Human caregivers placed new objects in the chimpanzee areas every day: blankets, catalogs, books, magazines, sheets, clothing, shoes, toys, paper, crayons, pencils, water pistols, stuffed animals and more.

We developed themes for object enrichment every day--Green Day, Soft Items Day, Harry Potter Day, and so on and so on. These helped ensure that the chimpanzees always had new combinations of objects with which to interact.