Thousands of fish are ripped to shreds along the Brooks River each July.
With a glut of fresh salmon at their disposal, many brown bears just munch the fatty skin and brains of the fish, leaving the bright red meat for lesser bears.
By later July, once the salmon run peters out, however, most of the bears usually vanish into the dense woods from whence they came, seeking fresher feeding grounds.
But it’s August 1, and Katmai National Park’s Brooks River — home to explore.org‘s five live-streaming webcams — is still bustling with brown bear activity.
The reason for this prolonged fishing season is simple: The famous river is still teeming with sockeye salmon thanks to an exceptional salmon run, specifically from Alaska’s Bristol Bay this year.
“We’re probably going to see the second-highest return since 1963,” Curry Cunningham, a Bristol Bay fisheries expert and quantitative ecologist, said in an interview.
The specific major waterway that eventually feeds into the bear-rich Brooks River is the Naknek River, whose 2018 run of 2.2 million salmon was described as “good and plentiful,” Cunningham said, though some other Alaskan rivers saw big fish records broken.
Once salmon make their way up the Brooks River, the fish amass beneath the waterfall as they attempt to leap over the falls.
Though not a perfect scientific indicator of the strength of the overall salmon run, park rangers count the number of fish leaping beneath the waterfall as an indication salmon numbers. And as the bear cams show, there are bounties of fish still attempting the jump.
So the bears, hellbent on getting fat ahead of hibernation, are sticking around. And it seems to be working.
Some of the most visible bear cam bears have fattened up, long before the onset of winter.
“The bears at Brooks River are well-endowed for this time of the year,” former Katmai ranger Mike Fitz, an expert naturalist who is reporting on bear activity for explore.org this season, said via email. “Several bears — 747, 128, 409 — look like they are fat enough to start hibernation already.”
This summer is the first time the Naknek River broke over 2 million fish since it just missed the mark a decade ago, in 2008.
Salmon runs are highly variable each year — so it’s difficult to say for certain if any massive run means an extended salmon run at the Brooks River.
Not much is known about the little-seen lives of salmon as they travel through deep interconnecting rivers and lakes, en route to places like the Brooks River. The journey is generally believed to take a couple weeks.
“That period in that lake, we know very little,” noted Cunningham.
The hungry predators awaiting salmon near the Brooks waterfall surely isn’t a welcome end for the fish, who planned to lay eggs in their spawning grounds farther up river. But the still-vibrant run is hugely valuable for the bears, who endeavor to get as fat as possible before the long-winter famine hits.
In fact, Katmai National Park holds a “Fat Bear Week” competition in the fall each year, before the bears retreat into hibernation. And with the bear cam bears filling out already, the competition promises to be stiff.
“Fat Bear Week is going to be intense this year,” said Fitz.