ABOUT THIS STORY | Giant pandas, native to China, are endangered. There are only about 1,600 in the wild and slightly more than 200 in captivity. Panda reproduction in captivity has been problematic despite the National Zoo's big success in 2005, when Mei Xiang gave birth to Tai Shan.
Giant panda Tai Shan is among the National Zoo's most popular attractions -- and most endangered animals -- year in and year out. (Washington Post photos.)