What is the central idea of "Excerpt From What Zoo Critics Don't Understand"?

The main idea is that not every zoo has to be bad for an animal, many zoos in the world save the species while in the "wilderness" people kill them.

Explanation:

The other thing about the "Excerpt From What Zoo Critics Don't Understand" is that animals should belong to the wilderness, not to the limited spaces. As the planet is being destroyed by humans, the only wild places on the Erth are Antarctic and Amazonia, and maybe some parts of Africa.

The idea of the excerpt is to show how animals also confront many problems, such as poacher and hunger, and that the main reason for this is the man.