Several species of native forest birds across Hawaiʻi are nearly extinct, including the kiwikiu and 'ākohekohe that are found only in East Maui, whose population decreased by more than 70% in the 21st century. A primary threat is mosquito-borne diseases such as avian malaria. Attempts to relocate kiwikiu to higher elevations were unsuccessful in protecting the population as mosquitos also rose into higher elevation habitats after the 1980s.
