David de Muelles told ABC News today he stumbled upon the "beautiful moment" on Nov. 12 while leading a bus tour of the area. He said he had stopped the bus by a famous Eskimo dog sanctuary in the area when he spotted the bear.
"This big bear had just woken up from a cat nap and stopped right by the dog," de Muelles said. "The bear then just started gracefully petting the dog like a human."
He added, "It was incredible to see such a powerful animal be so friendly with such a small dog. Normally, these animals are known as killers."
The scene -- which de Muelles described as "heartwarming" and "absolutely beautiful" -- even brought one of the clients on the tour to tears.
"I was so happy to be able to get her to see such a crazy, once-in-a-lifetime thing," he said. "She was ecstatic."