For years, he collected stuffed and mounted animals and kept them in his attic until he finally got his own building in Frederic, where he founded his dream museum and called it the Underground Forest. A few years later, however, the completion of I-75 to Mackinaw City diverted traffic from the little town and drained it of tourists.
Not long after, he moved his museum to Gaylord, right beside the new high-traffic freeway, and reopened it in 1965 as the Call of the Wild.
His three children took over the family business after Johnson died in 1973. Vollmer is usually the one behind the counter in the gift shop, day after day. Summer is the busy season, she said, while on some days in the winter it's often just her and the animals.
In an era when the attractions at the edges of most exit ramps are usually gas stations, big-box stores and fast-food chains, the Call of the Wild is a charming throwback to the era of unique roadside offerings that reflected the place where they sprang up.
"I know we're old-fashioned," Vollmer said. "It's family-friendly and very child-friendly, and that's one of our assets."
Vollmer's daughter Morgan Vollmer, 32, who has worked at the museum for 18 years, said kids love it.
"We see some kids three times a week," she said. "Parents will actually avoid our street in order to avoid coming here because as soon as they see it, kids want to go here again."
The exhibits are low-tech and uncomplicated. The backdrops were hand-painted years ago by local artists and depict Michigan landscapes with rolling hills, white pines, sunlit fields or snow-coated forests.
The foregrounds contain shredded Styrofoam to represent snow, dried moss to hint at grassy plains and withered leaves to suggest a passing autumn. A few sentences on backlit panels next to the exhibits offer information detailing the animals' habits and habitats.