SAN DIEGO (CNS) - The San Diego Zoo will officially close its panda habitat and Panda Cam Monday as it prepares its last two giant pandas for repatriation to China.

The zoo first acquired giant pandas more than 30 years ago through a loan program with the Chinese government. The zoo's conservation researchers have worked with the Chinese government since that time to increase the country's giant panda population by more than 2,000 bears.

The zoo originally planned to close its panda habitat and the wildly popular Panda Cam April 27. After an outpouring of support from zoo patrons, the zoo extended its farewell celebration for 27-year-old panda Bai Yun and her 6-year-old son Xiao Liwu by two days. The two pandas are scheduled to return to China later this spring; a third panda, Gao Gao, was repatriated last October.

TIMELINE: Pandas have a long history at the San Diego Zoo

"The panda program we began together demonstrates how powerful these collaborative efforts can be," said San Diego Zoo Global President and CEO Douglas Myers. "We are extremely grateful to China for sharing the pandas with us and offering us the chance to serve this species in a leadership role."

The zoo's conservationists plan to work with their Chinese colleagues going forward to continue their efforts to boost the wild panda population. The zoo's work with the Chinese government has led to the International Union for Conservation of Nature to downgrade the giant panda's threatened status from "endangered" to "vulnerable," meaning they are less at risk of going extinct than they were before. Zoo officials said they intend to keep that momentum going.

"Although we are sad to see these pandas go, we have great hopes for the future," said San Diego Zoo Global COO Shawn Dixon. "Working with our colleagues in China, San Diego Zoo Global is ready to make a commitment for the next stage of our panda program."