Giant Panda Mama Welcomes Baby Cub at National Zoo Friday Evening

The pink, squeaking infant is about the size of a stick of butter and will be named in 100 days

A healthy giant panda cub was born today around 6:35 p.m. Eastern Time at the Smithsonian's National Zoo in Washington, D.C. The cub's sex will be determined after neonatal exams are completed at a later date. The cub, who is currently about the size of a stick of butter, will be named in 100 days.

The infant panda was born to Mei Xiang (may-SHONG), a 22-year-old giant panda who has been with the Zoo since 2000. Mei Xiang "picked up the cub immediately and began cradling and caring for it," according to a Zoo release. "The panda team heard the cub vocalize and glimpsed the cub for the first time briefly immediately after the birth."

The birth was streamed live via the Zoo's panda cam, and though Mei Xiang and her baby will remain in isolation, spectators can tune into the live stream to watch the pair interact.

"Giant pandas are an international symbol of endangered wildlife and hope, and with the birth of this precious cub we are thrilled to offer the world a much-needed moment of pure joy," said Steve Monfort, John and Adrienne Mars Director of the Smithsonian's National Zoo and Conservation Biology Institute. "Because Mei Xiang is of advanced maternal age, we knew the chances of her having a cub were slim. However, we wanted to give her one more opportunity to contribute to her species' survival. I am incredibly proud of our animal care and science teams, whose expertise in giant panda behavior was critical to this conservation success."

In the coming weeks, the blind, hairless cub-which is roughly 1/900th the size of its mother-will live on Mei Xiang's chest, migrating between mammary glands and warm armpits.

Giant pandas are literal and figurative icons of the worldwide conservation movement. And after many years of decline, their wild population is finally showing signs of improvement. The International Union for Conservation of Nature (IUCN), which monitors species at risk of extinction, announced in 2016 that pandas have been upgraded from "endangered" to "vulnerable" to reflect a 17 percent increase in their population over the past decade. Currently, around 1,800 pandas exist in the wild, with some 500 more being held in captivity.

Despite this progress, the species' recovery remains fragile due to threats from habitat loss caused by deforestation and, in the long-run, climate change. For this reason, every newborn panda is a significant victory for those seeking to ensure the species' survival.

The birth of the new cub also reflects years of progress among zoos and breeding programs seeking to bolster the panda's population. For a variety of reasons, pandas are incredibly hard to breed in captivity.

Female pandas are only capable of conceiving cubs for 24 to 72 hours a year. Nailing this timing requires careful observation of the bear's behavior as well as monitoring the rise and fall of various hormones.

Back in mid-March, when the severity of the coronavirus pandemic was dawning on people around the world, Mei Xiang became restless. According to the Zoo, she was seen wandering about her enclosure, marking it with her scent, vocalizing and playing in water, which, in combination with increasing concentrations of the hormone estrogen in her urine, signals that ovulation is imminent.

Because the panda's reproductive window is so small, and because male pandas are not terribly reliable collaborators, on March 22 reproductive scientists from the Smithsonian Conservation Biology Institute (SCBI) and Zoo veterinarians artificially inseminated Mei Xiang with frozen semen from 22-year-old Tian Tian (tee-YEN tee-YEN), the Zoo's male giant panda. Historically, Tian Tian has had trouble with natural procreation and all of Mei Xiang's previous cubs, Tai Shan, Bao Bao and Bei Bei, have been conceived through artificial insemination.

Staff then waited anxiously for months before a second rise in progesterone in Mei Xiang's urine in early June and behavioral changes in July suggested she might be pregnant. The significant uncertainty is due to the fact that pandas can have what are called "pseudopregnancies," which are identical to actual pregnancy in terms of the animal's behavior and hormone changes, but, crucially, involve no fetus. Mei Xiang has experienced seven pseudopregnancies.

Finally, on the morning of August 14, veterinarians at the Zoo detected what appeared to be developing fetal tissue on an ultrasound. A few days later, the fetus' spine and blood flow were visible as it kicked and swam about in the womb.

Mei Xiang's successful motherhood is all the more impressive and special because she's nearing the end of her reproductive life. Pandas older than Mei Xiang have given birth, but females of the species typically cease to be fertile after their early twenties.

Though the National Zoo reopened with new safety measures on July 24, the panda house at the David M. Rubenstein Family Giant Panda Habitat is currently closed to ensure Mei Xiang and her new baby are undisturbed. The panda team has been monitoring Mei Xiang around the clock since August 14 via the Panda Cam, and the public can tune in to get their panda fix there as well.