That is the number one lesson that should be learned by every Zoo! The elephants at Copenhagen LOVE the sand. It is such a joy to see them enjoying it, outdoors as well as indoors.
The same goes for the bull enclosures that I have critizised here on ZooChat. They love the sand just as much as the herd.
Just think of what a cheap and relatively easy way this wcould be to enrich the elephants in old and out of date enclosures!
Every day: BULLDOZE in a couple of heaps of sand, bury some treats in it and let the animals enjoy!