I think this revelation, coupled with your interesting (but unfortunate) remarks on the negative trajectory of the Tierpark's bird collection due to mismanagement
Well, mismanagement isn't exactly the right way to put it, and more that the pheasantry and surrounding area have long been earmarked for demolition and replacement with a massive picnic meadow in the masterplan that Andreas Knieriem introduced when he became director in 2014:

As that map shows, there *is* a plan to eventually create a massive walkthrough aviary complex nearby, on the current site of the gibbon enclosure and surrounding exhibits, but in the meantime the Pheasantry very much feels like it is being gradually wound-down.