Mauritius Kestrel

The Mauritius kestrel hit a low of just four known birds in 1974, making it the world's rarest bird. Habitat destruction and introduced predators had decimated the population. Conservationist Carl Jones pioneered captive breeding techniques — stealing eggs to trigger second clutches, hand-rearing chicks, and managing nest sites with fanatical precision.

By 2019, the population exceeded 400 birds in the wild. The recovery proved that even critically small populations retain enough genetic diversity to bounce back with the right support. Jones's methods have since been applied to dozens of endangered island species.