Well ok. I wonder if the new one (which is a physical sign) is oriented to how you are looking at it when you are standing in that spot? I recently read a book about enhancing the visitor experience at zoos, museums, nature centers. The author states that every physical sign map should be different because it only makes sense to people if it is oriented based on the direction they are facing when they look at it.
That's exactly the case here AD, and that was the only reason I could think of that made any sense. All other maps for as long as I can remember (and even older ones I've seen in archives) have the harbour either at the top, or at the bottom.
The above map is on a post just before the Koala House. When I thought about it I looked to see if there were any other similar maps in the zoo identical or differently oriented, but I didn't see any (then again, when you know the zoo back-to-front you tend to ignore any maps and signs).