I'd just like to add to that. I recently visited Bannerghatta zoo as part of my school trip and was horrified by some of the conditions there, I wish I had never been. I saw elephant "keepers" prodding the elephants around with sticks with sharp points, ducks and geese in a concrete enclosure with filthy water around the edge and much more. I got photo evidence of this which I intend to send to the relevant authorities (WWF, as there name seems to be on the signs, Karnataka state tourism dept, and the zoo itself.