NPR Planet Money did an episode about how zoos acquire animals. I recommend listening to it: http://www.npr.org/sections/money/2016/09/09/493295430/episode-566

NPR Planet Money did an episode about how zoos acquire animals. I recommend listening to it: http://www.npr.org/sections/money/2016/09/09/493295430/episode-566-the-zoo-economy http://www.npr.org/sections/money/2016/09/09/493295430/episo... To put it in a nutshell, they are not allowed to buy and sell animals. Aquariums can trade animals with other aquariums but no money should change hands. Zoos depend solely on goodwill, as even trade is banned. So when an animal is born in a zoo, if they don't need it or cannot keep it, they donate it to another zoo who needs it. And if a zoo needs an animals, they put the word out that they require one and some other zoo donates them one of theirs.