Cincinnati Zoo officials are in San Francisco Monday for a court-ordered mediation with California-based The Gorilla Foundation.
At issue is the future of a gorilla named "Ndume." A spokesman says the zoo is hopeful Monday's meeting will be successful.
The zoo loaned the 37-year-old silverback to The Gorilla Foundation in 1991 as a companion for the famous gorilla "Koko" who died in June. The foundation is now refusing to return him, citing concerns for his health.
"We're very concerned about him surviving the transfer," says an attorney for the foundation, David Casselman. "Trying to [get him] reintegrated there would be very, very difficult, so we're hoping we can find a way to work together with the zoo as we did before to find companions for him out of the zoo environment where he will thrive."
The Cincinnati Zoo filed a lawsuit in federal court in California in October after it says negotiations with The Gorilla Foundation for Ndume's contractually required return broke down.
Zoo Director Thane Maynard told WVXU last month the zoo has consulted with top ape experts about the transfer, adding moving such animals around the country is routine.
Maynard also says keeping Ndume in isolation, as he has been since Koko's death, is not good for his health because gorillas are social primates that need to live in groups.
The foundation argues a public zoo environment would lead to a return in negative and unhealthy behaviors and Ndume should remain in its private sanctuary.