INTRODUCTION

The Hawaiian Archipelago, located more than tion by introduced mammals, particularly the cat 4000 km from the nearest continent and 3000 (Felis catus), black and Norway (&s rat- km north of the Marquesas, the nearest high is- tus and R. norvegicus),and the mongoose (Her- lands, is the worlds’ most isolated group of is- pestes auropunctatus) (Perkins 1903, Atkinson lands (Fig. 1). As a result, the Hawaiian flora and 1977), and perhaps gene pool impoverishment fauna, derived from a relatively small number due to reduced populations (Zimmerman 1948, of colonists, have a high degree of endemism and Sincock et al. 1984). Inimical factors continue to are rather vulnerable to disturbance. Many threaten the endemic biota, and today entire groups, notably Hawaiian honeycreepers (Dre- communities are threatened with . An panidinae), lobeliads (Lobeliaceae), pomace flies air of urgency thus surrounds studies of the (Drosophilidae), and land snails (Achatinellidae, Hawaiian avifauna. Amastridae, and others), offer outstanding ex- The study of the Hawaiian avifauna has amples of adaptive radiation. spanned three phases. The first was a descriptive The stimulating evolutionary insights provid- and exploratory phase that began with the ed by Hawaiian plants and are tempered Hawaiians who named the they encoun- by the bleak prospects for their continued sur- tered. This phase intensified with the arrival of vival. The ecological consequences of their re- Cook in 1778. Eleven taxa of were de- markable adaptation to the isolated Hawaiian scribed from specimens collected during Cooks’ environment have been severe. Native plants and visit to and (Medway 198 1). Col- animals have been ravaged by anthropogenic ac- lection and description of new species continued tivity since Polynesians arrived ca. 400 A.D. with the work of Bloxam, Townsend, and Deppe (Kirch 1982). Recent finds (Olson and during the early 19th century (Wilson and Evans James 1982a, 1982b) indicate that over 40 species 1890-1899). Many new species were collected of birds became extinct between Polynesian con- by Pickering and Peale (Peale 1848) during the tact and the landing of Captain Cook in 1778, Wilkes Expedition of 1838-1842. The first reli- including an entire group of large, flightless geese, able listings of the birds of the Hawaiian Islands at least eight rails, and a constellation of lowland were by Dole (1869, 1879). dry habitat . In the 200 years since Ornithological interest in the islands increased Western contact, an additional 20 species and dramatically in the second phase, beginning with subspecies of birds appear to have been extir- the last two decades of the 19th century, when pated, and 31 taxa have become endangered or most taxa were described. The tum-of-the-cen- threatened (Table 1; U.S. Fish and Wildlife Ser- tury era significantly increased our understand- vice 1983). The greatest concentration of endan- ing of the Hawaiian avifauna at a time when gered birds in the world occurs in the Hawaiian birds were apparently declining rapidly in num- Islands; they represent 7% of the taxa on the bers. Wilson made extensive collections during International Council for Preservation list 1887-1888 and described the avifauna in his (Ring 1978). classic tome Aves Hawaiienses: The Birds of the The reasons for these lossesare numerous. With Sandwich Islands (Wilson and Evans 1890- the Polynesians came the (Rat&s 1899). Wilsons’ efforts were followed by the ma- exulans), the pig (Su.sscrofa), and the dog (Canis jor collecting expeditions of Palmer in 1890-l 892 1 familiaris). Early Hawaiians probably hunted a and Perkins in 1892-1894 and 1895-1897. Re- large number of flightless birds to extinction and lying on Palmers’ collections, Baron Rothschild essentially eliminated lowland forests and wood- (1893-l 900) produced three lavishly illustrated lands by burning and clearing for agriculture volumes entitled The Avzjkuna of Luysan and (Barrau 196 1, Kirch 1982). Subfossil bird bones the Neighbouring Islands that covered the entire interred with the charred shells of extinct land Hawaiian archipelago. Important studies and snails are the last remnants of these vanished collections by Perkins on the systematics and ecosystems (Olson and James 1982b). The ex- natural history of the native land birds, insects, tinction rate drastically increased in many taxa and molluscs culminated in the great Fauna Ha- following Western contact due to further habitat waiiensis (Sharp 1899-l 9 13, Perkins 1903). degradation by man and introduced ungulates During the early part of the 20th century, Hen- (Perkins 1903, Berger 198 l), disease (Warner shaw (1902) and W. A. Bryan (1905,1908; Bryan 1968, van Riper et al. 1982), hunting (Munro and Seale 1901) recorded many important ob- 1944), competition from introduced birds and servations on the natural history and distribution insects for food (Bank0 and Banko 1976, Berger of Hawaiian forest birds. Following this produc- 198 1, Mountainspring and Scott 1985), preda- tive era, a long period of relative dormancy en- STUDIES IN AVIAN BIOLOGY NO. 9

TABLE 1 STATUS AND DISTRIBUTION OF ENDEMIC HAWAIIAN BIRDS~

Hawaii Maui Molokai Lanai Kauai NWHI

Dark-rumped Petrel (Uau) Pterodroma phaeopygiu sandwichensis EN EN EN EN EX EN . Townsends’ (Newells)’ Shearwater (Ao) Pufjinus auricularis newelli TH TH TH ? TH Band-rumped Storm-petrel (Oeoe) Oceanodroma Castro cryptoleuca ? . . . NE Hawaiian Goose (Nene) Nesochen sandvicensis EN EN . . Hawaiian Duck (Koloa) Anus wyvilliana EN EX EX EN EN Laysan Duck Anus laysanensis EN Hawaiian Hawk (10) Buteo solitarius EN . Hawaiian () Porzana sandwichensis EX ?? . . . Porzana palmeri . . . . . EX Common Moorhen (Alae-ula) Gallinula chloropus sandvicensis EX EX EN . EN EN American Coot (Alae-keokeo) Fulica americana alai EN EN EN EN EN Black-necked Stilt (Aeo) Himantopus mexicanus knudseni EN EN EN EN EN Short-eared Owl (Pueo) Asioflammeus sandwichensis NE NE NE NE NE NE . Hawaiian Crow (Alala) Corvus hawaiiensis EN . . Millerbird Acrocephalus familiaris familiaris . EN Acrocephalus familiaris kingi . . EN Elepaio Chasiempis sandwichensis sandwichensis NE Chasiempis sandwichensis ridgwayi NE Chasiempis sandwichensis bryani NE . . Chasiempis sandwichensis gayi . NE . Chasiempis sandwichensis sclateri NE Kamao Myadestes myadestinus . EN . Amaui Myadestes oahensis . . EX . Olomao Myadestes lanaiensis EX EN EX Omao Myadestes obscurus NE . . Puaiohi (Small Kauai Thrush) Myadestes palmeri . EN . Kauai 00 (Ooaa) Moho braccatus EN Oahu 00 Moho apicalis EX . Bishops’ 00 Moho bishopi . ? EX Hawaii 00 Moho nobilis EX . . Chaetoptila angustipluma EX Laysan Telespyza cantans . EN Nihoa Finch Telespyza ultima . EN HAWAIIAN FOREST BIRDS

TABLE 1 CONTINUED

Taxa Hawaii Maui Molokai Lanai Oahu Kauai NWHI OU Psittirostrapsittacea EN EX EX EX EX EN . Palila Loxioidesbaillari EN ...... Lesser Koa-Finch RhodacanthisJlaviceps EX ...... Greater Koa-Finch Rhodacanthispalmeri EX ...... Kona Grosbeak Chloridopskona EX ...... Maui Parrotbill Pseudonestorxanthophrys EN ...... Common Amakihi Hemignathus virensvirens NE ...... Hemignathusvirens wilsoni NE NE EX? Hemignathus virenschloris . . NE . . Hemignathus virensstejnegeri . . . NE . Anianiau Hemignathusparvus . . . . NE . . . Greater Amakihi Hemignathussagittirostris EX ...... Hawaiian Akialoa Hemignathusobscurus obscurus EX ...... Hemignathusobscures lanaiensis EX Hemignathusobscurus ellisianus t...... EX . . . Kauai Akialoa Hemignathusprocerus . . . . . EN . . . Nukupuu Hemignathuslucidus affinis . . EN ...... Hemignathuslucidus Iucidus . EX . Hemignathuslucidus hanapepe . . . . EN . Akiapolaau Hemignathm munroi EN . . . Kauai Creeper Oreomystisbairdi ...... NE . . . Hawaii Creeper Oreomystismana EN ...... Maui Creeper Paroreomyzamontana newtoni . NE . . . t.. Paroreomyzamontana montana . . . . . EX . Molokai Creeper Paroreomyzaflammea . EN . . . Oahu Creeper Paroreomyzamaculata . . . . . EN . Akepa Loxopscoccineus coccineus EN . . . Loxops coccineusochraceus EN ...... Loxops coccineus rufus . . . . . EX? t.. Loxopscoccineus caeruleirostris . . . NE . Ula-ai-hawane Ciridopsanna EX ...... Iiwi Vestiariacoccinea NE NE NE EX NE NE . Hawaii Mamo Drepanispacifica EX ...... Black Mamo Drepanisfunerea EX . . Crested Honeycreeper (Akohekohe) Palmeria dolei . . EN EX ...... STUDIES IN AVIAN BIOLOGY NO. 9

TABLE 1 CONTINUED

Taxa Hawaii Maui Molokai Lanai Oahu Kauai NWHI Apapane Himatione sanguinea sanguinea NE NE NE NE NE NE ... Himatione sanguinea freethii ...... EX Poo-uli Melamprosops phaeosoma EN . Totals Extinct 11 3 5 6 7 0 3 Endangeredor threatened 13 10 7 2 5 12 4 Not endangered 8 5 4 2 5 8 0 ’ Nomenclaturefollows the 1983 A.O.U. Check-listand 35th Supplement.NE = nonendangered,TH = threatened,EN = endangered;EX = extinct;? = presentstatus uncertain; ?? = presentlyabsent, statw uncertain at Westerncontact (1778); ... = believedto beabsent at Westerncontact. sued until after World War II, relieved only by research program by C. J. Ralph to study the the noteworthy forest bird surveys of Munro behavior of native birds. This study focused on (1944). a limited number of sites and obtained a per- The third phase, the modem era, was heralded spective on seasonal and year-to-year variation by the early studies of Baldwin (1944, 1945a, lacking in our study. A manuscript describing 1945b, 1947a, 1947b) and Schwartz and Schwartz these results is in preparation. (1949). World interest in the Hawaiian avifauna Olson and James (1982a, 1982b) have was greatly stimulated by the systematic studies unearthed dozens of new fossil birds species that of Amadon (1950) and ecological studies of Bal- prompted a reassessment of the impacts of Poly- dwin (1953). Warner (1968) demonstrated the nesians on the Hawaiian avifauna. Laboratory potential role of disease in decimating Hawaiian investigations have also contributed to our un- birds. A. J. Berger and his students at the Uni- derstanding of the relations of the evolution, versity of Hawaii began in-depth studies of ecology, morphology, and physiology of native breeding biology of the Hawaiian avifauna (Ber- birds (Richards and Bock 1973; MacMillen 1974, ger 1969a, 1969b, 1969c, 1970; Berger et al. 1969; 1981; Raikow 1975, 1976, 1977; Weathers and Conant 1977; Eddinger 1969, 1970, 1972; van van Riper 1982). Riper 1972, 1973b, 197&c, 1980, 1982, 1984). Despite earlier studies, in 1976 we knew little A complete review of the Hawaiian avifauna was about the current status of most native Hawaiian written by Berger (1972) and revised in 198 1. H. forest birds, because vast areas of the islands D. Pratt (1979) provided the latest major taxo- were still ornithologically unexplored (Berger nomic revision of Hawaiian land birds. During 1972). As recently as 1973, a new of hon- the 197Os, the International Biological Program eycreeper was discovered on the island of Maui focused research efforts on the mid-elevation east (Casey and Jacobi 1974), and even by 1980 the slope of Mauna Loa; these results were reviewed nests, eggs, and young had been described for in Mueller-Dombois et al. (198 1). only 11 of 37 extant taxa (Scott et al. Interest in the Hawaiian avifauna intensified 1980). In 1976, recovery plan drafts for Hawai- during the 1960s with major efforts by U.S. Fish ian forest birds were largely statements of the and Wildlife Service biologists on literature re- need for information on the basic biology of en- view (Bank0 1980-1984, Banko and Banko dangered forest birds. 1976), the birds of the Northwestern Hawaiian The primary reason for this lack of informa- Islands (J. L. Sincock and E. Kridler, unpub. tion on Hawaiian forest birds was the difficulty data) and the birds of Kauai (Richardson and of working in most forested areas of the State. Bowles 1964, Sincock et al. 1984). The Smith- Hawaiian rainforests have been described as sonian Institution launched a major investiga- having some of the most inhospitable terrain in tion of Pacific seabirds that added tremendously the world for conducting field research (Seale to our knowledge of the Northwestern Hawaiian 1900). The difficult conditions include rainfall of, Islands (Kepler 1967, 1969; Clapp and Wood- 1O-20 m/year, continual cold drizzle for days or ward 1968; Amerson 1971; Clapp 1972; Wood- weeks on end, frequent dense fog, steep slopes, ward 1972; Ely and Clapp 1973; Amerson et al. sheer cliffs, 10-l 5 deep gulches per kilometer 1974; Fleet 1974; Clapp and Wirtz 1975; Clapp along contours in many areas, nearly impenetra- and Kridler 1977; Clapp et al. 1977). From 1976 ble vegetation, treacherous earth cracks and lava to 1982, the U.S. Forest Service funded a major tubes, and remote areas far from road access.