"It’s not immediately clear what will happen to the panda habitat when they leave.
“We’ll take this time to update the indoor habitats and we may exhibit other animals while there are no pandas at the Zoo. No confirmation of what animals may go on exhibit at this time,” a spokesperson writes via email...
It remains possible pandas could one day come back to the National Zoo. A year after
the death of Hsing-Hsing in 1999, the Smithsonian Institute and China came to
another agreement for pandas to once again live in the nation’s capital. That remains the zoo’s hoped-for scenario.
“We’re working with our Chinese partner, the China Wildlife Conservation Association, to develop a future giant panda program,” a National Zoo spokesperson tells DCist/WAMU via email. “After 51 years of success, we remain committed to giant panda conservation. One thing is certain, the Zoo’s panda program has made a major impact on panda conservation and will continue to do so in the future.It’s our intention to have giant pandas at the Zoo in the future and continue our research here and conservation work in China.”"
https://dcist.com/story/23/10/10/smithsonian-national-zoo-giant-pandas-dc-loses-unofficial-mascot/