"Porcupine feeding station"

Thanks @RonBurrgundy for uploading these pictures, the picture quality is incredible.

These porcupine ones have peaked my interest, is this a supervised activity? from this and other photos it seems not?

What's in the bags? hopefully long pieces of veg that don't look too much like fingers!

@Skukuza Thank you!
The feeding of the animals is not supervised but on some cages there are signs to not feed the animals. The bags of food you can buy contain peanuts and some sort of feed pellets.
I actually wondered why the porcupines didn't jump out. In the Zoo Osnabrück for example there enclousure is much more secured but they escaped recently.