"We don't want to move too fast with her, where we stress out the baby," Evans said. "It's going to be a gradual process."
A suite has been set up for Gladys and the human surrogates, within view, hearing and smell of the other gorillas. Evans said that so far, they have responded hospitably.
"Babies have a calming effect on a gorilla community," he said. "The two females were just fixated on that baby."
Gladys is gaining weight, big for her age at nearly 7 pounds, and alert and apparently curious, looking around a lot at her surroundings.
When working on her transition plan, Evans considered bringing in veteran neonatal nurses, but decided that familiarity with gorilla behavior was more important. As the baby progresses, volunteers who have worked with gorillas may be added to help.
Zoo spokeswoman Tiffany Barnes said the surrogate effort has drawn wide interest, with thousands of emails and social media responses already. There have been plenty of volunteers from the public to cuddle and bottle-feed the baby gorilla or otherwise help out.
"At this point, we aren't in need of volunteers, as we are using zoo staff members who have ape behavior knowledge and experience," she said. "That being said, if we ever needed volunteers, we know we don't have to look far."