I very much like it, Orycteropus. I do find it frustrating how often you have to wade through hundreds of photos to find the ones that focus on the exhibit you're trying to look at.
Maybe a sub-set of the galleries could be dedicated to specific 'signature' exhibits? For instance, under Bronx Zoo you might find galleries for Congo Gorilla Forest, Madagascar, Wild Asia, Baboon Reserve, World of Birds, Jungle World, Tiger Mountain and Himalayan Highlands. Would make using the gallery - especially for zoos with hundreds or even over a thousand photos - easier to use.