I have no issues with keeping animals in zoos and circuses. For the most part they are treated well, fed, groomed, looked after with the best veterinary care possible and zoos have breeding programmes to try to encourage the regeneration of endangered species. Sure, I'm against dancing bears, crazy Canadians and others who choose to keep animals in very small cages, underfed, and not properly cared for, but most zoos and circuses are not like that.
Animals however have feelings, and are wild beasts, and need to be treated with dignity and respect. In San Francisco a tiger was either let out of its enclosure, or somehow escaped and the inevitable happened when tiger met human. Condolences to the family and friends of the injured and the deceased. In Yamba, New South Wales, 420 miles north of Sydney, a small, surfing, fishing rivermouth community, an elephant in the visiting Stardust Circus, apparently turned on its keeper and crushed him, having been previously traumatised at the forced separation from other elephants. Again condolences to the family and friends of the deceased.
The point of this story is merely to remind people that although we choose to keep wild animals enclosed either for research or entertainment, we need to be mindful that they are wild, that they are capable of instantaneous action and that they will turn. They're not warm fuzzy toys or cartoon characters and people need to remember this. Kudos to animal behaviourists and those working in the animal care and welfare professions.