There are 71 known taxa of birds endemic to the Hawaiian Islands, of which 23 are extinct and 30 of the remaining 48 species and subspecies are listed as endangered or threatened by the U.S. Fish and Wildlife Service. Habitat loss and avian disease are thought to have had the greatest effect on endemic bird species in Hawaii. Listed below are just a few of Hawai'i's unique species of birds. Not all of them are listed.
The ‘akiapōlā‘au was fairly abundant and widely distributed on the Big Island until the 1970s. They once inhabited forests from central Kona to Hilo. Dwindling forests and competition from alien plants and animals have reduced the population to only 1,900 birds. The largest ‘akiapōlā ‘au population (about 900 birds) now lives in Hamakua; other smaller populations are at Ka‘u and Kona forests. This bird appears to favor koa forest at all locations. Scientists believe that the fragmentation and separation of the once connected Hamakua, Mauna Kea, Ka‘u, and Kona forests might have contributed to the decline in numbers. It is not known if different populations move from one area to another.
The 'Akohekohe has a distinctive, forward-sweeping white crest that gives the bird its English name, Crested Honeycreeper. The striking crest helps pollinate native plants as the bird moves from flower to flower while feeding. Threats to this unique honeycreeper include habitat destruction by human settlers and their pigs, goats, and sheep; predation by non-native cats, rats, mongooses, and Barn Owls; and mosquito-borne diseases, which have devastated native bird populations. Historically, the 'Akohekohe's unusual appearance also made it desirable to collectors. The wet, high-altitude rainforests where this species can be found are estimated to cover only 5 percent of the bird's original range. The 'Akohekohe was formerly found elsewhere on Maui, and also on the island of Moloka'i, where it is now considered extinct. 'Akohekohe maintain year-round territories around their nests or nectar sources. They are highly aggressive and territorial, chasing off native rivals such as the 'Apapane and 'I'iwi when competing for food. 'Akohekohe usually feed on 'ohi'a flower nectar, but will take nectar from other native plants, as well as insects and fruits. Their breeding season coincides with 'ohi'a bloom, and multiple broods are common, with up to three clutches per year.
Endemic to the Big Island, this crow favored the upland forests between 3,000 to 6,000 feet in elevation on Hualalai and Mauna Loa. They were most often found in ‘ōhi‘a or ‘ōhi‘a-koa forests. The ‘alalā is omnivorous, preferring fruits of native trees and shrubs, but also eating insects, mice, and sometimes the nestlings of small birds. Breeding usually occurs from March through July. The ‘alalā lays one to five greenish-blue eggs, but only two survive. The family groups stay together until the young learn to fly and eat on their own. The ‘alalā has a crow-like call: “cawk” or “ca-wak” but they also make many other sounds. Their vocalizations are more musical and varied than most other crows. Since 1973, there has been extensive research on the ‘alalā. They were once abundant in the lower forests of the western and southern sides of the island of Hawai‘i. When coffee and fruit farmers began shooting them in the 1890s, their population was already declining. By 1978, only 50 to 150 crows were believed to exist. Disease, predation by alien mammals, and loss of suitable habitat due to grazing and logging are also factors in the decline of the Hawaiian crow. The last two ‘alalā vanished from their territory in South Kona in 2002.
The Hawai‘i ‘amakihi is a small, generalist Hawaiian honeycreeper that occurs on the islands of Hawai‘i, Maui, and Moloka‘i. Until 1995, the Hawai‘i ‘amakihi, and the O‘ahu (H. flavus) and Kaua‘i ‘amakihi were considered a single species: the common ‘amakihi (H. virens). Plumage of male Hawai‘i ‘amakihi is bright yellow-green above, and there is some inter-island variation, especially among females. Both have decurved bills. They are generalized foragers that most often glean arthropods from the leaves, blossoms, twigs, branches, and less frequently from tree trucks of a variety of trees, ferns, and shrubs. They feed on nectar predominately from the flowers of ‘ōhi‘a, māmane, and native lobelias, but also forages on flowers of a number of other native and non-native plants.
The ʻApapane is found on the Big Island, Maui, Lanaʻi, Kauaʻi, Molokaʻi, and Oʻahu. More than 80 percent of the population occurs on the Big Island, where the birds live in higher-elevation ʻohiʻa forests, especially in Hawaiʻi Volcanoes National Park. There are also sizeable populations on both Maui and Kauaʻi. Molokaʻi and O‘ahu shelter healthy populations, and a small relict population exists on Lanaʻi. ‘Apapane have brush-tipped tongues adapted for sipping nectar. They rely heavily on the nectar of ‘ohi‘a flowers, and are important pollinators of this tree. The birds wander widely on their home islands, following the blooming patterns of native trees. Although ʻApapane primarily feed on nectar, the birds also consume a variety of insects. Males are well-known singers. They have at least six different calls and ten different song patterns, including a wide variety of squeaks, whistles, rasping notes, clicking sounds, and melodic trills.
The ʻelepaios are three species of monarch flycatcher in the genus Chasiempis. They are endemic to Hawaiʻi and were formerly considered conspecific. They measure 14 cm long and weigh 12–18 g. One species inhabits the Big Island, another Oʻahu and the third Kauaʻi. Being one of the most adaptable native birds of the archipelago, no subspecies have yet become extinct, though two have become quite rare. The ʻelepaio is the first native bird to sing in the morning and the last to stop singing at night; apart from whistled and chattering contact and alarm calls, it is probably best known for its song, from which derives the common name: a pleasant and rather loud warble which sounds like e-le-PAI-o or ele-PAI-o. It nests between January and June.
The ʻiʻiwi or scarlet Hawaiian honeycreeper is a "hummingbird-niched" species of Hawaiian honeycreeper. It is one of the most plentiful species of this family, many of which are endangered or extinct. The ʻiʻiwi is a highly recognizable symbol of Hawaiʻi. The ʻiʻiwi is the third most common native land bird in the Hawaiian Islands. Large colonies of ʻiʻiwi inhabit the islands of Hawaiʻi, Maui, and Kauaʻi, with smaller colonies on Molokaʻi and Oʻahu but are no longer present on Lānaʻi. Altogether, the remaining populations total 350,000 individuals, but are decreasing. The adult ʻiʻiwi is mostly scarlet, with black wings and tail and a long, curved, salmon-colored bill used primarily for drinking nectar. The contrast of the red and black plumage with surrounding green foliage makes the ʻiʻiwi one of Hawaiʻi's most easily seen birds. Younger birds have golden plumage with more spots and ivory bills and were mistaken for a different species by early naturalists. Observations of young birds moulting into adult plumage resolved this confusion.
The nene also known as nēnē and Hawaiian goose, is a species of goose endemic to the Hawaiian Islands. The official bird of the State of Hawaiʻi, the nene is exclusively found in the wild on the islands of Oahu, Maui, Kauaʻi and Hawaiʻi. By the mid 1950s Nēnē was scarce due to hunting, mongoose, dogs, and cats. In the late 50's concern mounted that the Nēnē would become extinct and efforts were undertaken to try to protect the species. The Nēnē are now making a comeback, thanks to their protected status and efforts to repopulate the species. Today the largest predator of the Nēnē are cars. It is very easy to see Nēnē on the Big Island of Hawai'i. Though you can find Nēnē in many places on the island, the largest concentration of wild birds is in and around the Hawai'i Volcanoes National Park in Volcano and on Maui Haleakala National Park.
Males have yellow underparts and head. The upperparts are duller, darker and greenish. Females are overall duller, with most of the underparts whitish. The lores, eye-ring and long decurved bill are blackish. It is 5.5 inches (14 cm) long. The last sightings - both on Kauaʻi and Maui - were in 1998, though it is possible some of the sighting in the 1990s actually involve the Kauaʻi ʻamakihi. Later sightings remain unconfirmed. Recent surveys have failed to locate any of the species and the United States Fish and Wildlife Service concluded that it in all probability are extinct or functionally extinct. As several other Hawaiian honeycreeper, the decline of the nukupuʻu group is connected to habitat loss (both due to man and hurricanes), introduced predators and disease-carrying mosquitoes.