear Tuesday, a new champion will be crowned. The first prize, says Brooklyn White, is, she hopes, a successful hibernation.

And, a lot of new fans.

Copyright 2019 NPR. To see more, visit https://www.npr.org.

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