There may not be another species on the planet that garners more affection and enthusiasm than giant pandas.
“They’re rare, charismatic, and iconic, and humans are genetically programmed to like them,” said Brandie Smith, director of Smithsonian’s National Zoo in Washington, D.C., and the Conservation Biology Institute in Front Royal, Va. “Babies are designed to appeal to us, with their big, round eyes. Our whole idea of ‘cute’ is embodied in the giant panda.”
The species gained a soft spot in the American consciousness when the press heralded the arrival of Ling-Ling (female) and Hsing-Hsing (male) at the National Zoo and Conservation Biology Institute in 1972. The pair, a gift from Premier Zhou Enlai to the American people following a state visit by President and Mrs. Nixon, were the first giant pandas at a U.S. zoo.
The National Zoo and Conservation Biology Institute recently marked 50 years of having giant pandas, an ideal time to highlight how a gesture of goodwill has led to the creation of an impressive breeding, research, and conservation collaboration between the U.S. and China.
During Ling-Ling’s and Hsing Hsing’s two decades at the Zoo, they produced five cubs, all of which died at birth or shortly thereafter. Ling-Ling died of heart failure in 1992 and Hsing-Hsing had to be euthanized in 1999 due to terminal kidney disease.
In 2000, a new phase began in the relationship between the two countries, when the National Zoo and Conservation Biology Institute and the China Wildlife Conservation Association (CWCA) entered into a Giant Panda Cooperative Research and Breeding Agreement. It stated that the Zoo would receive a new pair of pandas, Mei Xiang (female) and Tian Tian (male), which would live there for ten years in exchange for $10 million. The agreement, which has been renewed three times since 2010, has fostered an exciting slate of cooperative ventures between the two countries.
“A lot of the first trip [to China] was networking and meeting our partners and talking about future collaborations,” said Don Neiffer, chief veterinarian National Zoo and Conservation Biology Institute. “One of the things the program shows is that countries with different ideologies and value systems can set those aside for the benefit of the species. I’ve had very open, candid, fluid discussions and there’s never been a feeling that one’s intruding on the other.”
Under the auspices of the agreement, the two priorities for the National Zoo and Conservation Biology Institute are to maintain a healthy, viable giant panda population in human care while also working to save the species in the wild. And Smith attributes many of the program’s successes to the fact that panda conservation extends beyond the scientific community. In fact, she looks at working with pandas as “soft diplomacy.”
“We have a program where scientists and researchers in both countries are working to preserve the giant panda. But because they are such an iconic species around the world, it’s not just scientist to scientist—we engage at all levels. We always think to include the embassies. We are moving the needle on giant pandas because of the attention they receive socially, politically, culturally, and scientifically. We have a 360-degree conservation program. When anyone says to me, ‘The pandas receive too much attention,’ I say it’s that other species don’t receive enough. This is what it takes.”
During the ongoing effort to breed pandas, Mei Xiang experienced multiple pseudopregnancies and bore one cub that died shortly after birth. However, between 2005 and 2020 she gave birth to four cubs that lived. All of them were the result of artificial insemination, and, because timing is everything about female fertility, hormone technology was integral to the breeding success.
“Females are only fertile for 24 to 36 hours once a year, and their behavior doesn’t always line up with the hormones,” said Janine Brown, research physiologist and head of the endocrinology lab at the National Zoo and Conservation Biology Institute. “We measure the rising estrogens to try to find when it peaks. When we track the levels going up for several days, we take the machine to the Zoo and run assays every time she pees—every four to five hours. We’ve also been working on trying to make the assays quicker so we can get answers faster.”
“When Mei Xiang became pregnant from an insemination we were hoping for the best and AI worked,” said Pierre Comizzoli, DVM, research veterinarian. “And what was even more exciting was that Tai Shan [born in 2005] lived.”
Subsequent inseminations resulted in the birth of Bao Bao in 2013, Bei Bei in 2015, and Xiao Qi Ji in 2020. Although the first three procedures used fresh semen or a combination of fresh and previously frozen, the fourth represented another breeding milestone for the U.S.
“2020 was the first year we were able to get a pregnancy and a live cub using frozen semen only … which was a huge proof of concept for us,” said Comizzoli. “Having that success makes us excited to repeat it multiple times and reliably use it for the population of wild pandas.”
Keeping the National Zoo and Conservation Biology Institute’s pandas healthy falls to Nieffer’s staff, with critical assistance from the keepers and the involvement of the pandas themselves.
“Giant pandas are predictable. If I have a sick panda, there’s a logical path to follow and we have a pretty good idea of what’s wrong. Across all life stages, they have gastrointestinal issues because they’re carnivores that have evolved to eat grasses. As they get older, they have issues with high blood pressure, cardiac disease, and arthritis.”
“The pandas’ willingness to undergo voluntary blood draws and blood pressure checks only happens because of the trusting, one-to-one relationships they have with the keepers. They start very early using treats for positive reinforcement … and pandas are extremely food motivated. There’s no coercion and the pandas can walk away if they want to, but they won’t get a treat.”
With the shared goal of ensuring the sustainability of giant pandas in the wild, individuals from the National Zoo and Conservation Biology Institute have conducted 60-plus training courses for more than1,500 professionals and students in China who are affiliated with panda reserves, universities, and forest departments. Subject areas include GIS and remote sensing, biodiversity survey techniques, and genetic management in addition to endocrinology, biomedical, and diagnostic training. The breadth of this capacity-building not only helps take China’s current panda conservation work to the next level; it also contributes to the education of the next generation that will continue those efforts.
The three main issues affecting the viability of giant pandas in China are lack of connectivity among the populations; the need for habitat restoration; and the emerging threat of climate change. To obtain information that will inform their decisions and recommendations, the National Zoo and Conservation Biology Institute team has collaborated with students and rangers to collect data from 31,000 camera nights in 953 locations.
“There are now about 2,000 giant pandas in 33 separate populations over six mountain ranges,” said Mel Songer, conservation biologist. “Fragmentation is a big problem, because about half of those 33 have less than 20 pandas, so there are concerns about genetic diversity. We need to increase connectivity of the populations.”
Fortunately, habitat destruction stopped when the Chinese government banned logging, so the focus is now on adding new protected areas, restoring bamboo forests, and developing corridors of those forests to link the fragmented populations. The National Zoo and Conservation Biology Institute team has worked with communities and local reserve staffers to restore bamboos plots, and they have already seen fecal evidence of pandas returning to some of those areas.
Ensuring species sustainability includes focusing on climate change, determining how it will affect habitats, and formulating strategies to address the threat. Songer and her colleagues are gathering data that will help their Chinese counterparts make sound, science-based decisions.
“It’s very complicated to say, ‘We should save this area,’” she said. “A lot of climate change work is modeling for 2030 and 2050. We can’t go in and tell them what to do, but we’re developing publications that will inform their decision making, with recommendations based on lots of research.”
As part of the agreement, Tai Shan, Bao Bao, and Bei Bei all went back to breeding centers in China when they were four years old, and Xiao Qi Ji will follow when he is old enough. Tai Shan has sired one cub and Bao Bao has given birth to three. Having them leave is a difficult but necessary part of the process, according to Laurie Thompson, assistant curator of giant pandas. She accompanied Bei Bei on his return trip.
“We’re sad but we’re prepared for it. It’s bittersweet—kind of like sending your kid to college. Our job is to get them ready to go off and do what they’re supposed to do,” she said.
In 2016, giant panda status was upgraded from “endangered” to “vulnerable,” a result of focused breeding and conservation efforts, including the work done by National Zoo and Conservation Biology Institute and CWCA. Their agreement is due to be renegotiated in 2023.
“We are absolutely committed to having giant pandas, and we are already engaged in conversations about the future,” said Smith. “We have such a good relationship with China, and this is such a positive program for everyone involved, I don’t see any reason not to continue.”
Imagine what could be accomplished in the next 50 years.
Mary Ellen Collins is a writer based in St. Petersburg, Fla.