Indian rhinos were part of the original Asia Trail phase 2 plans back in 2003, but never materialized off paper. Phase 2 also was to included the otters (which ended up built during phase 1) and ultimately only became Elephant Trails after costs ballooned. You can still see the empty field along the boardwalk between the clouded leopards and otters where the rhinos were to be located. Part of phase 2 also included space for future Asian animals including gibbons, siamangs, cranes, and camels in a large empty patch south of the sloth bears and north of the new bird plateau. There are always these nice grand plans until reality hits...