【Sisters Slave (2019)】

One should tread carefully around bear 856.

He's one of the most dominant fat bears of Katmai National Park and Sisters Slave (2019)Preserve ⁠— which houses a population of internet-famous Alaskan bears livestreamed on explore.org — and his aggression and size earns him access to the best fishing spots. For much of the last decade, bear 856 sat atop the fat bear hierarchy in the park's salmon-rich Brooks River, and he remains a top contender.

It's not wise to impede upon 856's fishing territory, which is closely guarded bear real estate. An encroaching bear risks a fight, injury, or at minimum, being run off. But this didn't stop two enterprising subadult, or teenage, bears from successfully stealing a fresh 4,500-calorie sockeye salmon from bear 856, live on the bear cams this week.

You can watch the action in the clip below:

• Bear 856, an expert at catching fish beneath the Brooks River waterfall, snags a fish and returns to shallower water to chow down.

• A young bear approaches 856, prompting 856 to drop the fish and chase the insolent intruder away.

• Meanwhile, another young bear furtively snags the fish and flees with the bounty. Bear 856 returns, his meal gone.

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This episode, while entertaining, underscores the intense competition bears endure during the summer and fall. They are competing for calories. They must fatten up before their long winter hibernation, wherein they subsist entirely off their fat stores. A bear with ample fat has better odds of surviving the brutal Alaskan winter, and also of awaking with enough energy to yet again seek out nutrients.

That's why a fat bear is a successful bear.

Bear 856, with his profound aggression, had dominion over all the other bears feeding at the Brooks River, even those bigger than him, for much of the past decade. Bears would at times flee from 856 when he appeared at the river.

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But last year, the behemoth bear 747 overtook 856 as the river's most dominant animal. It wasn't a violent fight. (Brown bears usually intimidate with bold posturing, as opposed to brawling and potentially hurting themselves.) Beneath the iconic Brooks waterfall, bear 747 approached bear 856 and intimidated him, ultimately displacing 856 from a prime fishing spot in the river.

Still, bear 856 stands as a titan among some of the most successful wild bears in Katmai. Just, sometimes, young whippersnappers might find a way to steal his fish. No worry, bear 856 will catch hundreds more salmon this summer. He always does.