Within an hour of opening on Monday, crowds of people were chatting happily amongst themselves in the Smithsonian National Zoo and Conservation Biology Institute as they waited for Xiao Qi -- the star of the day -- at the Panda House's outdoor enclosure.
As soon as the birthday boy appeared, meandering toward his birthday "Young, Wild and 3" themed treats, an excited hush fell over the crowd.
Xiao Qi Ji, the youngest giant panda at the National Zoo, turned three on Monday. The Smithsonian celebrated the occasion in style, presenting a showstopping fruitsicle cake made with panda-friendly apple and pineapple juice, mashed sweet potatoes, carrots, honey, and leafy bamboo sprigs.
But the celebration was bittersweet, because it's the last time Xiao Qi Ji will celebrate his birthday in the District.
Xiao Qi Ji will fly back to China alongside his parents, Mei Xiang and Tian Tian, by this December, when the contract between research institutions in the U.S. and China expires.
"I'm very sad; I will miss him very much," said Rachel Weidner, a tourist who came from Philadelphia to visit Xiao Qi Ji on his last birthday in the U.S.
She sported an entirely black-and-white outfit, complete with a headband topped with mini panda-head ears, in the hopes that the pandas might see a kindred spirit and "come and say hi" when she stopped by the zoo.
"But I know that he will be well taken care of," Weidner said. "And I know that I can still follow him, and maybe even come visit him some day."
Since the beginning of the research exchange program, the pandas have always served as a kind of soft diplomacy between the two countries.
The first pair of pandas, Ling-Ling and Hsing-Hsing, were gifted in 1972 to commemorate President Richard Nixon's trip to China that year.
The second pair, Mei Xiang and Tian Tian, have called the zoo home since 2000, when they were gifted to the Smithsonian institution by the Chinese government.
An agreement with China in 2000 "stipulated [Mei Xiang and Tian Tian] would live at the Zoo for 10 years in exchange for $10 million," according to the zoo's website.
A decade later, the Smithsonian and the China Wildlife Conservation Association signed a new Giant Panda Cooperative Research and Breeding Agreement in January 2011. That agreement stated the pandas would stay at the zoo until December of 2015.
The contract was extended to 2020, then again to 2023, shortly before each previous contract expired.
According to the National Zoo, all three giant pandas that currently call D.C. home will leave by Dec. 7. And so far, the zoo hasn't shared any insight into when the next round of pandas will arrive -- or if there are more pandas on the way.
Despite the soft diplomacy background, the negotiations are researcher-to-researcher and not based in politics.
"We're a bunch of scientists; we're a bunch of animal people," Zoo Director Brandie Smith told New4. "This is not a political conversation. This is absolutely a conversation between colleagues talking about, what's best for the overall program, and also, what can be best for individual animals?"
For now, it appears that a return to the China Wildlife Conservation Association is the answer.
The two older pandas will get "a luxurious retirement," while Xiao Qi Ji might find his own mate in a place with more pandas, Smith said.
"As per our agreement with our Chinese colleagues, [the pandas] are to go back to China by the end of the year," Bryan Amaral, senior curator at the National Zoo, told News4. "So, we're just fulfilling that obligation."
He described the China Wildlife Conservation Association grounds as "a panda base, if you will."
"It's a place where they have lots and lots of giant pandas, very similar to what you would see -- how our giant pandas live here, very similar to that," Amaral said. "They just have a lot more giant pandas than we have. Where we have elephants and, you know, all kinds of other things, they have just pandas."
To get to that panda base, Xiao Qi Ji, Mei Xiang and Tian Tian will have to fly back to the other side of the globe. But the three pandas will be well-prepared for the journey, with National Zoo staff traveling alongside them.
The trip may not be the most fun, and it may be "logistically challenging," Amaral said, but "we prepare them, we train them to go into their specially designed transport containers, and it should be no big deal."
The direct flight bringing them back will be "as short as possible, just like we would all appreciate," Amaral said.
And while 3 years old may sound young to undertake such a journey from a person's perspective, in panda years, Xiao Qi Ji is "a college kid," Amaral said.
"He's way old enough to handle all this kind of stuff on his own. He's actually our largest cub at his age that we've had at this point. So he's more than ready to tackle the world on his own now," Amaral told News4.
Much like a college kid moving out, it's a big change for the pandas and for their caretakers.
"I see him sometimes and it takes me a second to realize that our little baby is now grown up and as big as his parents," Smith told News4. "But he's doing great, and he's in for a big celebration today."
She, too, knows that Xiao Qi Ji is ready to go.
"We prepare for this, you know," Smith said. "The success for these animals is to grow up, to return to China, to be part of the bigger breeding program and make more pandas."
"Our goal is to save a species," she added. "The fact that we can have giant pandas here and everybody gets to help us and enjoy it, that's just an extra bonus."
Even so, Smith, Amaral and the other zookeepers will miss all three pandas as much as the rest of D.C., making it bittersweet to see the pandas leave.
The panda parents predate Amaral's tenure at the Zoo, but Xiao Qi Ji was born after Amaral arrived -- and just one day after Amaral's own birthday.
"So watching him come into the world and waiting anxiously for him to come into the world, I was secretly hoping that he would share a birthday with me," Amaral said. "But no dice on that one."
Smith is "optimistic" about pandas returning to the National Zoo, though an exact timeline isn't clear, yet.
Any intermediate time between panda residents will be used to improve the panda habitat, adding things like extra climbing structures and better air conditioning and smoke detection systems.
"No matter what happens, we are going to continue our giant panda conservation work, the stuff that we are doing, you know, in the field to save pandas, to save the species and our hopes," Smith said. "My dream is that giant pandas will return to the National Zoo sometime in the near future."
If and when more giant pandas arrive at the zoo, history suggests they'll be welcomed with open arms and celebrated every step of the way.
After years of watching the pandas grow, it's no wonder the zoo scientists -- and residents of the District -- form personal attachments.
Xiao Qi Ji certainly seemed to enjoy his fruitsicle cake, lying on his side, gnawing and pawing at the icy snack, and luxuriating in the grass while the crowd broke into a spontaneous chorus of "Happy Birthday."
"You can see how attached and emotional and passionate people are about it," Amaral said. "And we feel exactly the same way."
"I'm excited for their future," Smith said, "although I'm a little bit heartbroken for us."
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