@Jo Kuyken Here is the data from Schönbrunn;
4 males, 3 females
I have no idea if they were victims of the illegal wildlife trade like Chester's Collared trogons, some of their native countries are hubs for traffickers.
Yes, Schönbrunn got 7, according to Zootierliste. They are kept offshow. The species bred in Lincoln Park Zoo is not the one in my picture. The collared trogons in Chester were taken from a great breeder in the Netherlands, don't be too soon to judge the wildlife trade.
@Jo Kuyken Really for Chester Zoo's Collared trogons not coming from Illegal traders like what they cited on their official website and Zootierliste saying that they were confiscated?
Yes they were confiscated from a private breeder like mentioned above, but the guy was a great breeder of many other species. I think his paperwork was even done correctly, yet the police took the animals away. From Chester's point of view, you could say they are coming from the illegal wildlife trade.