The warbling white-eye (''Zosterops japonicus''), also known as the Japanese white-eye and mountain white-eye, is a small

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped'), which includes more than half of all bird species. Sometimes known as perching birds, passerines are distinguished from other orders of birds by th ...

bird in the

white-eye The white-eyes are a family, Zosteropidae, of small passerine birds native to tropical, subtropical and temperate Sub-Saharan Africa, southern and eastern Asia, and Australasia. White-eyes inhabit most tropical islands in the Indian Ocean, the ...

family. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bo ...

is occasionally written ''japonica'', but this is incorrect due to the gender of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

. Its native range includes much of

East Asia East Asia is the eastern region of Asia, which is defined in both geographical and ethno-cultural terms. The modern states of East Asia include China, Japan, Mongolia, North Korea, South Korea, and Taiwan. China, North Korea, South Korea ...

, including the

Russian Far East The Russian Far East (russian: Дальний Восток России, r=Dal'niy Vostok Rossii, p=ˈdalʲnʲɪj vɐˈstok rɐˈsʲiɪ) is a region in Northeast Asia. It is the easternmost part of Russia and the Asian continent; and is admin ...

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Gui ...

Korea Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic ...

, and the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

. It has been intentionally introduced to other parts of the world as a pet and as pest control, with mixed results. As one of the native species of the Japanese islands, it has been depicted in Japanese art on numerous occasions, and historically was kept as a cage bird.

Taxonomy

The warbling white-eye was described by the ornithologists

Coenraad Jacob Temminck Coenraad Jacob Temminck (; 31 March 1778 – 30 January 1858) was a Dutch aristocrat, zoologist and museum director. Biography Coenraad Jacob Temminck was born on 31 March 1778 in Amsterdam in the Dutch Republic. From his father, Jacob Temmi ...

and

Hermann Schlegel Hermann Schlegel (10 June 1804 – 17 January 1884) was a German ornithologist, herpetologist and ichthyologist. Early life and education Schlegel was born at Altenburg, the son of a brassfounder. His father collected butterflies, which stimulate ...

in 1845 from a specimen collected in Japan. They coined the

binomial name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bo ...

''Zosterops japonicus''. The English name "Japanese white-eye" was formerly used for ''Zosterops japonicus'' and what are now the Philippine

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics ( morphology), but that can successfully interbreed. Not all specie ...

of ''Z. japonicus'' were treated as a separate

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

, the "mountain white-eye" ''Z. montanus''. A

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

study published in 2018 found that ''Z. montanus'' and several subspecies of ''Z. japonicus'' were

conspecific Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organis ...

, and they were therefore lumped together. They were placed in ''Z. japonicus'' Temminck & Schlegel, 1845 as this has priority over ''Z. montanus'' ( Bonaparte, 1850). The new English name "warbling white-eye" was introduced for the combined taxa. At the same time, several other subspecies of the former ''Z. japonicus'' were split off into their own separate species,

Swinhoe's white-eye Swinhoe's white-eye (''Zosterops simplex'') is a bird species in the white-eye family Zosteropidae. It is found in east China, Taiwan, north Vietnam, the Thai-Malay Peninsula, Sumatra and Borneo. Taxonomy Swinhoe's white-eye was formally descri ...

''Z. simplex''. There are 15 recognised

many of which are island

endemics 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 ...

: * ''Z. j. japonicus'' Temminck & Schlegel, 1845 – south

Sakhalin Sakhalin ( rus, Сахали́н, r=Sakhalín, p=səxɐˈlʲin; ja, 樺太 ''Karafuto''; zh, c=, p=Kùyèdǎo, s=库页岛, t=庫頁島; Manchu: ᠰᠠᡥᠠᠯᡳᠶᠠᠨ, ''Sahaliyan''; Orok: Бугата на̄, ''Bugata nā''; Nivkh ...

, Japan and coastal Korean Peninsula * ''Z. j. stejnegeri'' Seebohm, 1891 –

Izu Islands The are a group of volcanic islands stretching south and east from the Izu Peninsula of Honshū, Japan. Administratively, they form two towns and six villages; all part of Tokyo Prefecture. The largest is Izu Ōshima, usually called simply � ...

south to Torishima ( Nanpo Archipelago) * ''Z. j. alani'' Hartert, 1905 –

Iwo Jima Iwo Jima (, also ), known in Japan as , is one of the Japanese Volcano Islands and lies south of the Bonin Islands. Together with other islands, they form the Ogasawara Archipelago. The highest point of Iwo Jima is Mount Suribachi at high. ...

(

Volcanic Islands Geologically, a high island or volcanic island is an island of volcanic origin. The term can be used to distinguish such islands from low islands, which are formed from sedimentation or the uplifting of coral reefs (which have often formed ...

) * ''Z. j. insularis'' Ogawa, 1905 – north

Ryukyu Islands The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Taiwan: the Ōsumi, Tokara, Amami, Okinawa, and Sakishima Islands (further divided into the Miyako and Yaeyama Islands), with Yon ...

* ''Z. j. loochooensis'' Tristram, 1889 – Ryukyu Islands except northern * ''Z. j. daitoensis''

Kuroda Kuroda (written: lit. "black ricefield") is a Japanese surname. Notable people with the surname include: *, Japanese painter * Akinobu Kuroda 黒田明伸, Japanese historian * Chris Kuroda, lighting designer and operator for the band Phish and J ...

, 1923 –

Borodino Islands The Battle of Borodino (). took place near the village of Borodino on during Napoleon's invasion of Russia. The ' won the battle against the Imperial Russian Army but failed to gain a decisive victory and suffered tremendous losses. Napoleon ...

* ''Z. j. obstinatus'' Hartert, 1900 –

Ternate Ternate is a city in the Indonesian province of North Maluku and an island in the Maluku Islands. It was the ''de facto'' provincial capital of North Maluku before Sofifi on the nearby coast of Halmahera became the capital in 2010. It is off the ...

Tidore Tidore ( id, Kota Tidore Kepulauan, lit. "City of Tidore Islands") is a city, island, and archipelago in the Maluku Islands of eastern Indonesia, west of the larger island of Halmahera. Part of North Maluku Province, the city includes the island ...

Bacan Islands The Bacan Islands, formerly also known as the Bachans, Bachians, and Batchians, are a group of islands in the Moluccas in Indonesia. They are mountainous and forested, lying south of Ternate and southwest of Halmahera. The islands are administe ...

(west of Halmahera) and

Seram Island Seram (formerly spelled Ceram; also Seran or Serang) is the largest and main island of Maluku province of Indonesia, despite Ambon Island's historical importance. It is located just north of the smaller Ambon Island and a few other adjacent is ...

* ''Z. j. montanus'' ( Bonaparte, 1850) – mountains in Sumatra, Java, Bali, Lesser Sundas, Sulawesi and southern Moluccas * ''Z. j. difficilis'' (

Robinson Robinson may refer to: People and names * Robinson (name) Fictional characters * Robinson Crusoe, the main character, and title of a novel by Daniel Defoe, published in 1719 Geography * Robinson projection, a map projection used since the 1960 ...

& Kloss, 1918) –

Mount Dempo Mount Dempo is the highest stratovolcano in South Sumatra province that rises above Pasumah Plain near Pagar Alam and adjacent with Bengkulu Province. Seven craters are found around the summit. A wide lake is found at the north-west end of the ...

(south Sumatra) * ''Z. j. parkesi'' (

duPont DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in ...

, 1971) –

Palawan Palawan (), officially the Province of Palawan ( cyo, Probinsya i'ang Palawan; tl, Lalawigan ng Palawan), is an archipelagic province of the Philippines that is located in the region of Mimaropa. It is the largest province in the country in t ...

(west Philippines) * ''Z. j. whiteheadi'' (Hartert, 1903) – north

Luzon Luzon (; ) is the largest and most populous island in the Philippines. Located in the northern portion of the Philippines archipelago, it is the economic and political center of the nation, being home to the country's capital city, Manila, as ...

(north Philippines) * ''Z. j. diuatae'' ( Salomonsen, 1953) – north

Mindanao Mindanao ( ) ( Jawi: مينداناو) is the second-largest island in the Philippines, after Luzon, and seventh-most populous island in the world. Located in the southern region of the archipelago, the island is part of an island group of ...

(south Philippines) * ''Z. j. vulcani'' (Hartert, 1903) – central Mindanao (south Philippines) * ''Z. j. pectoralis'' (

Mayr Mayr is a German surname. Notable people with the surname include: * Andrea Mayr (born 1979), Austrian female long-distance runner * Ernst Mayr (1904–2005), German American evolutionary biologist * Georg Mayr (1564–1623), Bavarian Jesuit pries ...

, 1945) –

Negros Negros is the fourth largest and third most populous island in the Philippines, with a total land area of . Negros is one of the many islands of the Visayas, in the central part of the country. The predominant inhabitants of the island region a ...

(west-central Philippines) * ''Z. j. halconensis'' ( Mearns, 1907) –

Mindoro Mindoro is the seventh largest and eighth-most populous island in the Philippines. With a total land area of 10,571 km2 ( 4,082 sq.mi ) and has a population of 1,408,454 as of 2020 census. It is located off the southwestern coast of Luz ...

(northwest Philippines)

Description

The warbling white-eye is olive green on its back, from

anterior Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Th ...

to posterior, and is pale green on its underside. Its feet, legs, and bill range from black to brown.van Riper SG. (2000) "Japanese White-eye (''Zosterops japonicus'')" in ''The Birds of North America'', no. 487. A. Poole and F. Gill (Eds.). Academy of Natural Sciences, Philadelphia, and American Ornithologists' Union, Washington, D.C. It has a green forehead and a yellow throat. The white-eye has rounded wings and a long, slender bill – both of which indicate this bird to be very acrobatic. Its wings are dark brown but outlined in green. Like other white-eyes, this species exhibits the distinctive white eyering that gives it its name (''mejiro'' also meaning "white eye" in Japanese). Adults range from in length, and weigh between 9.75 and 12.75 grams.

Behavior

This bird species is rarely found on the ground. It is a very sociable species that may form

flocks Flocking is the behaviour exhibited when a group of birds, called a flock, are foraging or in flight. Computer simulations and mathematical models that have been developed to emulate the flocking behaviours of birds can also generally be applie ...

with other species, in which the birds form groups to forage during flight; white-eyes only flock with birds of other species outside of the breeding season.

Allopreening Preening is a found in birds that involves the use of the beak to position feathers, interlock feather that have become separated, clean plumage, and keep ectoparasites in check. Feathers contribute significantly to a bird's insulation, waterp ...

– the art of cleaning, grooming, and maintaining parts of the body – is extremely common. Interspecific allopreening (between different species) has been observed in captivity. While sociable, however, the white-eye typically forms

monogamous Monogamy ( ) is a form of dyadic relationship in which an individual has only one partner during their lifetime. Alternately, only one partner at any one time ( serial monogamy) — as compared to the various forms of non-monogamy (e.g., pol ...

relationships with mates – it has only one mate at any one time. Social hierarchy in a flock is established through physical displays. Some of these displays are not sex dependent, such as wing flicks exposing the underwing, wing flutters and vibrations, as well as open beak displays and beak snaps (rapid shutting of the beak to make a snapping noise). During breeding seasons, however, males establish territories via the sex-specific activity of singing loudly. Males will fend off intruders of the same species, yet will allow other species of birds to nest inside of their territory.

Nesting

Pairs of individuals, generally monogamous, choose a location for the nest between 1 and 30 meters above ground level. Construction of the nest lasts 7–10 days on average, and a variety of nesting material may be used (living and non-living); spider webs, moss,

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.A reproductive biology and natural history of the Japanese White-eye (''Zosterops japonica japonica'') in urban Oahu
Technical Report 29. Island Ecosystems. US International Biological Program. Nests tend to be cup shaped, with a diameter of 56.2 mm and a depth of 41.7 mm. The majority of nests are only used once, but some may be used up to three times in any given season.

Feeding

The species is

omnivorous An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nut ...

, living on a diet of fruit from several species of flowering plants, various types of insects, and nectar at all levels of foliage. It feeds on insects by searching the leaves of flowers and scouring tree bark for larvae. Consequences of its diet include regulation of local insect populations and dispersal of seeds; however, the white-eye's seed-dispersal ability does not seem to be significant in Hawaii.

Distribution

The warbling white-eye is found in

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the no ...

, eastern

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...

, and the northern

. Migratory populations of the bird spend winters in

Burma Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John C. Wells, Joh ...

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...

Hainan Island Hainan (, ; ) is the smallest and southernmost province of the People's Republic of China (PRC), consisting of various islands in the South China Sea. , the largest and most populous island in China,The island of Taiwan, which is slight ...

, and

Vietnam Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making ...

. The white-eye is widespread and common in Japan, considered one of the more dominant bird species.Atkins China Ltd. (1997) Route 9 Detailed Feasibility Study. Final Environmental Impact Assessment Report, 6: 49–60. In spring 2018 there were several sightings of Japanese white-eyes in Southern California, with confirmed breeding in San Diego County as of 2019. However, in 2019 the California birds were reclassified as belonging to a newly designated species,

. The dominant white-eye population in Taiwan has similarly been reassigned to Swinhoe's.

Hawaii

The warbling white-eye, originally introduced in O’ahu in 1929, has rapidly expanded its population and can now be found on every island of Hawaii; the climates of these islands range from tropical rain forests to deciduous forests.Global invasive species database atabase on the Internetbr>''Zosterops japonicus'' (bird)
Invasive Species Specialist Group, IUCN Species Survival Commission. ited 2011 March 18 After subsequent releases and natural

range expansion Colonisation or colonization is the process in biology by which a species spreads to new areas. Colonisation often refers to ''successful'' immigration where a population becomes integrated into an ecological community, having resisted initia ...

(enlargement of the area it occupies), the white-eye was determined to be the most abundant land bird on the Hawaiian Islands as early as 1987. It has become a vector for avian parasites that are now known to adversely affect populations of native birds such as Hawaiian honeycreepers, as well as spreading invasive plant species through discarded seeds.

Predators

Organisms known to prey upon native Hawaiian avian species include small mammals, like the Polynesian,

black Black is a color which results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white ha ...

, and

Norway rats The brown rat (''Rattus norvegicus''), also known as the common rat, street rat, sewer rat, wharf rat, Hanover rat, Norway rat, Norwegian rat and Parisian rat, is a widespread species of common rat. One of the largest muroids, it is a brown o ...

, and the

mongoose A mongoose is a small terrestrial carnivorous mammal belonging to the family Herpestidae. This family is currently split into two subfamilies, the Herpestinae and the Mungotinae. The Herpestinae comprises 23 living species that are native to so ...

.Fielder, PL & Kareiva, PM (1998). ''Conservation Biology: For the Coming Decade''. New York: Chapman & Hall. . . There are no documented predators of the warbling white-eye. It can only be inferred that organisms that prey on small mammals and birds in the same area as the warbling white-eye also prey on the white-eye itself.

Competitors

In its natural habitat, the warbling white-eye competes with other native passerine bird species, including those of the same genus, such as the

Bonin white-eye The Bonin white-eye (''Apalopteron familiare'') or is a small songbird endemic to the Bonin Islands (Ogasawara Islands) of Japan. It is the only species in the genus ''Apalopteron''. Its taxonomic affinities were a long-standing mystery and it ...

(''Apalopteron familiare''). In Hawaii, the warbling white-eye competes with native passerines such as the common 'amakihi, for food (such as nectar and fruit), as well as for space.Gibson L. (2000) Rules and Regulations. Federal Register, 65(75): 20760-20769. In Hawaii, the warbling white-eye has been observed visiting

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 ...

(native) floral species thought to have

coevolved In biology, coevolution occurs when two or more species reciprocally affect each other's evolution through the process of natural selection. The term sometimes is used for two traits in the same species affecting each other's evolution, as well ...

with endemic

nectarivorous In zoology, a nectarivore is an animal which derives its energy and nutrient requirements from a diet consisting mainly or exclusively of the sugar-rich nectar produced by flowering plants. Nectar as a food source presents a number of benefits a ...

avian species (those that eat nectar). This means that, over time, changes in native flowers have triggered changes in native birds that feed on the nectar of these flowers; the latter change then triggers another change in the flowers, and the whole process continues to repeat itself. The visitation of the white-eye, along with the disappearance of those endemic nectarivorous passerine bird species, suggests that the white-eye is out-competing those endemic species for the floral resource (nectar).

Conservation

Native species need normal juvenile mass and bill length to recover and persist, but for this to happen, food must be restored to former levels. There is support that an introduced bird, such as the warbling white-eye, is responsible for the food shortage. Control of the white-eye is therefore essential for the recovery of native Hawaiian birds. The determination of the status of native birds is essential; those found to be endangered could possibly benefit from the designation of critical habitat. In 1980, a program to eradicate the Indian white-eye in

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

involved mist-netting and shooting the birds, and this proved to be the most successful of the various capture methods explored.Van Way V. (1984
"The White-eyes Eradication Efforts in California"
''Proceedings of the Eleventh Vertebrate Pest Conference'' (1984), University of Nebraska. Whether eradication is feasible and applicable to other instances of invasive exotic birds is yet to be determined, but could be considered a possibility for the eradication of the warbling white-eye in the Hawaiian Islands. However, because the white eye's current ecological role is not fully understood (i.e. seed disperser, pollinator, etc.) further studies are necessary before any drastic measures are taken.

References

External links

{{Authority control

warbling white-eye The warbling white-eye (''Zosterops japonicus''), also known as the Japanese white-eye and mountain white-eye, is a small passerine bird in the white-eye family. The specific epithet is occasionally written ''japonica'', but this is incorrect du ...

Birds of East Asia

Taxa named by Hermann Schlegel Taxa named by Coenraad Jacob Temminck