Tim Wong is a biologist, beekeeper, butterfly habitat volunteer, horticulturist, and naturalist. As if that wasn’t impressive enough — Wong’s love of butterflies helped repopulate a species that had completely disappeared from San Francisco. And he did it all in his backyard.

The California Pipevine Swallowtail is a butterfly that had once thrived in San Francisco but eventually vanished. After the 28-year-old Wong learned that this locally rare butterfly only feeds on one plant, the California pipevine, he was determined to revitalize their population.

The greenhouse contained all of the perfect conditions for the butterfly species to thrive. The biologist then gathered 20 pipevine swallowtail caterpillars and placed them in the outdoor enclosure. It was now time for the caterpillars to make their slow transformation to butterflies.

The caterpillars would soon form cocoons and becomes a chrysalis. In as little as two weeks, a beautiful butterfly will emerge from the chrysalis. Although, in some butterfly species, the maturation process can take up to an entire year.