Walnut, famous white-naped crane that chose a zookeeper as her mate, has died at 42 — rest in peace

The Smithsonian’s National Zoo is mourning the loss of one of their most unique and famous animals: Walnut, a white-naped crane that imprinted on humans and chose a zookeeper as her mate, has died at 42.

The news was announced in a press release by Smithsonian’s National Zoo and Conservation Biology Institute. At 42, Walnut was considered geriatric and had far surpassed the life expectancy of her species: white-naped cranes typically live about 15 years in human care.

Credit: Chris Crowe, Smithsonian’s National Zoo and Conservation Biology Institute

The white-naped crane is native to northeastern Mongolia and northeastern China, but Walnut’s parents were taken illegally out of their native land and brought to the US. Walnut was born in Wisconsin in 1981 and rescued by the International Crane Foundation.

As the offspring of two wild-caught cranes, Walnut was considered extremely genetically valuable, and the Association of Zoos and Aquariums’ Species Survival Plan made several breeding recommendations. However, Walnut had no interest in other cranes and would attack her partners.

Since Walnut was hand-raised by humans, she imprinted on her caretakers and was more interested in being with a human rather than a crane. After she arrived at NZCBI’s Virginia campus in 2004, bird keeper Chris Crowe gained her trust and Walnut chose him as her mate.

During mating season, Chris would go through the rituals with Walnut, including dancing, offering nesting materials and food — and finally impregnating her through artificial insemination, using sperm collected from a male of the species.

This unusual but heartwarming routine made Walnut a viral star. It also helped give a boost to this vulnerable species: between 2005 and 2020, Walnut successfully contributed eight offspring. (Her fertile eggs were given to other female cranes to raise as their own, to give them the best chance of survival.)

Chris and Walnut’s unusual courtship also helped give NZCBI’s bird team “valuable insights” about courtship displays, breeding behaviors and parenting.

“Walnut’s contributions to her species’ survival helped add to scientists’ knowledge about imprinting and artificial insemination in individuals that have behavioral or physical limitations,” Smithsonian’s press release reads.

After a good long life, Walnut began to slow down last month: on January 2, her keepers noticed she was refusing to eat or drink. They provided her favorite foods, but her health continued to decline.

The press release states that Walnut “died naturally with the animal care team by her side,” and that the cause of death was revealed to be renal failure.

Walnut, a truly unique celebrity at Smithsonian’s facility, will be mourned by so many — perhaps no one more than her longtime mate.

“Walnut was a unique individual with a vivacious personality,” Chris Crowe said. “She was always confident in expressing herself, an eager and excellent dancer, and stoic in the face of life’s challenges. I’ll always be grateful for her bond with me.”

Credit: Roshan Patel, Smithsonian’s National Zoo and Conservation Biology Institute

“Walnut’s extraordinary story has helped bring attention to her vulnerable species’ plight,” he added. “I hope that everyone who was touched by her story understands that her species’ survival depends on our ability and desire to protect wetland habitats.”

The white-naped crane is listed as a vulnerable species by the International Union for Conservation of Nature, suffering population losses due to habitat loss. There are now fewer than 5,300 in their native habitats.

Rest in peace to this beautiful, unique crane who contributed so much to her species — she will be missed by all, especially by her human mate 😢❤️

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