Pygmy Hippo/Wolf's Guenon exhibit

yeah, can't say for certain but I'm pretty sure those are ISIS "ghosts"

ISIS is absolutely useless when it comes to the San Diego Zoo. The system works for the majority of other establishments, but San Diego has 50% of its animal collection behind the scenes and the other 50% changes faster than Tasmania's weather. I love ISIS, but I abandoned it years ago when it comes to the world famous San Diego Zoo.

Let me refer you to an informative post by Zoochat member Ungulate on this very subject

http://www.zoochat.com/22/isis-glitches-21560/#post62366