Hawaii’s forests evolved for millions of years without mosquitoes, but after whaling ships introduced them in the early 1800s, they spread bird malaria to native honeycreepers that had no natural immunity, driving more than 30 species to extinction

Hawaiian honeycreepers evolved in isolation without mosquitoes for millions of years. The accidental introduction of mosquitoes in the 19th century brought avian malaria. This disease proved catastrophic, causing severe declines in native bird populations. Many honeycreeper species have since gone extinct due to this introduced pathogen. Warming climates now threaten remaining high-elevation refuges for these unique birds.