Zoo keepers have fingers crossed for a panda birth

She's gotten lazier, lost her appetite, and insists on hiding in a darkened room near a nest of bamboo stalks. Ling-Ling, the female giant panda, is apparently ready to give birth, her National Zoo keepers say.

''We've been told that before pandas give birth they begin nest building,'' a zoo spokesman said. ''Last Friday Ling-Ling started carrying around nesting materials.'' Veterinarians cannot detect pregnancy because a cub's birth weight is about 4 ounces.