Starting with only 60 of those snails, Gerardo's team has since bred and released more than 100,000, one of the biggest wildlife reintroductions in history.
It also involved the reintroduction of locally extinct species like the pink pigeon and the echo parakeet, both considered vulnerable and globally threatened.
According to the Association for Zoos and Aquariums website, there are approximately 8700 species represented in zoos around the world and just 117 reintroduction programs.
KAFANOV (voice-over): In Colorado, the wolf reintroduction proposition barely passed, with most of the votes in favor of reintroduction coming from urban areas like Denver and Boulder.
Thanks to the first ever voter-mandated reintroduction of endangered wolves in U.S. history, these wolves, captured in Oregon, were set free in Colorado's wilderness last December.
So it was an appropriate and good thing to bring them into captivity, to try to breed them, have a reintroduction program, if we care about protecting biodiversity.
Mr Biden didn’t say what those measures were, but they almost certainly include the reintroduction of a ban on so-called assault weapons as well as a more comprehensive system of background checks on those purchasing guns.