From a photographer's perspective, we had our camera bags and monopods. The day we were there, the zoo was packed and tripods would have been hard to use.
Coolers, wagons, and strollers welcome. Obviously no alcohol, and also no smoking allowed (even e-cigs not allowed) there are plenty of places to refill a water bottle, and also 4 or more places to sit at a table and have a picnic. I do recommend the giant pretzel in the African eating area, kinda expensive but delicious. And don't forget comfy shoes! Lol
No weapons, alcohol, drugs, etc. Other than that, you are pretty free to bring things. Assume you are asking about food and drinks. Any of the normal things are fine. Picnic items are brought by many.
Enjoy and have fun! It's a great zoo!!!
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