How high are the walls in the exhibit? Is there a hotwire? I ask because I watched a dingo clear a 10-12 foot fence without a hotwire several years ago.
@Rookeyper: the walls were about 9-10 feet from the feet of a human to the grass, and I didn't see any hotwire anywhere. Having said that I've noticed short black poles/stumps/bars projecting out of the grass at intervals around the base of the wall. Perhaps the base is hotwired?