The ōmao (''Myadestes obscurus'', also called the Hawaiian thrush) is an

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 elsew ...

species of robin-like bird found only on the island of

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

. Ōmao are closely related to the other endemic thrushes of the

Hawaiian Islands The Hawaiian Islands ( haw, Nā Mokupuni o Hawai‘i) are an archipelago of eight major islands, several atolls, and numerous smaller islets in the North Pacific Ocean, extending some from the island of Hawaii in the south to northernmost Kur ...

, the kāmao, the olomao, and the

puaiohi The puaiohi (''Myadestes palmeri''), or small Kauai thrush, is a rare species of songbird in the Thrush (bird), thrush family, Turdidae, that is Endemism, endemic to the Hawaiian island of Kauai, Kauai. It is closely related to the other three en ...

. Ōmao are found primarily in rainforests in the eastern and southeastern regions of the Big Island. Population estimates approximate 170,000 birds, making it the most common of the Hawaiian thrushes. It appears to have a stable population, but because the entire population exists on a small range and is endemic to a single island, it is considered vulnerable.

Description

Adult thrushes (males and females are similar in appearance) are mostly nondescript, with a grayish-brown head transitioning to a pale gray below. The back and primaries are a dull olive brown. They also have whitish vents and undertail coverts. The juveniles are also similarly dull in coloration, but have pale whitish-buff spotting on the wing coverts.

Behaviour

‘Ōma’os are mostly

frugivores A frugivore is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance and ...

, but will take insects or other small invertebrates. The bird has a song that is a set of jerky liquid notes, ''whip-per-weeo-whip-per-weet''. Their many calls include a catlike rasp, a frog like croak and even a high pitched police whistle type sound. During breeding, the birds make a bulky nest in a tree or

tree fern The tree ferns are arborescent (tree-like) ferns that grow with a trunk elevating the fronds above ground level, making them trees. Many extant tree ferns are members of the order Cyatheales, to which belong the families Cyatheaceae (scaly tree ...

, laying one to three bluish eggs inside.

Habitat

The ‘ōma’o once lived on most of the land of Hawaii. Today it is restricted to the southern and eastern slopes of the island, mostly above 1,000 meters above sea level, 25 to 30 percent of its ancestral habitat. Its preferred habitat is

rainforest Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainfores ...

, but can be found in high shrublands on

Mauna Loa Mauna Loa ( or ; Hawaiian: ; en, Long Mountain) is one of five volcanoes that form the Island of Hawaii in the U.S. state of Hawaii in the Pacific Ocean. The largest subaerial volcano (as opposed to subaqueous volcanoes) in both mass and ...

. Preferred trees include the

ohia ''Metrosideros polymorpha'', the ''ōhia lehua'', is a species of flowering evergreen tree in the Myrtus, myrtle family, Myrtaceae, that is Endemism, endemic to the six largest Hawaiian Islands, islands of Hawaii, Hawaii. It is a highly variable ...

and koa. The Hawaiian thrush avoids areas with banana poka (an invasive vine). In lower elevations, it appears to be gaining a natural resistance to

avian malaria Avian malaria is a parasitic disease of birds, caused by parasite species belonging to the genera ''Plasmodium'' and '' Hemoproteus'' (phylum Apicomplexa, class Haemosporidia, family Plasmoiidae). The disease is transmitted by a dipteran vector i ...

. Threats to this species include

habitat destruction 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 ...

from housing, tourism development and farming; introduced feral animal predation (mainly rats, cats and mongoose);

invasive plant An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

encroachment; and feral livestock such as goats and pigs. The species has been aided by several conservation actions. These include the removal of pigs from several areas in the 1990s, such as

Hakalau Forest National Wildlife Refuge Hakalau Forest National Wildlife Refuge is a protected area on the Big Island of Hawaii. It is one of two units, along with the Kona Forest National Wildlife Refuge that is managed as part of the Big Island National Wildlife Refuge Complex. A ...

, and the control of rats, cats, and ungulates. The ‘ōma’o was first described to Western science in 1789 by

Gmelin Gmelin may refer to: * Gmelin's test, a chemical test * Gmelin database, a German handbook/encyclopedia of inorganic compounds initiated by Leopold Gmelin People * Carl Christian Gmelin (1762–1837), German botanist, author of ''Flora Badensis ...

References

Birdlife Species Factsheet
*''Handbook of the Birds of the World Vol 10'', Josep del Hoyo editor,

External links

*ARKiv
O'mao imagesO'mao videos, photos, and sounds
on the Internet Bird Collection {{DEFAULTSORT:Oma'o Myadestes Endemic birds of Hawaii Birds described in 1789 Taxa named by Johann Friedrich Gmelin