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Giant Panda Birth News

Bai Yun Gives Birth (August 2, 2005)

After several months of waiting to see if the San Diego Zoo’s female giant panda was pregnant, 13-year-old Bai Yun gave birth to a single cub Tuesday evening, August 2, following a 3-hour labor.

The Zoo’s animal care staff observed Bai Yun give birth at 9:57 p.m. (Pacific Time) via a close circuit camera installed in the Giant Panda Research Station birthing den. The gender of the newborn will not be known for a while.

The San Diego Zoo now has the largest population of giant pandas outside of mainland China, while this birth marks the third giant panda cub to be born at the San Diego Zoo.  Currently the Zoo has four giant pandas, including Bai Yun and her newborn cub, the male panda Gao Gao, and Mei Sheng, a male cub that will be 2 years old August 19.  

The birth of this cub is the second giant panda birth in the United States this year; the first birth was at the National Zoo in July.

Several disciplines came together to determine Bai Yun’s pregnancy with tools such as thermography, hormone assay, behavioral studies, and ultrasound, but it was not until the Zoo’s animal care staff detected the presence of two fetuses implanted in the adult panda’s uterine horns through ultrasound technology that a pregnancy was announced in July.  However, on August 1 the Zoo’s veterinary staff announced the second fetus was resorbed in the womb leaving only one viable fetus.  This is the first time a giant panda pregnancy was documented this far along, providing insight into fetus development.

Gestation in giant pandas has been estimated between 97 and 163 days, making it difficult to predict a birth date accurately.  Through the use of ultrasound technology, additional images captured a rapid increase in fetal growth and development.  In response to the new images, researchers began 24-hour observations of Bai Yun on July 29.  

Bai Yun gave birth twice before. The first time was August 21, 1999, when a female cub, Hua Mei, is born at the San Diego Zoo’s Giant Panda Research Station.  Hua Mei was the first surviving giant panda to have been born in the United States.  She is now in the People’s Republic of China as part of the giant panda breeding and conservation program and gave birth to twins last year. Bai Yun’s second cub, Mei Sheng, can be seen at the Zoo.

In an effort to impact the decline of wild populations, the Zoo, working with the World Wildlife Fund, U.S. Fish and Wildlife Service, the China Wildlife Conservation Association, and the Chinese Association of Zoological Gardens, has committed significant resources to the long-term study of giant pandas in captivity and in situ conservation efforts to reverse the situation.  It is estimated that there are approximately 1,600 giant pandas left in the world due to habitat destruction and fragmentation, bamboo depletion, and poaching.  The San Diego Zoo contributes more than $1 million each year to China, part of which is designated for wild habitat protection projects.