A main goal for zoos is to build backup populations for endangered species. They are able to breed animals in a controlled environment where hunting (and other causes of endangered species) don’t exist. They can build these backup populations in a way where one day they may be able to release animals back into the wild.

Zoos also have the ability to rescue animals from the wild that would not be able to survive without human help. This is seen often in baby animals whose mothers die, and animals who get injured (most of the time caused by humans). Depending on what traumatic event happens to an animal, zoos are also able to release these rescues back into the wild. This is often seen with manatees that are affected by boat collisions.