Behind both thick wire AND dirty, reflective glass.

A couple of years ago, some teens stole a couple of Meerkats from their enclosure at the local Zoo. The Meerkats were found a couple of days later and returned to the Zoo.
However to prevent anyone from getting even "near" the Meerkats, heavy wire was added to the display.
Before then, waist high glass - plus a railing to keep visitors back a foot away from the glass - were the only barriers between visitors and the Meerkats.
In "the old days", the Meerkats were an extremely popular exhibit with the public.
Now, the Meerkats get no more notice than the other animals that live in totally glassed cubicles. These days, I very seldom bother myself to stop at the enclosure.

Once one of the MOST photographer friendly exhibits at the Zoo, the Meerkats are now next to impossible to photograph.
There are just too many barriers now separating them from the public. I was "lucky" to have gotten even this shot.
The light has to be "just right" and a Meerkat has to in in just the "right position" now to get any kind of photo of them. This seldom happens...
Plus you then have to shoot through either wire or glass. And at some angles, both.

The addition of the heavy wire was supposed to be only temporary. However, at this Zoo, "temporary" seems to mean "under 20 years".
I miss being able to watch and to properly photograph the Meerkats.
However, maybe things will be better again by 2031...