Vandergaw wades among the bears carrying only a stick for protection. He does not permit the use of deadly force. It is a risk Terry accepts when he follows Vandergaw with his camera, passing within arm's reach of grizzlies that can weigh more than half a ton.
Isolated here in the deep woods, Terry is honing the art of living dangerously. Every day is a learning curve of both survival and the unexpected intimacies of filming close to the great predators.
"I can't film if you put, now look, now you put slobber all over the lens," Terry said when a bear licked the camera lens.
There's even the occasional terrifying run-in at the outhouse, its door long ago ripped off by a marauding bear.
"Right in front of this doorway, here came a great big grizzly. She put her claw inside and grabbed hold of my boxers – and the boxers were attached to me! So I literally had to rip the boxers from her claws and try and push her off with a stick and make a hasty retreat," Terry recalled.
During the half-year shoot done for the Cable TV channel Animal Planet, Terry documented both the strange and the sublime.
There was the evening when a black bear wandered into Vandergaw's kitchen. "Of all the bars, you had to come into mine. Give me a kiss," said Vandergaw. "Come on, give me a kiss."
In another intimate moment, a mother grizzly lay near Vandergaw while nursing her cubs -- as the cameras rolled. "I can't believe it. She's laying down nursing right in front of me. It's amazing," Vandergaw said.
For Terry, having grown accustomed to the strange yet wondrous rhythms of Bear Haven, it has begun to feel like home.
"I'm either going mad, losing the plot, or I'm just becoming soft because this really makes me happy," Terry said.
But it also scared him.
Living and working together in the Alaskan bush, the bear enthusiast and the enthusiastic filmmaker have developed an extraordinary trust.
When a large grizzly emerges from the woods, Vandergaw gave directions on what to do that possibly saved Terry's life.
"No bites," Vandergaw commanded an approaching female grizzly.
"I'm feeling a little vulnerable, Charlie," said Terry as he continued to film the encounter.
"Just keep backing away from her," said Vandergaw.
It is a tense moment caught on film and a stark reminder of the constant threat posed by these creatures.
"Just to see someone get that close to the grizzlies and the black bears and all the confusion seems insane," Vandergaw said. "But it's like taking something out of context. I mean you have to see the whole thing. You have to understand the number of years of experience. Of course, saying all of that I can get chewed on tomorrow."
And that's what has experts like Sean Farley, a bear biologist for the Alaska Department of Fish and Game, so worried.
"It's a definite safety concern. One of these days, the bear will come back and not Charlie," said Farley.
Over many summers, Vandergaw has watched generations of bears come and go. He knows most by name, including Walt, a 500-pound creature who walks right into his kitchen.
"If I can control him in here and keep him from tearing things up then I'll let him in. He's been in here for years," Vandergaw said.
It is a surprising evolution of a man who began as a hunter, when this land was a hunter's paradise. Gradually, the hunter hung up his gun.