Hawaiian Birds – Amakihi Conservation

‘Amakihi originally occurred from sea level to uppermost forested regions on all major islands, but after the arrival of humans, the clearing of native forests, and the introduction of competitors, predators, and diseases, their occupied range decreased.

The Greater ‘Amakihi, which was found only on the Big Island, became extinct early in the twentieth century. The population of the Kaua‘i ‘Amakihi (Hemignatus kauaiensis) which originally occupied the entire island of Kaua‘i, was decreasing by the 1890s as low-elevation native forests were cleared, and exotic ungulates, predators, and avian diseases were introduced. But on a positive note, the population was estimated to be 10,750 in the 1970s and increasing to more than 15,000 by the 1980s.

Mosquito-borne avian diseases were believed to prevent most native bird species from permanently residing in native forests at low elevations on most islands. Additionally, the predation on eggs, nestlings, and adults by rats, feral cats, owls is a serious threat. Even though avian malaria and avian pox are known to cause direct mortality in Hawaiian honeycreepers, some populations appear to have developed a resistance to the malaria parasite, allowing them to survive at low elevations.