- State Recognized as Endemic
- NatureServe Heritage Rank G3—Vulnerable
- IUCN Red List Ranking—Vulnerable
The O‘ahu ‘amakihi is a small, generalist Hawaiian honeycreeper (Family: Fringillidae) endemic to the island of O‘ahu. Until 1995, the O‘ahu ‘amakihi, and the Hawai‘i (C. virens) and Kaua‘i amakihi (C. stejnegeri), were considered a single species: the common ‘amakihi (C. virens). Plumage of all species is similar; males are yellow-green to olive with black lores. Females are similar, but duller. All have decurved bills. The plumage of some male O‘ahu amakihi is variable in having yellow above eyes and more yellow breasts, and compared to the other species, female O‘ahu ‘amakihi have two dull wing bars. The O‘ahu ‘amakihi is brighter and smaller than the Kaua‘i ‘amakihi. O‘ahu ‘amakihi are generalized foragers that take arthropods from a variety of trees and substrates. The species often gleans arthropods from leaves and twigs, less frequently from larger branches and trucks. Feeds on nectar and fruit from a variety of native and non-native plants and has been observed eating sap from koa (Acacia koa) trees. Only three nests have been found; thus, the species’ reproductive biology is poorly known, but is likely similar to Hawai‘i ‘amakihi.
Occurs in two separate populations between 50 and 300 meters (180 – 1,000 feet), although is most numerous above 200 meters (650 feet). In recent years, range has increased to include some residential areas. Original range likely included all forested regions of O‘ahu.
Occurs in a variety of habitats from very wet forests in the Ko‘olau Mountains to dry forests in the Wai‘anae Mountains. They are more common in sheltered forests in valleys at middle elevations. Unlike other Hawaiian passerines, the range of the O‘ahu ‘amakihi extends to low-elevation forest dominated by non-native plant species. Among introduced forests, ‘amakihi are most abundant in areas dominated by guava (Psidium guajava) or kukui (Aleurites moluccana). Most of the species’ range is managed by the U.S. Fish and Wildlife Service, U.S. Army, and the State of Hawai‘i.
Although O‘ahu ‘amakihi populations appear stable, they are likely susceptible to the same factors that threaten other native Hawaiian forest birds, including habitat loss and degradation, predation by introduced mammals, and disease. For O‘ahu ‘amakihi, the following is of particular concern:
- Fire. Non-native plants and military training activities often result in wildfires that threaten O‘ahu ‘amakihi habitat on military lands.
For more information and references visit the DLNR State Wildlife Action Plan factsheets. DOFAWʻs species pages and State Wildlife Action Plan fact sheets are provided for general information and are not meant to be a citable, original source of data. If you are a student, researcher, or writer looking for a citable source, please explore the references below or find other original data sources, rather than citing these webpages. The references below were provided by the authors of the State Wildlife Action Plan fact sheets at the time of drafting:
- IUCN Red List of Threatened Species. 2015. Version 2014.3. Available at: www.iucnredlist.org. (Accessed May 2015).
- Lindsey GD, VanderWerf EA, Baker H, Baker PE. 1998. Hawai’i (Hemignathus virens), Kaua’i (Hemignathus kauaiensis), O’ahu (Hemignathus chloris) and greater ‘amakihi (Hemignathus sagittirostris). In The Birds of North America, No. 360 (Poole A, Gill F, editors.). Philadelphia, (PA): The Academy of Natural Sciences; and Washington DC: The American Ornithologists’ Union.