The Florida panther's numbers may have gone as low as 20 animals in the 1990s. The subspecies seemed doomed despite extensive conservation efforts. Fifteen years ago, the the US Fish and Wildlife Service brought in eight females from Texas and set them loose. (Panthers don't bond as mated pairs, so you don't need as many males as females.) The Texas animals are a different subspecies, but the differences are very minor, and the hybrid kittens have proven much fitter than those produced by the severely inbred Florida cats.
So here's to a successful rescue of one of America's rarest mammals.