ivebeen_there

At the zoo I work at, the two males only spar halfheartedly. We can usually distract them by holding up a head of lettuce and calling their names really loud.

Not OP, but I do work at a zoo. The answer to your question is basically "none". I mean, you could release them, but they'd all die almost immediately.

What changes would you say are your priorities?

Also, I just want to say thank you for bringing attention to this situation! Too many people vilify zoos while blindly supporting places like this. I firmly believe that animals can live happy lives in human care, but it has to be done right, I hope you guys can make a difference here for these chimps.