All I can say is welcome to the new normal folks. We don’t live in a Lied Jungle or Desert Dome era anymore. Most new zoo projects are smaller exhibits and nothing extraordinary or innovative, and instead are just standard new exhibits for species already in their care or new species to the zoo that can be seen everywhere else. At least in the US anyways. Rarer species are being phased out and are not looking to be obtained. The general public really doesn’t care about species that us zoo nerds fond over, and the inclusion of a sloth, llama, or kangaroo attraction is a sure way of bringing in crowds. Of course not all zoos follow this pattern. There have been exceptions and great exhibits have been built lately and some zoos like DWA are trying to keep their rarer species. Overall however, I feel most zoos are on the decline. It is my goal to see pick up all the rare species crumbs left over from a bygone era.
Sorry for being depressing, thank you for coming to my TED Talk.
I don't think most zoos are declining, I think many are changing, evolving to match with the era we live in and with the evolution of mindsets. Diversity is declining, that I agree with you.
Zoos face new challenges and they have to adapt.
The trend is not to collect as many species as you can anymore (with a few really good exceptions) and zoos have to prove their worth to people who don't know better, and they can do this by improving the quality of life of their inhabitants, by improving the looks of the exhibits and in order to do so, many zoos have to reduce the size of their collection.
Bern Tierpark aims to do so and does it very well, few species but great exhibitry.
DWA on the other hand does well at having rarities, but from the pictures I've seen, some exhibits really aren't that great and I am not sure about their breeding success with the said rarities.
Also, the EAZA doesn't support cooperation between privates and zoos from what I understood, getting new species is harder if you're not willing to work with privates who still have a great diversity in their hands. Although probably nothing like it was in the past century of course.
Then about exhibits and new projects, I can't say much about US zoos but one thing is sure : COVID hit many zoos badly and they for sure had to review their plans or delay them. But here in Europe, I am quite happy many zoos still see things big, with many interesting projects opened recently and yet to be finished. To name a few : Zürich's Pantanal is getting a net all over the area, the Elephant house in Tierpark Berlin, the Rhino house in Zoo Berlin (with part of the building already finished and looking great).