The akiapōlāau (''Hemignathus wilsoni''), pronounced ''ah-kee-ah-POH-LAH-OW'', is a species of

Hawaiian honeycreeper Hawaiian honeycreepers are a group of small, passerine birds endemic to Hawaii. They are closely related to the rosefinches in the genus ''Carpodacus'', but many species have evolved features unlike those present in any other finch. Their great ...

that is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to the

island of Hawaii Hawaii ( ; haw, Hawaii ) is the largest island in the United States, located in the state of Hawaii. It is the southeasternmost of the Hawaiian Islands, a chain of volcanic islands in the North Pacific Ocean. With an area of , it has 63% of th ...

. Its natural

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s are dry and

montane Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial ...

moist forests, and the only bird species on the island to occupy the

woodpecker Woodpeckers are part of the bird family Picidae, which also includes the piculets, wrynecks, and sapsuckers. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar, and the extreme polar regions. ...

niche Niche may refer to: Science *Developmental niche, a concept for understanding the cultural context of child development *Ecological niche, a term describing the relational position of an organism's species *Niche differentiation, in ecology, the ...

. The bird is in length, and has an unusually curved

beak The beak, bill, or rostrum is an external anatomical structure found mostly in birds, but also in turtles, non-avian dinosaurs and a few mammals. A beak is used for eating, preening, manipulating objects, killing prey, fighting, probing for foo ...

-(a

specialist species A generalist species is able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources (for example, a heterotroph with a varied diet). A specialist species can thrive only in a narrow range of env ...

). The akiapolaau is a pudgy bird which has a whitish bottom and tail, black legs, yellow chest, orangish head, black face mask and bill and gray black wings. The male's song is either a loud, short ''pit-er-ieu'' or a rapid ''warba-warba''. Its various calls include an upslurred whistle, a short ''cheedle-ee'' warble, and a short ''sweet''. Due to the recent disappearance of the Kauai nukupuu in the 1900s and the Maui nukupu u in the 1990s, leading to fears that they may be extinct, the akiapōlāau may be the last of its genus. It is the only member of the subgenus ''Heterorhynchus'', which has a woodpecker-like feeding habitat and exclusively preys on insects, in contrast to the nukupu'us, which were both insect-eaters and also hummingbird-like nectarivores''.''

Distribution

The akiapōlāau occurs mainly in

old-growth An old-growth forestalso termed primary forest, virgin forest, late seral forest, primeval forest, or first-growth forestis a forest that has attained great age without significant disturbance, and thereby exhibits unique ecological feature ...

mesic and wet

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

s in Kaū and Hamakua. Koa (''

Acacia koa ''Acacia koa'' or commonly known as koa is a species of flowering tree in the family Fabaceae. It is endemic to the Hawaiian Islands, where it is the second most common tree. The highest populations are on Hawaii, Maui and Oahu. Name The name ...

'') and ōhia lehua (''

Metrosideros polymorpha ''Metrosideros polymorpha'', the ''ōhia lehua'', is a species of flowering evergreen tree in the myrtle family, Myrtaceae, that is endemic to the six largest islands of Hawaii. It is a highly variable tree, being tall in favorable situations ...

'') are dominant

canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an ...

species in its habitat. Disease-carrying

mosquito Mosquitoes (or mosquitos) are members of a group of almost 3,600 species of small flies within the family Culicidae (from the Latin ''culex'' meaning " gnat"). The word "mosquito" (formed by ''mosca'' and diminutive ''-ito'') is Spanish for "li ...

es have restricted it to elevations of between . It formerly inhabited māmane (''Sophora chrysophylla'') -naio (''

Myoporum sandwicense ''Myoporum sandwicense'', commonly known as ''naio'', bastard sandalwood or false sandalwood is a species of flowering plant in the figwort family, Scrophulariaceae. It is a tree or shrub highly variable in its form, the size and shape of its le ...

'')

dry forests The tropical and subtropical dry broadleaf forest is a habitat type defined by the World Wide Fund for Nature and is located at tropical and subtropical latitudes. Though these forests occur in climates that are warm year-round, and may receive ...

at elevations of on Mauna Kea, but this population was

extirpated Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...

in 2002.

Diet

It feeds on insects which are found hidden within the branches of the trees, along with the nectar of flowers shaped like its bill. It also looks for invertebrates at the floor of the forest where there is a large amount of natural growth. This bird uses its long bill to peck open the bark to reach the larvae; it then uses its thin upper bill to probe out the meal and its lower bill to crush its meal.Pratt, T. K., S. G. Fancy, and C. J. Ralph (2020). Akiapolaau (''Hemignathus wilsoni''), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.akiapo.01

Breeding

Several nests of this species have been discovered, most of them only having one egg, and the rate of the egg to maturation is only fifty percent. It breeds only every other year and is therefore a slow reproducer.

Conservation and threats

''Hemignathus wilsoni'' was common in the late nineteenth and early twentieth centuries. However, after that the population was being affected by rats that ate its eggs, thus limiting the increase of the wild stock. The population broke down into four populations. The smallest is three birds, another population has only twenty birds, and the largest of the small populations a group of forty-four. The largest population contains about 1,097 birds, and the figure appears to be dropping even though it is somewhat hard to find the birds. The three bird population is especially weak. This bird is threatened from the loss of habitat, where its forests are cut down. Rats, an introduced species, attack both the food sources and the birds themselves.

Cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...

s and

dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...

s also hunt the birds. Alien plants like the strawberry guava have been upstaging the two most depended on species of trees, the koa and ohia trees.

Pig The pig (''Sus domesticus''), often called swine, hog, or domestic pig when distinguishing from other members of the genus '' Sus'', is an omnivorous, domesticated, even-toed, hoofed mammal. It is variously considered a subspecies of ''Sus ...

s create wallows which can destroy the roots of trees and cause the trees to die. These wallows also can be used by mosquitoes as a breeding ground.

Mosquito Mosquitoes (or mosquitos) are members of a group of almost 3,600 species of small flies within the family Culicidae (from the Latin ''culex'' meaning " gnat"). The word "mosquito" (formed by ''mosca'' and diminutive ''-ito'') is Spanish for "li ...

es which were introduced to the islands brought diseases that the birds are not resistant to. This bird was included on the endangered species list in 1967 because of its fragmented populations, its low numbers, low reproductive numbers and habitat loss. Some efforts being made for this species include – aggressive reforestation, trying to get a captive population, the removal of feral

ungulate Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. These include odd-toed ungulates such as horses, rhinoceroses, and tapirs; and even-toed ungulates such as cattle, pigs, giraffes, ...

s, and collecting of data about its life to help with the three other plans. Conservationists have yet to obtain the eggs of this species, which will be needed to create a breeding population in captivity. Moreover, adults will be needed to keep up what little populations are still left. It is threatened by

habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

and predation by invasive species.

References

External links