More than 70 years after the Berlin Zoo forced Jewish shareholders out of its ranks, the institution is trying to come clean about its dark chapter during the Nazi era.

A Berlin historian is combing through thousands of names to identify members made to sell their shares back to the zoo at a loss under the Third Reich, and has begun tracking down their descendants.

Historian Monika Schmidt estimates up to a quarter of the zoo's 4000 shareholders in the 1930s were Jewish.

"But they were pushed out step by step by the zoo itself, before the Nazi state asked any institution to do those things," Schmidt told AFP....