L.A. Zoo investigating death of baby chimp She didn't have a name. She was only about 3 months old, after all. But as the first baby chimpanzee born at the Los Angeles Zoo in 13 years, she had already earned a spot in the hearts of many staffers and visitors. L.A. Zoo officials spent Wednesday investigating the death of the baby chimpanzee who they say was killed by an adult male chimp in front of dozens of zoo visitors in her habitat the day before. As officials tried to figure out what went wrong, the baby chimp's mother, Gracie, spent the night with the body of her child to grieve. And she wasn't the only one. "This is going to be a big grieving period for a lot of the staff members," L.A. Zoo spokesman Jason Jacobs said. Still, some zoo visitors questioned whether the staff should have done more. Zoo patron Victoria Pipkin-Lane said she was "furious" at zoo staff because she said she saw two tussles between chimps just days before the baby was killed. Pipkin-Lane, the executive director of Los Angeles County's Quality and Productivity Commission, said she witnessed a 10-minute fight between two chimps Saturday. One of the chimps appeared to be protecting Gracie and her baby chimp. "It was scary," Pipkin-Lane said. Those of us that were near the compound were like, 'My God, why aren't they going to do something about this?' In a letter to Mayor Antonio Villaraigosa, she asked that he demand a full report and action plan from the zoo. But zoo officials said in a statement that "policy does not allow staff to enter the same space as these animals" because "chimpanzee behavior can sometimes be aggressive and violent." The chimps at the zoo live in large "fission-fusion" social groups that periodically separate into smaller units and then reconvene, Jacobs said. The baby chimp had been gradually introduced to the troop during the first three months of her life. Zoo officials said they did not have any immediate plans to change their policies regarding how and when to integrate baby chimps with the rest of the population. Chimp infanticide behavior occurs both in captivity and in the wild, said Craig Stanford, a USC professor in anthropology and biological sciences. He stressed that some acts of aggression are unavoidable. They can be very nasty animals. They abuse females, and they attack babies," Stanford said. It's shocking for visitors to see, I know, but it's something that primatologists are accustomed to seeing regularly. Jacobs said he has not yet received detailed reports of Tuesday's attack. "We just know it happened really fast," he said, adding that the male was back with the other chimps Wednesday.