Because of budget cut the Forest Buffalo left and the red river hogs moved in with the waterbucks. It would not make sense to add more species which would add more costs.
The zoo no longer has birds on exhibit in Habitat Africa! The Forest. Red duikers are in the old bird exhibit, and elephant shrews are in the old duiker exhibit. All the reptiles are still on exhibit and haven't changed. The zoo exhibits yellow-backed duikers and red duikers, so they still have two species. Also, the only exhibit that isn't being used is the old red river hog exhibit. Okapi have access to the old forest buffalo exhibit, but you can't get close enough to view them in that exhibit. You can still see the okapi in 4 visible exhibits.