Operation Migration relies exclusively on such hospitality. The organization, a nonprofit on an unforgiving $700,000 budget, gets almost no government money and so is left to scrape up the majority of its financing from individual donors. A cult of these so-called Craniacs now reads the crew’s daily journal religiously at OperationMigration.org, following the team and its numbered cranes like the cast of a reality show. (After Condie’s announcement, one woman explained to me that 827 is known for being “very independent.”) Along the route, well-wishers also bring the crew comfort food: very heavy hams, pots of chili. Already that morning, Condie was handed three batches of homemade fudge, several dozen donuts and a carrot cake. “Everybody puts on 10 pounds on migration,” she said later with a laugh. No one ever thinks to bring them a big salad.

The early-morning flyovers are the only opportunity for the Craniacs to even see the birds. The cranes must be moved from the refuge in Wisconsin to two refuges in Florida as furtively as fine art is moved between museums. From the time they land at each stopover to the time they can take off again, the cranes are stashed in a camouflage pen, tucked out of view and ringed by two electric fences. Costumed workers feed them twice a day, but otherwise the area is off-limits and resolutely guarded from trespassers, hunters, journalists and dogs. Martha (Operation Migration asked that I not disclose her full name) was sworn to secrecy, but it didn’t take. “This has been wonderful,” she loudly told acquaintances outside the chapel. “The best week of my life.”

Condie kept fielding questions from the crowd. “You only have to show the birds the way once,” she explained. After following the trikes their first year, the cranes continue migrating back and forth on their own each spring and fall. That very morning, in fact, graduates of the team’s seven previous ultralight-led migrations — 73 cranes in all — were scattered up and down the eastern flyway, at various points on their passage to Florida. Also scattered up and down the flyway were biologists — lots of biologists — from Operation Migration’s many partner organizations, tracking the radio signals emitted from those birds’ leg bands. And now that Operation Migration’s current class of cranes were airborne, its crew would hit the road, too, chasing the migration to its next stop in two motor homes, two pickups towing campers, and two vans, one towing a 50-foot supply trailer with a spare aircraft. All told, seven state and federal agencies and two nonprofits with an annual collective budget of $1.7 million in public and private funds were hard at work, fulfilling humankind’s responsibility to a bird that we’ve defibrillated out of near-certain extinction and gotten breathing again, if not yet absolutely saved.

The whooping crane, David S. Wilcove, a Princeton ecologist, told me recently, “is just about the most charismatic endangered species in America.” By 1941, only 21 wild ones remained. Today there are 381, enough to make it one of the most uplifting success stories in a field where the bar is admittedly sinking rather low. By now, one biologist told me, “work on any endangered species is certainly a very severe, rear-guard effort.” Twelve percent of the world’s bird species are threatened with extinction, according to the International Union for Conservation of Nature — so are a fifth of all mammals, and almost a third of all amphibians. In other words, we’ve backed ourselves into a corner, and sustaining the world’s wildlife will require progressively more systemic interventions from here on out. “Many of those species, probably most of them,” Wilcove said, “are in a certain sense wards of the state. Now and for the foreseeable future, they will be dependent on humans for their survival.”

Operation Migration exemplifies the kind of ingenious, unwavering work that needs to be done — and that we’ll need to keep doing, maybe forever, even as the strenuous administrative challenge of micromanaging so much of the natural world begins to blur the line between conservation and domestication. Already, it has come to this on planet Earth: men dressed like birds, teaching birds to fly.

3.

The hum of the trike engines swelled into a buzz. Then the lead pilot, Chris Gullikson, reappeared in the sky, drawing a lopsided V of tremendous white shapes behind his wingtips. As the parade of birds and machines coasted over the chapel and the three large wooden crosses driven into the ground beside it, people raised their binoculars and cameras to their faces and tilted back their heads. “It looks like a revival from up here, Liz,” a voice quipped in Condie’s radio. It was Jack Wrighter, one of the retired commercial pilots who flies top cover for the migration in his Cessna 172.

Image Sort-of-Feathered Friends Beverly Paulan (left) and Heather Ray, like all Operation Migration workers, wear crane suits when contact with the flock is even remotely possible. The birds are shielded from human interaction at all times. Credit... Mark Peterson/Redux, for The New York Times

“There’s not a biologist among us,” Joe Duff told me later. (There is, however, a metal sculptor, a former butterfly breeder and Gullikson, who splits the rest of his year between leading adventure tourists into tornadoes and designing English-style riding saddles.) Duff, who is now 59, was a photographer in Toronto when, in 1993, he helped another ultralight hobbyist and artist named William Lishman — the first person to fly with birds — lead 18 Canada geese on a migration from Ontario to Virginia. “The whole idea was to use this technique for endangered species,” Duff told me. Soon the two men started practicing by costume-rearing nonendangered sandhill cranes and then migrating with them.