I should have pointed out, (if I remember correctly) this exhibit was originally meant for macaques (maybe Barbary Apes) but after they had all gone Spider Monkeys were put on the island as a temporary measure and they seemed to take to it so they remained there. I recall seeing some of them wading in the shallows on their hind legs to get at some leaf or tit-bit floating past.
Well, my memory's not that crash-hot after 20 years, but I was sure that was the story. Maybe the Macaques were there in the '30's? It's an old looking exhibit.
