The orang is Azimat and I think the gorillas are Kumba and Kukee, although there was a third gorilla, Lomie, in the enclosure at the time. All these apes arrived at the zoo around the time it opened, just over a year before I took this photo. Note the original state of the outdoor ape enclosure, now used by the orangs.
In the background note the penguin pool, which subsequently housed otters, and some construction work. Scanned from a Kodachrome slide.