The Nihoa millerbird (Acrocephalus familiaris kingi) is a subspecies of the millerbird. It gets its name from its preferred food, the Miller moth. The 5-inch (13 cm) long millerbird has dark, sepia-colored feathers, white belly, and dark beak. Its natural geographic range is limited to the tiny island of Nihoa in the Northwestern Hawaiian Islands, and it is hoped that birds translocated to Laysan will help to ensure the survival of the species. The Nihoa millerbird is one of the two endemic birds remaining on Nihoa, the other being the Nihoa finch.

The species is CRITICALLY ENDANGERED.

Every bird listed as a potential answer is endangered/threatened.

More Info: en.wikipedia.org