When zoos first began in this country, there was nothing wrong with going shopping for the animals that they wanted to have in their collections. Explorers would capture critters from all over the world and bring them back for Americans to gawk at. After the passage of the Endangered Species Act, that changed, and institutions now only barter or donate animals. So where do new animals come from?

Barter systems are, on the surface, very simple. When two parties each have something that the other wants, they can trade. That’s how animals move from one aquarium to another: for example, the New England Aquarium wanted to acquire some puffins, and they orchestrated a trade of 800 mackerel for a dozen puffins. They maintain a jellyfish breeding program in order to have something to trade to other institutions for the critters that they seek.

Meanwhile, zoos don’t usually barter in this way: their animal-sharing model is more like Freecycle. Zoos that need to re-home animals share the news with others, but receive nothing in return other than good karma, and maybe donations from the same or other institutions when their own collections have a gap that needs filling.

A Dozen Puffins Will Get You 800 Mackerel: Inside The Weird Economy Of Zoos [NPR]
Episode 566: The Zoo Economy [Planet Money]

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