WatchList Species Account for ‘Anianiau (Hemignatus parvus)

Qualifies for the list as a Red List Species

Photo: Jack Jeffrey

The smallest of the remaining native Hawaiian birds, the ‘Anianiau is endemic to Kauai, where it once was found throughout the island but is now confined to mountain forests above 600 m, and ranging to 1,600 m, with some occurring as low as 100 m. The present distribution represents an estimated 15% of its original range. Feeding on nectar and gleaning insects, it is found in a variety of habitats, from the dry valleys of the northwest to the interior of the Alaka’i wilderness, one of the wettest places on earth. It seems able to tolerate habitat disturbance and is found in upland forests dominated by alien plants though is most common in undisturbed native forest where the dominant trees are ‘ohi’a and koa. It occasionally forms small flocks, and small groups are common during the nonbreeding months.

Where it occurs it seems common or relatively common and the population seems stable, despite the effects of two major hurricanes since 1982. Like other Hawaiian native birds, it may fall victim to rats, cats, introduced Barn Owls, and native Short-eared Owls, with some mortality from avian malaria and avian pox, especially at the lower portions of its range. Introduced yellow jackets and ants compete with the birds for arthropod prey, and development in the Koke’e region reduces available habitat. Mosquitoes may breed as high as 1,200 m, which poses a threat to the bird, and may spread into the Alaka’i region. Efforts should be made to prevent introductions of noxious plants and animals and to eradicate those already there.