In the background you can see the old exhibit that held various animals, most recently wild dog and prior to that maned wolf. It was seen on the old moving sidewalks that went up the hill. The sidewalks are gone and the exhibit is no longer in use (that I know of), but appears to be intact.
Another great photo @Arizona Docent ! Was this near closing time at the zoo? The African Penguin exhibit is aesthetically very pleasing from this angle and the underwater viewing area with Leopard Sharks is terrific. It would be great to see the zoo add a popular species to the area above the penguins.
Yes this was near closing time - you can see the setting sun on the horizon to the left. (In fact I rushed out of the zoo to get photos of the sunset and dusk on the harbor). The following morning I only had an hour and a half at the zoo before I had to drive home, but I managed to see the penguins swimming underwater.