Editor's Note: This account covers the 4 species of ‘Ö‘ö in the Hawaiian Islands, plus the closely-related Kioea. Future revisions of this account may provide separate coverage for each species.
This large, interesting, and diverse family of nectar-feeding honeyeaters has its center of abundance in the Australo-Papuan region and was represented in the Hawaiian Islands by 5 species: Kaua‘i ‘Ö‘ö (‘Ö‘ö ‘ä‘ä) on the island of Kaua‘i, O‘ahu ‘Ö‘ö on O‘ahu, Bishop's ‘Ö‘ö on Moloka‘i, and Hawai‘i ‘Ö‘ö and closely on Hawai‘i. The Hawai‘i ‘Ö‘ö was the first Hawaiian honey-eater discovered by westerners, described from a specimen obtained in 1779 during Captain James Cook's third voyage; the other 4 species were not known to the scientific community until the mid- to late 1800s. The O‘ahu and Hawai‘i ‘ö‘ö and the Kioea are now definitely extinct, and the Kaua‘i and Bishop's ‘ö‘ö are probably extinct.
These medium-sized to large passerines have relatively slender, sharp, slightly down-curved, dark bills and specialized tubular tongues that function as straws for sucking nectar from many structurally different species of flowers. All 4 ‘ö‘ö have black plumage with discrete bright-yellow patches and feather-tufts, and 3 have distinctive color patterns on their graduated tail feathers; the Kioea has a streaked head, neck, upper back, and underparts, a black mask through the eye, and uniformly colored brown wings, lower back, and long graduated tail. The bright-yellow ‘ö‘ö feathers were prized by early Hawaiians and used in making long flowing cloaks, opulent feather capes, ornate headdresses, and royal standards (kahili) of the kings and high chiefs, as well as numerous leis and other items. Yellow ‘ö‘ö feathers were also gathered into small, loosely tied bunches as tax payments by common people to the ruling class.
All 5 of these honeyeaters were inhabitants of undisturbed native forests. They were highly vocal, having loud, distinct, pleasant, melodious repertoires. Only the voice of the Kaua‘i ‘Ö‘ö was ever recorded, archived, and published, and it is probably the only Hawaiian honeyeater that has been heard by anyone now living. Except for the Kaua‘i ‘Ö‘ö, most of our knowledge of these species is anecdotal; 3 of the 4 ‘ö‘ö species disappeared shortly after they were described. Much of the specimen material has little or no data, and only 10 O‘ahu ‘Ö‘ö and 4 Kioea study skins are known to exist in collections. Examination of a series of specimens and attached labels has revealed some unpublished information, herein presented for the first time.
The disappearance of Hawaiian honeyeaters was not well documented, but possible causes have been widely discussed. With the exception of hurricanes and other severe storms, negative factors contributing directly or indirectly to their extinction were related to the activities of native Hawaiians and Caucasians since their first contact with the islands. Negative factors have included destruction and modification of native forests; introduction of nonnative mammals to the islands (rats, Indian mongoose, pigs, cattle, sheep, goats, domestic cats) and their impacts on native forest habitats, as well as directly on the birds themselves; introduction of nonnative birds and associated diseases; introduction of mosquitoes; and exploitation of the ‘ö‘ö for feathers.
We dedicate this account to our longtime friend and colleague John L. Sincock, who died in 1991 at his home in Pennsylvania. John, a Research Wildlife Biologist with the U.S. Fish and Wildlife Service, studied birds in Hawai‘i (including the Leeward Islands) from 1967 until his retirement in 1984. He pioneered research on Hawaiian forest birds, particularly on Kaua‘i, and spent thousands of hours in the Alaka‘i Swamp. He found the first Kaua‘i ‘Ö‘ö nest in 1971 and, subsequently, 2 others. Assisted by his wife, Renate, he secured the first photographs of the Kaua‘i ‘Ö‘ö on 31 May 1971. He subsequently took between 300 and 400 color and black-and-white photos and several hundred feet of color super-8 motion picture film of Kaua‘i ‘Ö‘ö in the Alaka‘i Swamp in the 1970s and made sound recordings in the early 1980s. John introduced all 4 of us to the Alaka‘i Swamp, enabling us to personally observe and hear what is believed to have been the last Kaua‘i ‘Ö‘ö. We rely on much of his unpublished data in this paper.
In this account, if a species is not listed under a given topic, no information is known to exist on that subject for that species. Nouns in the Hawaiian language are both singular and plural. For museum abbreviations, see Appendix 1 .