The crane who fell in love with a human
The world population of white-naped cranes is falling fast, said Sadie Dingfelder. To get one to breed in captivity, a human handler had to seduce her.
E ARLY ONE SUMMER morning, as rain is misting the foothills of the Blue Ridge Mountains, a middle-aged man is courting a crane. Chris Crowe, 42, bends forward in a slight bow and then flaps his arms slowly, like wings. “Hey, girl, whatcha think,” he coos. Walnut has heard that line before. The stately bird ignores Crowe, reshuffles her storm cloud–gray wings, and snakes her head gracefully to the ground, looking for something tasty to eat. “Come on, now,” Crowe says. The zookeeper grabs a fistful of grass and tosses it into the air. This is Crowe’s sexiest move— a sly reference to building a nest together. Walnut looks up, curiosity glinting in her marigold eyes, but then she returns to probing the soft, wet ground with her barkcolored bill. “Try getting in the van,” Crowe calls to me. I follow his suggestion, and almost immediately, Walnut starts responding to Crowe’s overtures. She returns his bows and then turns away from him and holds her wings loosely away from her body. Kneeling behind the bird, Crowe rests a hand gently on her back. Then he starts rubbing her thighs, rhythmically, almost pornographically. Thirty seconds elapse before Walnut steps away from Crowe, fixes a few out-ofplace feathers, and then stretches out her wings, asking for another go-round. In past years, Crowe would have taken this opportunity to inject Walnut with a syringe of crane semen. Alas, a matchmaker in Memphis—the keeper of the white-naped crane studbook, whose job is to ensure a genetically diverse captive population—has decreed that they don’t need any more babies from Walnut, at least not this year. But that doesn’t stop Crowe and Walnut from going through the motions all summer long, five days a week, sometimes several times a day. “It’s not exactly fun for me, but it keeps Walnut happy,” Crowe says. More to the point, this strange cross-species seduction has helped ensure that whitenaped cranes continue to exist. W ALNUT ARRIVED AT the Smithsonian Conservation Biology Institute (SCBI), an endangered-species breeding center in Front Royal, Va., back in 2004. She was the most genetically valuable white-naped crane in captivity. At 23, she had yet to produce a single chick, and she had a reputation for murdering her mates. Two male cranes that made amorous overtures toward Walnut had been found dead, with their bellies sliced open by her sharp claws. That, at least, was the rumor. Walnut hatched on July 2, 1981, in an old horse barn at the International Crane Foundation (ICF) in Baraboo, Wis. Her parents, Mercury and Amazon, were wildcaught birds. Captured illegally in China and smuggled to Hong Kong, the two cranes were probably en route to a private menagerie, or perhaps a taxidermist. Instead, they were intercepted by local authorities and eventually shipped to the ICF. This kind of poaching is less common today, but the white-naped crane population is falling because of a more relentless foe: booming human populations overtaking, polluting, or draining the wetlands the birds need to survive. In addition to demanding as much as several hundred acres of wilderness for a single pair of cranes, these difficult birds seem drawn to marginal places. For instance, one of the white-naped cranes’ most important wintering grounds is the 2.5-mile-wide demilitarized zone between North and South Korea. As conservationists work to persuade people to preserve land for cranes, zoos are pursuing a parallel strategy. They are breeding captive white-naped cranes, creating an “insurance population” ready to be reintroduced should their wild counterparts disappear. But the problem with captive populations of animals is that they tend to get inbred, which is why—in 1981—keepers were thrilled to have the genes of Mercury and Amazon to add to the mix. The two wowed ICF staff with their exuberant courtship displays—running, bowing, leaping, and trumpeting their love for each other all summer long. That year, they produced nine chicks, including Walnut. These wobbly baby birds were raised in small herds, minded by so-called chick mamas who fed them, cleaned their pens, and took them out to a horse ring for daily exercise and to a baby pool for swimming lessons. The chick mamas were mostly volunteers, says Joan Fordham, a former ICF employee. Fordham’s 10-year-old daughter was a chick mama one summer, and she apparently didn’t get a lot of training. “If the cranes started fighting, she knew how to separate them, and that was pretty much it,” Fordham recalls. The danger of hand-rearing crane chicks, however, is the possibility that they may “imprint” on humans. When it’s time to find a suitable mate, some human-imprinted cranes seek out a partner that looks like their presumed parent—a human, instead