"It was literally like stepping into a Dr. Seuss story," Douglas said. "The birds would come down and have this citrus smell and they're landing on the rocks all around you and they have these elaborate social interactions. It was pretty peculiar, the first time it happened."
He noticed the birds had little trouble with ticks compared to other species of auklets and seabirds.
The citrus smell reminded him of a research paper he'd read about birds that rubbed citrus peels in their feathers to help ward off pests, which at best are nuisances and at worst carry disease.
It wasn't until years later, however, when he was studying auklets on St. Lawrence Island in the Bering Sea where mosquitoes are more prevalent that he began to see the compound's effect on the airborne pests.
To test his theory, he went into the laboratory with a few auklet feathers. An analysis showed him the chemicals that make up the auklet's "odorant." Most are available commercially.