Few animals capture our imaginations like the great brown and grizzly bears of North America. These gigantic predators inspire wonder, respect, and fear in the hearts of Outsiders across the globe.
Yet there’s a lot of confusion for the public over the true difference between a brown bear and a grizzly bear. The answer can get quite muddled, too, even for experts in the field. Thankfully, Outsider was able to sit down with one of the most knowledgeable bear experts out there – Katmai National Park & Preserve’s Ranger Cheryl Spencer – to clear the fuzz once and for all.
While chatting with Ranger Cheryl on all things Fat Bear Week, we wanted to know: What is the definitive answer to this popular question? How would you differentiate browns from grizzlies for someone looking to know more about the species as a whole?
“We get asked this question all the time, because it is confusing!” Cheryl begins for our National Parks Journal. “To keep it simple, though, they are technically the same species.”
But wait, the answer can’t be that simple, can it? Spoiler alert – it’s not!
There is, however, one key fact to remember: “All grizzly bears are brown bears,” Ranger Spencer explains. “Grizzlies are simply a sub-species of brown bear. So they’re all Ursa arctos.”
The Definitive Difference Between Brown and Grizzly Bears
As the Katmai National Park Ranger and self-professed “bear-nut” explains, “The difference is basically where the bear lives.”
“Grizzly bears are brown bears that live in interior lands,” Cheryl continues. “Whether that’s Alaska or other places, grizzlies don’t have access to coastal resources. They live inland.”
Where as brown bears, like the behemoth bruins of Fat Bear Week, “have access to these coastal resources.” This includes Brooks River’s incredible salmon run that feeds Katmai’s fat bears.
“All the Katmai bears are brown bears,” Ranger Cheryl offers, “because we live near the coast and they all eat lots of fish through our coastal resources.”
As for grizzly bears, she adds that a good way to think of this sub-species separate from browns is to think of the famous bears of Yellowstone National Park. They are 100% grizzlies.
Fascinatingly, Cheryl notes that “brown bears tend to be larger than grizzly bears.” Grizzlies, however, “tend to be far more territorial. They inhabit a much larger bear bubble in places like Yellowstone.”
Both their differences in size and territorial nature boil down to grizzlies having much less food to eat where they live. While grizzly bears fight fiercely to protect limited resources, brown bears are able to grow fat, happy, and larger due to the abundance of food coastal regions offer.
The Lives of Katmai National Park’s Brown Bears
Few events make this clearer than Fat Bear Week, too. Alaska’s Brooks River saw a “record-breaking” number of escapement fish this year, Ranger Cheryl cites (escapement being the total number of adult fish returning to a hatchery or stream to spawn).
The salmon’s unparalleled escapement was late. Very late, in fact. And Katmai’s brown bears were forced to concentrate on Brooks Falls if they were to catch any salmon at all. The result was a spectacle like any other for FBW 2021 – one that saw upwards of 50 bears fishing the same Brooks spots at the same time as Ranger Cheryl’s own remarkable photograph shows above.
Cheryl says that Katmai officials are still “not exactly sure why, but for whatever reason [2021’s] salmon run did not come up Katmai’s Brooks River the same time as it usually does. Bears are really smart and intuitive, and they know that early July is typically when the fish start showing up. But that wasn’t true for this year.”
But when it arrived, the brown bears – not grizzlies – of Katmai National Park had a venerable feast at their clawtips.