Hello, Pine
I believe that historically the first GLAM project in a Zoo was the one which we implemented in Bulgarian Wikipedia together with Sofia Zoo back in 2012-2013. It was funded by the Wikimedia Foundation (proposal - [1], report - [2], bg coordination page - [3]).
For a brief overview, you can check two presentations in English -- one presented by me at the OpenGlam Conference 2013 in Warsaw and at the CEE Meeting 2014 in Kiev [4], and another, presented by the Zoo collaborator Katerina Zareva at the EZE Conference 2015 in Lisbon [5].
Practically, the Skopje Zoo project, which Alex mentions, came as an outcome of the Sofia Zoo project (the first discussions being initiated in November 2013).
Bests,
Vassia / Spiritia
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