ATLANTA -- Zoo keepers are on 24-hour birth watch for a new giant panda at Zoo Atlanta. They expect 10-year-old giant panda Lun Lun to deliver a cub in the next few weeks.

LIVESTREAM: Zoo Atlanta's Panda Cam

Lun Lun showed a decrease in appetite and became lethargic last week.

"The bear who’s usually first in line for bamboo brunch suddenly lost interest in her morning munchies," said Atlanta Zoo officials in a news release.

Keepers say the changes are normal for a female giant panda entering the final phase of pregnancy.

Zoo officials said there's really no way to tell if Lun Lun is pregnant until she actually gives birth.

Lun Lun's first cub named Mei Lan was born on Sept. 6, 2006. Zoo Atlanta is one of only four zoos in the U.S. exhibiting the endangered species.