That enclosure, between the Cotton Terraces and the Clore, has held several species. For many years it held beavers, then porcupines, if I remember rightly, and even rhinoceros iguanas (in the summer of course).
@ Marwell Dalek: Sorry, I was under the impression that this was the enclosure next to the new one (the sign in the photo states that this exhibit houses meerkats) - when we were there, a keeper was feeding them and explained that a tunnel had been constructed to give the meerkats freedom to use either exhibit.