The strange story of the white-naped crane that fell in love with her keeper

Walnut the white-naped crane isn’t like all the other girls. She and Chris Crowe, her beloved zookeeper with the avian-inspired name (we really can’t make this up!) have been domestic partners for 14 years and they’re still going strong

Walnut is rumored to have killed not one, but two male crane suitors in the past.

“That’s the story that came with her,” Crowe says, “but we haven’t been able to confirm it. We definitely know other [zoos] have tried to pair her, and when we got her, we were told she killed two males who they tried to put with her, and the reason she was sent here is because we can do artificial insemination — but also because we can keep her separate from other cranes. She can see them, but she can’t actually fight with them.”

Like many birds, cranes mate for life, and Walnut — thought to have initially imprinted upon a human who hand-raised her as chick— has fallen hard for the soft-spoken zookeeper who was hired over a decade ago by the Smithsonian to care for her (and other zoo birds). And, according to research, birds who fall in love usually have more reproductive success. The pair’s differences might seem to initially inhibit baby-making, but read on before you pass judgment.

“We both came here the same year, 2004,” says Crowe. “She was here a month before I was. I was assigned to be the primary crane keeper, five out of every seven days … I would take care of her every day, five days a week.” His prior work experience with whooping cranes helped him get the position, but according to Crowe, Walnut took a while to warm up to him.

“She did not like me right away. She was fairly territorial and [made] a lot of threat displays. She probably pecked at my foot and leg a few times initially, but she was a lot more approachable than all the other cranes,” explains Crowe. “All the other ones would step back and be a little more wary, whereas she would come right up to me. Over time — partly because I took care of her, and partly because she had imprinted on people in the past, she kind of just stuck with me and gradually became more comfortable with me being around in her pen and taking care of her.”

Eventually, Walnut stopped acting territorial and quit threatening Crowe, but he still couldn’t get too close to her — maybe only within a few feet.

“It took a while before I could train her to stand still and let me do the artificial insemination technique,” says Crowe. Yes, you read that right: the 42-year-old zookeeper has helped to facilitate the birth of seven chicks with the 37-year-old endangered bird.

Smithsonian rep Devin Murphy says Crowe has “done really great work with Walnut, getting her to reproduce.” Cranes are one of the most endangered bird species. Eleven of the 15 species are endangered, primarily due to wetland habitat loss but also poaching. This decline affects white neck cranes in Asia, as well as whooping cranes in the U.S.

Walnut is originally from Asia. Her parents were illegally caught in China, but were saved and sent to the International Crane Foundation in Wisconsin. She hatched there. Fast forward to now — after producing several chicks, Walnut is not recommended to breed anymore (unless something happens to the crane population currently living in North American zoos), but her human mate has mastered the art of interspecies wooing.

“When she started warming up to me, she would do some of the crane courtship [rituals] which involve running around with the wings flapping, bobbing her head, jumping up and down, flapping her wings, and picking up crumbs or grass or flowers and tossing them in the air and catching them,” recalls Crowe. “When I recognized what she was doing, I did my best to imitate it. If I saw her bobbing her head, I started bobbing my head. If she was flapping her wings at me, I’d flap my arms as if they were wings. I’m sure I wasn’t doing it right for her, but she compromised, or put up with it, and it seemed to help us bond.”

After this courtship phase, Crowe eventually moved on to his artificial insemination efforts, which have helped to increase the endangered crane population. Plus, Walnut is a lot less lonely.

“She was hand-raised by people at another zoo in the early ’80s, and cranes are one of the bird species that will imprint and bond with whatever species is raising them,” he tells PEOPLE. “So, she did all the crane behaviors, acted like a crane, called like a crane, did all the displays and vocalizations of a crane, but she didn’t really recognize herself as a crane. I think she’s stuck in between; she relates more to people.”

Personality or disposition-wise, Crowe describes Walnut as “normally very happy, very exuberant. She dances a lot, calls a lot she’s very curious and alert. She knows everything that’s going on, what’s going on with people or looking up in the sky, seeing an eagle or vulture way up high.” Walnut also keeps herself busy in the yard and nearby stream, typically foraging for crayfish and worms, or the occasional mouse. Crowe says she is “very bold” and will walk right up to people, even though she’s only friendly to him and very unfriendly to everyone else!

Although Crowe and Walnut have a strong social bond, that isn’t the case with most humans. “We get along really well, she’s always happy to see me,” Crowe says, but “she’s not happy to see the other keepers, they normally don’t go in the pen with her. We have a sign up on the door, ‘Caution: Aggressive Crane’ to remind people. But she’s very tolerant of me. I helped her build her nest. I can pick up her eggs and she just stands there.”

As Walnut’s designated mate, Crowe is more than just a caretaker, he’s also a life partner. As mentioned, he helps her build her nest — and even watches her eggs.

“But we don’t want to leave her eggs with her,” he explains, “because we need both a male and female to incubate it. I don’t want to just take the eggs away, because it could be somewhat traumatic for her, but also then she would just recycle in two weeks and lay more eggs. And we don’t want her to just lay egg after egg, it wouldn’t be healthy for her. So, we have to give her replacement eggs that she can sit on … We give other cranes a wooden dummy egg, but she recognizes that as fake and kicks it out of the nest, so we use a real crane egg that’s infertile from years past. We drained out the yolk and filled it with plaster, so she has a real-looking egg. She doesn’t sit on it 24/7, she gets breaks; and if it’s hot or raining, she gets more breaks. I’ll go and stand by the nest and give her breaks, and she seems to know what that means. As long as I’m there, she feels safe walking away from it.”