Unbeknownst to the enormous bruins, some of them are also competing in Katmai National Park and Preserve’s Fat Bear Week, Alaska’s annual celebration of gluttony and nature’s abundance.

For seven days starting today, wildlife fans will submit online votes in a playoff-style competition among 12 of the park’s fattest brown bears photographed at the salmon-rich Brooks River. The winner will be announced on Oct. 5.

The week-long online extravaganza is a joint project of the park and two non-profit partners, the Katmai Conservancy and explore.org, a multimedia organisation that operates live nature cameras around the world, most famously its Katmai “bear cam.”

Fat Bear Week grew out of a single-day promotion in 2014 that was expanded to a full week the following year. It becomes more popular each year, with online voting growing to nearly 650,000 votes cast last year from 55,000 votes cast in 2018, said Naomi Boak, a Katmai media ranger.

The popularity is easy to understand: fat bears bring joy to people. “They get to do something and be healthy that we don’t get to do, and that is be fat,” she said.

There are Fat Bear T-shirts, coffee cups and other merchandise. There is Fat Bear school curriculum, with students tuning in to learn about biology, ecology and wildlife.

Katmai’s bears are among the biggest in the world, thanks to the abundant runs of salmon that swim into the river system from southwestern Alaska’s Bristol Bay. They number about 2,200, can grow to well over 450kg from summer feasting, and can also lose a third of their body weight during hibernation.

Salmon and survival

This year’s record Bristol Bay salmon return, which followed other recent years of big runs, has been a boon for Katmai’s youngest bears. “They benefited from being born in the time of plenty,” Boak said.

But even the older bears are looking extra-big, she said, citing as an example a 14-year-old named Walker. “He has not grown up, but he has certainly grown out,” she said.

The connection between Bristol Bay and the fish-fattened bears of Katmai is not lost on opponents of a proposal to build a massive copper and gold mine downstream from the park. The planned project, known as Pebble Mine, would threaten the survival of the salmon that sustains the park’s bruins, they say.

Fat Bear Week highlights some of the resources at stake, said Jim Adams, Alaska regional director of the National Parks Conservation Association.

“It can be a reminder that the bears depend on a healthy ecosystem and the world’s greatest salmon run,” he said.