Habitat
Old-growth mesic and wet koa Acacia koa and `ohi`a Metrosideros polymorpha forest between 1,300 and 2,100 m in Ka`u, Hamakua and perhaps still in Kona. It formerly occupied dry mamane and naio woodlands from 1,900 to 2,900 m on Mauna Kea.
Rarity Status
Currently this species is not classified as a rarity in this country OR information has not been updated.
Population
Estimated population is 1,200 (2010) and decreasing.
Status EN
Habitat destruction and degradation through grazing and logging (particularly of koa), predation by introduced rats, feral cats and native raptors, and avian diseases spread by introduced mosquitoes, are the main threats.
For more information see BirdLife International Species Factsheet.
Voice
Song is a short, rapid warble. Calls include an upslurred whistle, a very short warble 'cheedle-ee', and a short 'sweet'. Juveniles utter a loud 'chewp' as sound beacon to attendant adults.
Akiapolaau (Hemignathus wilsoni) [XC124801]
by Daniel Lane from Kipuka Ahiu, Northwest Fragment, Hawaii County, Hawaii, United States (song)
Akiapolaau (Hemignathus wilsoni) [XC122401]
by Brooks Rownd from Kipuka Ahiu, Powerline Road, Station 26-1, Hawaii County, Hawaii, United States (call)
Subspecies
Genus sometimes listed as Heterorhynchus, but this name is an objective synonym of current genus name. It is unclear which name published earlier, and current genus name was adopted using Principle of First Reviser.
No subspecies.
Similar Species
Hawaii Amakihi (Chlorodrepanis virens) which is similarly coloured but much smaller with proportionally smaller bill.
References
See References.