As
@TeaLovingDave and
@ThylacineAlive mentioned previously, I have done two-day zoos in the best part of a day, without feeling like I had missed out anything crucial. Berlin Zoo we could have easily completed in a day, but we left the Aquarium for a second day as we wanted an in depth look at their amazing ectotherm collection. As a result, on the first day we got revisits to the bird house, Fasanerie and (of course) the primate house as well.
The closure of the carnivore house at Zoo must be noted of course, as that may well have made us require two days.
Tierpark we were very surprised we managed in a day, and this was with me locked up in a battle with a nasty illness that struck on day five of our trip*... I would definitely like to revisit Tierpark however, just to see if the Alfred Brehm does indeed make it tick over into a two day affair (I highly suspect it does).
Plzen, despite many people telling me it is a two day zoo, was a one day zoo for us, but of course this is because their entire offshow stock (almost, still a lot of mammals and herps behind the scenes) was onshow at the time. Our excursion included a wander into and around the Dinopark (where most of their juicy bird rarities are kept) and a revisit to the Rhino House (home to a lot of their formerly offshow herps), as well as a 30-45 minute offshow tour (which was incredibly rushed as far as the rodent rooms and herp room were concerned, the main area we wandered about fairly comfortably as it was so empty...!)
In April I am visiting Pairi Daiza again as part of a larger trip with three friends (two of which are other Zoochatters) through the Low Lands (Antwerp, Best, Zie-Zoo, Beekse Bergen, Duisburg, Krefeld, Burgers', Apenheul, De Paay, Ouwehands, Dolfinarium, Artis and Blijdorp are also on the docket), so I will be interested to see if we will manage it in a day. I mentioned to
@Vision in private that because they are changing so rapidly and constantly that it's basically a new zoo each time you visit! I have also noticed that, other than a few zoos where we want a specific rarity before we move on to a different collection later in the day (eg De Paay and Best), Pairi is the only place I have found myself pre-planning a route for...a testament to just how immense of a zoo it is!
Burgers' is also a two day zoo in my opinion, at least if you are an avid birder (as someone mentioned earlier in the thread, if I wanted to I would happily rock up to the Bush with a pair of binoculars and just walk around birding all day!).
Wilhelma in my opinion is not a two day zoo, although that could be because I visited around a year ago, so at a time when their flower beds were not in bloom. Even then, I'm not a massive plant nerd so I didn't spend too long in their greenhouses by the entrance...I found I had enough time to do the whole zoo AND revisit their ape house multiple times with no issues.
Cologne I just about managed in a day by the skin of my teeth, the reptile house is immense and, like Wroclaw, would easily require a couple of days if one is a keen herp-enthusiast.
Ostrava, despite what some people told me beforehand, is not a two day zoo. It is large, but very similar to Whipsnade in that it occupies a large site but has few enclosures scattered amongst the grounds. Therefore more time is spent walking TO enclosures, than actually at them.
Walsrode and Prague are also examples where I could easily see them being two day zoos, especially if you want to revisit certain areas in Walsrode to see a specific bird and once the new parrot and Australian areas open at Prague...however, once again myself and Thylo managed to do this zoo in a day without missing anything major (and without having to break rules and stay after hours........)
* = as a side note, Duisburg, Krefeld, Walsrode, Hannover, Berlin Zoo and Berlin Tierpark were done with me in top health, Leipzig Zoo, Wildpark Leipzig, our second days at both Berlins, Magdeburg, Schonebeck, Poznan Nowe, Wroclaw and Ostrava were all done with me feeling ill, and Prague, Plzen and Jihlava done with me on the road to recovery. I ended up having to skip out on Poznan Stare entirely because I couldn't manage it after a long time walking around Nowe and to and from our hotel! Anyways, there I go rambling on a tangent once again....