"Any accident is a concern. While it may be minor in nature, we take it very seriously to see if there's anything we can do to prevent it from occurring again," said Hill, the zoo's vice president of internal relations.
He said the girl, between 3 and 5 years old, visited the zoo with her mother on Wednesday. The zoo learned about her fall afterward, when an employee saw the mother with the child bleeding in a stroller. The zoo offered first aid and a bandage for the cut. The zoo did not identify the mother and child further.
Hill said the zoo did not report the fall to any outside agencies. Zoo officials said there was no contact, or near contact, between an animal and a visitor.
The zoo's horticulturists routinely work in the grassy section near the sun bears where the girl fell, because the zoo considers it a secure area, said Steve Bircher, curator of mammals. He said exhibits were continuously evaluated, and any problems that arise would be addressed.
At the zoo, some visitors were spotted holding their children up against the rail for a better view, a practice the zoo discourages.
In 2004, one of the sun bears wounded a keeper, who sustained cuts, in a part of the exhibit away from public view.
Zoo safety has particularly been in the spotlight since a tiger at the San Francisco Zoo killed a teenager, mauled his two friends and was shot to death by police after escaping an enclosure on Christmas Day. That enclosure was determined to be lower than recommended, and it has since been rebuilt to exceed national standards.