The true finches are small to medium-sized passerine birds in the family Fringillidae. Finches generally have stout conical bills adapted for eating seeds and nuts and often have colourful plumage. They occupy a great range of habitats where they are usually resident and do not migrate. They have a worldwide native distribution except for Australia and the polar regions. The family Fringillidae contains more than two hundred species divided into fifty genera. It includes the canaries, siskins, redpolls, serins, grosbeaks and euphonias, as well as the morphologically divergent Hawaiian honeycreepers.
Located about 2300 miles (3680 km) from the nearest continental shore, the Hawaiian Islands are the most isolated group of islands on the planet. The plant and animal life of the Hawaiian archipelago is the result of early, very infrequent colonizations of arriving species and the slow evolution of those species—in isolation from the rest of the world's flora and fauna—over a period of at least 5 million years. As a consequence, Hawai'i is home to a large number of endemic species. The radiation of species described by Charles Darwin in the Galapagos Islands which was critical to the formulation of his theory of evolution is far exceeded in the more isolated Hawaiian Islands.
The cardueline finches are a subfamily, Carduelinae, one of three subfamilies of the finch family Fringillidae, the others being the Fringillinae and the Euphoniinae. The Hawaiian honeycreepers are now included in this subfamily. Except for the Hawaiian honeycreepers which underwent adaptive radiation in Hawaii and have evolved a broad range of diets, cardueline finches are specialised seed eaters, and unlike most passerine birds, they feed their young mostly on seeds, which are regurgitated. Besides this, they differ from the other finches in some minor details of their skull. They are adept at opening seeds and clinging to stems, unlike other granivorous birds, such as sparrows and buntings, which feed mostly on fallen seeds. Some members of this subfamily are further specialised to feed on a particular type of seed, such as cones in the case of crossbills. Carduelines forage in flocks throughout the year, rather than keeping territories, and males defend their females rather than a territory or nest.
The palila is a critically endangered finch-billed species of Hawaiian honeycreeper. It has a golden-yellow head and breast, with a light belly, gray back, and greenish wings and tail. The bird has a close ecological relationship with the māmane tree, and became endangered due to destruction of the trees and accompanying dry forests. The first specimen of the palila was collected in 1876 at the Greenwell Ranch on the Big Island by Pierre Étienne Théodore Ballieu (1828–1885), who was French consul in Hawai‘i from 1869 to 1878. The type specimen is housed at the Muséum national d'histoire naturelle in Paris.
Ciridops is an extinct genus of Hawaiian honeycreeper species that occurred in prehistoric and historic times on the Hawaiian islands of Hawaii, Molokai, Kauai and Oahu. This genus was created in 1892 by Alfred Newton in an article published by the journal Nature on the basis of the ʻula-ʻai-hawane, which was named Fringilla anna by Sanford B. Dole in 1879.
The Oʻahu ʻamakihi is a species of Hawaiian honeycreeper in the family Fringillidae. The male is rich yellow below, sharply contrasted with greenish upper parts. Females are duller and have two prominent wing-bars. It has a total length of approximately 4.5 inches (11 cm). It is endemic to the island of Oʻahu in Hawaiʻi, and is likely the only surviving honeycreeper endemic to the island.
Loxops is a Hawaiian honeycreeper genus in the finch family, Fringillidae. Most of them are commonly known as ʻakepa.
The lesser koa finch is an extinct species of Hawaiian honeycreeper in the subfamily Carduelinae of the family Fringillidae. It was endemic to the island of Hawaiʻi.
The greater koa finch is an extinct species of Hawaiian honeycreeper in the subfamily Carduelinae of the family Fringillidae. It was endemic to the island of Hawaiʻi.
Telespiza is a genus of Hawaiian honeycreeper. All species in it are or were endemic to the Hawaiian Islands.
The highland finch is an extinct member of the Fringillidae and a Hawaiian honeycreeper which is known only from a few bones found in caves. It is the only member of the genus Orthiospiza. It was endemic to the high-elevation areas of Mount Haleakalā on the Hawaiian island of Maui. It has been speculated that they were pushed to extinction because of habitat loss. It is known only from fossil remains and likely became extinct before the first Europeans arrived in 1778.
The scissor-billed koa finch or scissor finch is an extinct species of Hawaiian honeycreeper in the subfamily Carduelinae of the family Fringillidae. It is known from fossils on the islands of Maui and Kauaʻi in Hawaii.
The primitive koa finch is an extinct species of Hawaiian honeycreeper in the subfamily Carduelinae of the family Fringillidae. It is known from fossils on the islands of Maui and Oʻahu in Hawaii.
The King Kong grosbeak or giant grosbeak is a prehistoric species of Hawaiian honeycreeper, that was endemic to Hawaiʻi. It had the largest beak of the three Chloridops species known to have existed. The King Kong grosbeak was described from fossils found at Barber's Point and Ulupau Head on the island of Oʻahu. It was 11 inches (28 cm) long, making it one of the largest Hawaiian honeycreepers. The osteology of the mandible strongly suggests that C. regiskongi was a sister-taxon of Rhodacanthis.
Xestospiza is an extinct genus of containing two species of Hawaiian honeycreeper with cone-shaped bills that were described on the basis of bones. They were possibly insectivores. It consists of the following:
Hawaiian honeycreepers are a group of small birds endemic to Hawaiʻi. They are members of the finch family Fringillidae, closely related to the rosefinches (Carpodacus), but many species have evolved features unlike those present in any other finch. Their great morphological diversity is the result of adaptive radiation in an insular environment. Many have been driven to extinction since the first humans arrived in Hawaii, with extinctions increasing over the last 2 centuries following European discovery of the islands, with habitat destruction and especially invasive species being the main causes.
Mohoidae, also known as the Hawaiian honeyeaters, was a family of Hawaiian species of now recently extinct, nectarivorous songbirds in the genera Moho (ʻōʻō) and Chaetoptila (kioea). These now extinct birds form their own family, representing the only complete extinction of an entire avian family in modern times, when the disputed family Turnagridae is regarded as invalid. The last surviving species in the family, the Kauai O'o, became extinct after 1987.
The Hawaiian tropical dry forests are a tropical dry broadleaf forest ecoregion in the Hawaiian Islands. They cover an area of 6,600 km2 (2,500 sq mi) on the leeward side of the main islands and the summits of Niʻihau and Kahoʻolawe. These forests are either seasonal or sclerophyllous. Annual rainfall is less than 127 cm (50 in) and may be as low as 25 cm (9.8 in); the rainy season lasts from November to March. Dominant tree species include koa, koaiʻa, ʻakoko, ʻōhiʻa lehua, lonomea, māmane, loulu, lama, olopua, wiliwili, and ʻiliahi. Endemic plant species in the dry forests include hau heleʻula, uhiuhi, and Gouania spp. The palila, a Hawaiian honeycreeper, is restricted to this type of habitat.
Koa wilt is a relatively new disease to Hawaii, discovered in 1980. Koa wilt is caused by a forma specialis of the fungus Fusarium oxysporum, which is now abundant in Hawaiian soils and infects the native Acacia koa tree, a once-dominant species in the canopy of Hawaiian forests. Fusarium oxysporum f.sp. koae is believed to have been brought into Hawaii on an ornamental acacia plant. Fusarium fungi clog the tree xylem, causing significant wilt and mortality among these beautiful and iconic Hawaiian trees.
