As there hasn't been any official review nor outlook by Berlin Tierpark itself, I just checked the website of Berlin's parliament to which the park has to report and account regularly (as they get public funding). And in fact, I did find some quite interesting and extensive document dated December 9th.
Here is some of the most relevant as well as some minor information:
-The zoo sold about the same number of daily tickets and 12% fewer annual tickets in 2021 as in 2020. So visitor numbers are likely to have dropped again (just like many other German zoos). However, overall revenue is still expected to have grown a tiny bit.
-Himalaya has been under construction since the beginning of 2021 and is scheduled for completion in Q1 2022. The cost budget of just under €5 mio is expected to be met.
-The Asia enclosure for Otters, Barbirusas and Crested Black Macaques is scheduled for completion in mid-2022. In addition to the known 4 species (the ones just mentioned as well as bantengs on the neighboring site), there should also be a didactic trail. Total budget: around €1 mio.
-African Savannah and Giraffe Trail, should enter construction phase any day now and should reach completion by fall 2022. Cost framework: Around €5.5 mio plus giraffe trail and didactic trail.
-Demolition work and contract award procedures for the elephant house have been completed. The rough part of the construction process is scheduled to start in early 2022. Completion is currently scheduled for May 2023. The cost framework of 35 million euros will probably not be met due to the current situation in the construction industry. They also plan a didactic path here.
-2022, the zoo is to receive new trash cans and additional play elements/mini playgrounds distributed throughout the park to complement the large playgrounds. In addition, the signage will be successively renewed, especially accompanying new construction projects.
-Already completed are the renovation of the sanitary facilities, modernized parking lots, and various measures for unsealing surfaces and replanting the park.
Since I was in the park last Friday, I briefly walked the relevant construction sites.
-Overall, I didn't experience very much activity anywhere.
-Around the Asia enclosure for otters etc they started opening the pavement and planting bambus as well as other plants - in quite a large radius.
-At Himalaya you can "spot" some changes but it is difficult to be sure due to the large distance (you can only look throgh fences and bare trees). I think they painted green fences/grids black and replaced some of them by large windows,while hiding some of the big frames behind wooden elements. This would also be consistent with prior projects like Brehm and monkey building. To be honest, it could also just be my interpretation. It is very difficult to see any details from the distance.
-I also peeked through fences at the Elephant Building, but I couldn't notice much development (most of it takes place or will take place on the inside anyways.
-In the monkey building, the sign for the White-faced Saki could still be found at the old place but the Saki was nowhere to be found. Apparently, they did move it to the Silvery Marmosets in the meantime. I couldn't find any Red-Backed Bearded Sakis yet, nor any sign for them. But they should soon move in with Red Howlers and Cappuchins.
-The Sifakas occupied two indoor enclosures (once a pair and once a single animal).
-Once again no luck with the wildebeests, but
a picture with a wildebeest in the snow has been posted in the German Schueling froum.
-My personal highlight were very active Barbary macaques in the snow.
-Despite very cold weather, I met quite a good number of visitors in the park. After all, it was a sunny day and the air was particularly fresh due to the snow.