In ZOO With Predators, Argentina

It was alleged in March 2008 that hundreds of the Berlin Zoo's 23,000 animals are missing, amid allegations that they have been slaughtered, and that some tigers and leopards were sent to China to make drugs for traditional Chinese medicine. Claudia Hämmerling, a Green Party politician, said she had evidence that four Asian black bears and a hippopotamus were taken from Berlin to go to a new home, but were transported instead to Wortel in Belgium, which The Guardian reports has no zoo, but does have a slaughterhouse. The zoo's director, Bernhard Blaszkiewitz, replied that the allegations were "untruths, half-truths and lies."
• Condition of the animals
The condition of the animals varies widely, especially in zoos in countries with little or no regulations. The majority of the large non-profit and scientifically oriented institutions are working to improve their animal enclosures, although constraints like size and expense make it difficult to create ideal captive environments for some species, such as dolphins and whales.
Some critics argue that animals that live in zoos are treated as voyeuristic objects rather than living creatures, and are often driven to insanity in the transition from being free and wild to incarcerated and dependent on humans for survival.