15/09/2026
In July 2007, brown bear 420 arrived at Brooks Falls in Katmai National Park severely injured, with a broken jaw and large open wounds on both sides of his body. For a wild brown bear at Brooks Falls, July is a critical time. The goal is simple: catch as many salmon as possible, eat enough, and build the fat reserves needed to survive roughly five months of hibernation.
For a healthy bear, eating a salmon is relatively easy. It can grab the fish, crush through the spine, tear the flesh apart, and swallow the pieces quickly. But with a broken jaw, every fish becomes a difficult challenge.
The salmon at Brooks Falls can weigh between six and ten pounds and struggle fiercely when caught. A bear needs a powerful bite, strong teeth, and enough jaw movement to tear and chew the meat. For 420, an unknown fracture in his mandible made all of those movements painful and difficult.
Before his injury, 420—known to the National Park Service by the field nickname “Genghis”—was one of the more dominant bears at Brooks Falls. He was known for taking fish from smaller bears and forcing competitors away from some of the best fishing spots near the falls and the pool below.
But after arriving injured in 2007, everything changed.
He stopped challenging larger bears and no longer stole their fish. His size was still enough to discourage smaller bears from confronting him, but he could no longer rely on aggression to maintain his position. He had become a bear that was still powerful enough to hold a fishing spot, but too injured to fight for one.
Instead, 420 adapted.
He continued fishing and carefully ate his salmon using the uninjured side of his mouth. According to the National Park Service, this careful chewing allowed him to maintain his weight and body size despite his serious injury.
No veterinary treatment was given. Under Katmai's Bear-Human Conflict Management Plan, naturally injured bears are not tranquilized for veterinary care. Rangers and biologists could only observe and document 420's condition throughout the summer. His survival depended on whether he could consume enough salmon to build the fat reserves necessary to endure the coming winter.
Then came the most difficult part.
From November 2007 through the following spring, 420 disappeared into his den, where no one could see how his broken jaw was healing. Remarkably, research on hibernating grizzly bears has shown that they can maintain their bone density and skeletal strength during months of inactivity. For 420, this meant his injured jaw was healing inside a body capable of preserving its skeletal integrity throughout hibernation.
He survived.
When 420 returned after winter, his jaw had healed and his wounds had closed. By the 2009 and 2010 seasons, he had once again become one of the dominant bears at Brooks Falls.
The bear that had been forced to retreat from fights, carefully chew his food, and give up his position in the hierarchy had eventually returned to the top.
Brown bear 420's story is a remarkable example of survival, adaptation, and resilience in the wild.
Image is for illustration purposes only.
Source: Michael Fitz, National Park Service, Katmai National Park and Preserve, “The Resilient Bear,” July 14, 2013.
