I have been doing volunteer training at the Oregon zoo. Part of the training is tours with older volunteers, where we have been hearing interesting stories about the personalities of the animals.
The chimps seem to beleive that they are part of a union. They work set hours and get very angry when the zoo does afte hours functions. So their area is closed.
The orangs are very strong, and like to undo anything they can get their hands on. They used to have grass in their enclosure, until they took off the drain cover and started playing frisbee with a 6" diameter 1/2" thick piece of cast iron.
The elephants are very smart, but also pretty juvinile. The cows have to be restrained during some feeding times, as they try and steal each others special diet stuff. One of them ( One of the few that came from the wild) has food issues where she likes to take her ration of hay and eat by herself. The other cows tease her about this.
It has been pretty fun.
One of the things the zoo does is provide ice for some of the animals to play in. I have got to deliver it sometimes. I made movies, which are on the Zoo Guides face book page.