Some might say the £14 entry fee is quite expensive for what you get, but I disagree, for £14 you can see the UK's only polar bears (pretty damn close if you go the feeding, they come right up to the fence) as well as plenty of other rarely exhibited species such as wolverine, musk ox, European Elk, Artic Wolves, Japanese Macaques and European Bison. Its quite a hilly place (being the HIGHLAND Wildlife Park) but for the majority of the park it is wheelchair friendly, especially the facilities like the cafe and toilets. As you enter the reserve you go through a drive-through safari bit (DO NOT GET OUT OF YOUR CAR) where there are Prezwalski's horse, yak and red deer and then you can either continue on through the drive-through reserve or park up and have a look round the walk-around part of the park. I would say for most people around 2-3 hours is suffient to comfortably see all the animals, however if like me you're a keen photographer you might find yourself staying a little longer (I was by the polar bears for 45 minutes snapping away).
The only criticism I have of the park is about the beaver. I haven't seen beaver before and was very much looking forward to seeing some, but knowing they're nocturnal animals I guessed this would be via an infra-red camera concealed in the lodge to observe them sleeping. This was not the case, however, as the ponly thing they offered was a "recent" picture of one of the beaver taken at night, which was actually dated 13/4/2013. I don't class just over two months ago as recent. I understand it costs money and might potentially disturb the beaver to fit this equipment but I think it would benefit visitors in the long run.
Also a lot of animals were off-show due to the fact they were giving birth/ raising young. Understandable being as its June, and just the excuse to come beack again.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.