The idea of rotating animals through several exhibits as a means of enrichment and variability is a relatively new one. The popularity of the idea is widespread, despite the requirements of large spaces, intensive staff involvement, and complex (or flexible) holding facilities. Generally, we've been incorporating some sort of rotation capability in all of our exhibits for the past several years. If the staff is willing, the advantage is great: providing several smaller exhibits in which to rotate through the animals during the day provides active animals, which in turn, provides engaged guests.
The upcoming Louisville Zoo Glacier Run exhibit takes full advantage of this type of exhibitry. Despite the main exhibit area being on the small size, the bears here will have several play areas away from the main exhibit, thereby increasing the overall territory of the animals. The downside to this is casual visitors may not understand the complexity of the bears' lifestyle, and may judge the exhibit as inadequate.
However, understanding how to incorporate this important concept will enhance most zoo exhibitry, and many times, is a creative solution to a tricky problem. Read more about rotation from da man, Jon Coe, here.