Zoo Map - 2010

The new Menschaffenhaus opened in april 2000 (9 on the map) and the old chimpansee house (13 on the map) was demolished shortly afterwards. The Sumatran orangutan came in 1999 en were on display in this house in 2000.

The book "Im Zeichen des Luchses. 50 Jahre Zoo Magdeburg" has a 2000 map which already mention the orangutan.

So my guess would be: 1999

This is from at least a decade later when the orangutans had moved out again, as the new rhino house is already opened, so around 2010.

You're absolutely right. I did pay too much attention to n° 13. That should also be a new construction.