The cheetah scaled a wall at least 10 feet (three meters) tall on Monday and got into a rocky area that separates animals from people at the River's Edge exhibit. The area was quickly evacuated. Twenty-seven minutes later, the cheetah was found, tranquilized and returned unharmed to its exhibit.
"We have no idea how the cat got up there," said Jack Grisham, vice president of animal collection for the zoo, on Tuesday. "We have a million theories. It could have been the cats playing with one another and it made the lucky jump - or unlucky jump."
The cheetah, a female named Zuri, weighs 40 to 45 pounds (18.1 to 20.4 kilograms), Grisham said. She is one of four born on Nov. 10, 2006 , at the zoo - the first new litter here since 1992. One of the cheetahs died a month later.
Grisham said a visitor noticed the loose cheetah and notified a zoo worker. Security workers cleared the River's Edge area and all zoo visitors were told to get inside a building.
Grisham said the animal apparently did not threaten any patrons.
Cheetahs are more docile than most other big cats, Grisham said. Still, "any wild animal could be a danger to the public," he said. "These animals are not pets."
The incident marked the third time since 2000 that a cheetah has escaped from the zoo enclosure. In both previous instances, changes were made to offer better protection to the public - fencing was increased and a moat separating the animals and visitors was widened.
Zoo officials were evaluating if additional changes need to be made. Grisham said a cheetah under normal circumstances should not be able to jump to the top of a 10-foot (three-meter) fence.