Sorry PAT, missed your comment before - this was indeed a Polar Bear exhibit at the time of my first visit in 2003.
....and it is now a racoon exhibit - with a great deal of foliage in it (these rather nasty murals are invisible). The Arctic foxes are to be found in a simple, fenced paddock, nearby (and very nice it is too).
Just an update, the polar bear at the Bronx zoo died and they are not replacing him. Thank God, totally too small enclosure!
Thanks @carrie - bu you appear to be muddling the Bronx Zoo, where I believe the last Polar Bear died a while ago (and where the erstwhile Polar Bear enclosure now houses Dhole), with Brno Zoo, in the Czech Republic, where there is currently at least one Polar Bear still living.