@Jonathan Harry
The Rookmaker mentioned that the animals in Surabaya lived on a 0.5 ha moated island, designed to house one pair of rhinos. The viewing platform is also mentioned. I have the impression that this is the island currently occupied by Proboscis Monkey and Bawean Deer. What's are your thoughts about it?
@twilighter Maybe you're right because this enclosure is surrounded by an iron fence, while the current fence on Proboscis Monkey Islands is almost invisible.