The last U.S. zoo with pandas in its care expects to say goodbye to the four giant bears this fall.

Zoo Atlanta is making preparations to return panda parents Lun Lun and Yang Yang to China along with their American-born twins Ya Lun and Xi Lun, zoo officials said Friday. There is no specific date for the transfer yet, they said, but it will likely happen between October and December.

The four Atlanta pandas have been the last in the United States since the National Zoo in Washington returned three pandas to China last November. Those pandas flew to China on Nov. 8 and 24 later landed in Chengdu where the Chinese National Zoo is located. Mei Xiang and Tian Tian were on loan for a research and breeding program. In 2020 the couple had a baby named Xiao Qi Ji, who also returned to China. Forklifts had to move the giant pandas to the airport in trucks where they boarded a special flight with "snacks," including around 220 pounds of bamboo. 

Pandas were first sent to D.C. to save the species by breeding them, and couples have been kept at the zoo ever since. 

Other American zoos have sent pandas back to China as loan agreements lapsed amid heightened diplomatic tensions between the two nations. In addition to Atlanta and Washington D.C. zoos, the Memphis Zoo and the San Diego Zoo were the only others in the U.S. to have housed giant pandas. Memphis returned its last surviving panda in April 2023. San Diego returned its pandas in 2019 more than three decades after the first couple's arrival in 1987.

Atlanta received Lun Lun and Yang Yang from China in 1999 as part of a 25-year loan agreement that will soon expire.

Ya Lun and Xi Lun, born in 2016, are the youngest of seven pandas born at Zoo Atlanta since their parents arrived. Their siblings are already in the care of China's Chengdu Research Center of Giant Panda Breeding.

It is possible that America will welcome a new panda pair before the Atlanta bears depart. The San Diego Zoo said last month that staff members recently traveled to China to meet pandas Yun Chuan and Xin Bao, which could arrive in California as soon as this summer. San Francisco Zoo also recently signed in April a memorandum of understanding with the China Wildlife Conservation Association to bring pandas to the zoo. In the 1980s pandas were briefly hosted at the zoo, but the agreement marks the first time pandas will reside at San Francisco Zoo. 

Zoo Atlanta officials said in a news release they should be able to share "significant advance notice" before their pandas leave. As to whether Atlanta might see host any future pandas, "no discussions have yet taken place with partners in China," zoo officials said.

There are just over 1,800 pandas left in the wild, according to the World Wildlife Fund, and although breeding programs have increased their numbers, the panda's survival is still considered at severe risk. 

Reporting contributed by Caitlin O'Kane.

In:
• China
• Giant Panda