The gorilla at Riverbanks Zoo and Gardens ran into a pizza-stand employee who curled up and played dead to try to avoid further injuries, officials said. The man, who works for Aramark Corp., was taken to a hospital and released a short time later with cuts and bruises.
Zoo executive director Satch Krantz said the worker heard a strange sound, saw the gorilla outside the enclosure and turned to run.
"Then the gorilla did what gorillas do," he said.
The animal quickly closed the 9-m gap between them and knocked the worker down. Two minutes later, the gorilla went over another wall and back into his enclosure.
"By then, the gorilla realized he was probably somewhere he shouldn't have been and wanted to go home," Krantz said.
The culprit is believed to be a 16-year-old western lowland gorilla named Mike, though zoo officials said they didn't know for certain. Three gorillas are in the exhibit.
Krantz praised the worker for doing the right thing. Neither he nor the company would identify the man.
Zoo officials said they were alerted to the escape by a bird-keeper who heard the commotion and the gorilla pounding on his own chest. About 340 people were ushered to indoor exhibits or outside the gates for about 45 minutes after the gorilla escaped, zoo officials said.
Krantz said employees reacted by the book and "it was an excellent job of preventing a more serious situation." The gorilla got out about a half-hour after the zoo's 9 a.m. opening. He returned to the gated sleeping area connected to his outdoor enclosure, which is separated from the public by different barriers in different spots, including mesh and plexiglass.
A second gorilla, 15-year-old Kimya, also went inside the sleeping area after the escapee returned. It took another 40 minutes for workers to coax the zoo's oldest gorilla, 24-year-old Chaka, into the sleeping area.
Animal keepers patrol each enclosure every morning before opening the zoo and nothing looked out of the ordinary in the exhibit, Krantz said.
Officials believe a powerful rainstorm Thursday night swept a clump of bamboo over the top of the enclosure wall. Krantz showed reporters photos of a zoo worker using the slim bamboo reed to climb the wall and images of gorilla footprints on the wall.
"We learned something today," he said.
Krantz said zoo officials will check vegetation around exhibits to prevent further escapes. He said he thought the gorillas would be kept penned up - and not allowed into their outside enclosure - until at least next week.
Officials said the zoo's only other escape by a dangerous animal was in 1974, shortly after it opened, when a polar bear got out because of a worker's mistake. It was quickly recaptured.
