Ijima's Leaf-warbler
   HOME

TheInfoList



OR:

Ijima's leaf warbler (''Phylloscopus ijimae'') (also known as Izu leaf warbler, Ijima's willow warbler or Ijima's warbler) is a species of
Old World warbler The Old World warblers are a large group of birds formerly grouped together in the bird family Sylviidae. They are not closely related to the New World warblers. The family held over 400 species in over 70 genera, and were the source of much taxo ...
in the family
Phylloscopidae Leaf warblers are small insectivorous passerine birds belonging to the genus ''Phylloscopus''. Leaf warblers were formerly included in the Old World warbler family but are now considered to belong to the family Phylloscopidae, introduced in 2006 ...
. The species is native to
Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
, where it has been
designated Designation (from Latin ''designatio'') is the process of determining an incumbent's successor. A candidate that won an election, for example, is the ''designated'' holder of the office the candidate has been elected to, up until the candidate's ...
a
Natural Monument A natural monument is a natural or cultural feature of outstanding or unique value because of its inherent rarity, representative of aesthetic qualities, or cultural significance. They can be natural geological and geographical features such as w ...
under the 1950 Law for the Protection of Cultural Properties, with records also from Taiwan and the Philippines.


Taxonomy

Ijima's leaf warbler is a
monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...
species first described by
Leonhard Stejneger Leonhard Hess Stejneger (30 October 1851 – 28 February 1943) was a Norwegian-born American ornithologist, herpetologist and zoologist. Stejneger specialized in vertebrate natural history studies. He gained his greatest reputation with repti ...
in 1892, based on three specimens collected in the spring of 1887 by on
Miyake-jima is a Volcano, volcanic island in the Izu Islands, Izu archipelago in the Philippine Sea approximately southeast of Tokyo, Japan. As with the other islands in the Izu Island group, Miyake-jima forms part of the Fuji-Hakone-Izu National Park. ...
and
Nii-jima is a volcano, volcanic Islands of Japan, Japanese island administered by the Tokyo Metropolitan Government. It is one of the Izu Seven Islands, group of the seven northern islands of the Izu Islands, Izu archipelago, and is located approximate ...
, in the
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 Ōsh ...
of
Tokyo Tokyo, officially the Tokyo Metropolis, is the capital of Japan, capital and List of cities in Japan, most populous city in Japan. With a population of over 14 million in the city proper in 2023, it is List of largest cities, one of the most ...
. Initially given the
scientific name In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...
''Acanthopneuste ijimae'' by Stejneger, followed suit in a 1923 paper on the birds of
Izu Ōshima is an inhabited volcanic island in the Izu archipelago in the Philippine Sea, off the coast of Honshu, Japan, east of the Izu Peninsula and southwest of Bōsō Peninsula. As with the other islands in the Izu Island group, Izu Ōshima forms ...
. In a 1926 paper on a collection of birds from the
Ryūkyū Islands The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Taiwan: the Ryukyu Islands are divided into the Satsunan Islands ( Ōsumi, Tokara and Amami) and Okinawa Prefecture ( Daitō, Miyako, Y ...
, Kuroda Nagamichi treated the warbler instead as a
subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...
of the
western crowned warbler The western crowned warbler (''Phylloscopus occipitalis'') is a leaf warbler which breeds in Central Asia. It bird migration, winters in the forests of the Western Ghats. It prefers forests with high foliage complexity and tree density. The ne ...
, as ''Acanthopneuste occipitalis ijimae'', Yamashina Yoshimaro following suit in 1935. In 1938, Claud Ticehurst treated the warbler as a " race" of the
eastern crowned warbler The eastern crowned warbler (''Phylloscopus coronatus'') is a species of Old World warbler in the family Phylloscopidae. It inhabits boreal and temperate forests in the east Palearctic. Description The eastern crowned warbler is a medium-sized, ...
(''Phylloscopus coronatus''), as did
Allan Robert Phillips Allan Robert Phillips (October 25, 1914 – January 26, 1996) was an American ornithologist. He mainly studied bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, ...
in 1947, based on three specimens from the southern part of
Okinawa Island , officially , is the largest of the Okinawa Islands and the Ryukyu Islands, Ryukyu (''Nansei'') Islands of Japan in the Kyushu region. It is the smallest and least populated of the five Japanese archipelago, main islands of Japan. The island is ...
, the
combination In mathematics, a combination is a selection of items from a set that has distinct members, such that the order of selection does not matter (unlike permutations). For example, given three fruits, say an apple, an orange and a pear, there are ...
being ''Phylloscopus coronatus ijimae''. In 1953, citing differences in
songs A song is a musical composition performed by the human voice. The voice often carries the melody (a series of distinct and fixed pitches) using patterns of sound and silence. Songs have a structure, such as the common ABA form, and are usuall ...
and nesting behaviours,
Oliver L. Austin Oliver Luther Austin Jr. (May 24, 1903 – December 31, 1988) was an ornithologist who wrote the definitive study ''Birds of the World,'' eventually published in seven languages. At various times he was Director of the Austin Ornithological Resear ...
and Kuroda Nagahisa elevated the warbler to specific rank, with the
binomial Binomial may refer to: In mathematics *Binomial (polynomial), a polynomial with two terms *Binomial coefficient, numbers appearing in the expansions of powers of binomials *Binomial QMF, a perfect-reconstruction orthogonal wavelet decomposition * ...
''Phylloscopus ijimae'', a treatment followed the next year by
Charles Vaurie Charles Vaurie (7 July 1906 – 13 May 1975) was a French-born American ornithologist. He was born in Beaulieu sur Dordogne, France but moved to Trenton, New Jersey as a youth. He studied at New York University and then qualified as a dentist at ...
Kenneth Williamson Kenneth Williamson FRSE MBOU (c. 1914 – 14 June 1977) was a British ornithologist who had a strong association with Scotland and with bird migration. Life Williamson was born in Bury, Lancashire. After briefly working as a journalist, Willia ...
treated the warbler as a subspecies of the pale-legged leaf warbler, under the combination ''Phylloscopus tenellipes ijimae''; however, due to differences in its vocalizations, nesting preferences, and DNA, the warbler has again been elevated to species rank, as ''Phylloscopus ijimae''. The
specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...
honours Ijima Isao, for his contributions to Japanese ornithology.


Description

Ijima's leaf warbler 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 generally have an anisodactyl arrangement of their ...
with a total length of and weight of around . The
crown A crown is a traditional form of head adornment, or hat, worn by monarchs as a symbol of their power and dignity. A crown is often, by extension, a symbol of the monarch's government or items endorsed by it. The word itself is used, parti ...
and
nape The nape is the back of the neck. In technical anatomical/medical terminology, the nape is also called the nucha (from the Medieval Latin rendering of the Arabic , ). The corresponding adjective is ''nuchal'', as in the term ''nuchal rigidity'' ...
are a greenish-grey, upperparts a bright
olive green Olive is a dark yellowish-green color, like that of unripe or green olives. As a color word in the English language, it appears in late Middle English. Variations Olivine Olivine is the typical color of the mineral olivine. The first re ...
, flanks greyish, and underparts white. It has a long white or buffish-white
supercilium The supercilium is a plumage feature found on the heads of some bird species. It is a stripe which runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head.Dunn and Alderfer (2006), p. 10 Also k ...
, blackish eyestripe, and dark brown
iris Iris most often refers to: *Iris (anatomy), part of the eye * Iris (color), an ambiguous color term *Iris (mythology), a Greek goddess * ''Iris'' (plant), a genus of flowering plants * Iris (given name), a feminine given name, and a list of peopl ...
. The
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 pecking, grasping, and holding (in probing for food, eating, manipulating and ...
is relatively long and "broad-based", the upper
mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...
dark brown, the lower yellowish, and the legs and feet a pinkish brown. The warbler is similar in appearance to the eastern crowned warbler (''Phylloscopus coronatus''), from which it may be distinguished visually by the absence of a central stripe on its crown and by its paler yellow
undertail coverts A covert feather or tectrix on a bird is one of a set of feathers, called coverts (or ''tectrices''), which cover other feathers. The coverts help to smooth airflow over the wings and tail. Ear coverts The ear coverts are small feathers behind t ...
. Its song and calls, which include "swss, swss, swss", "swee-swee-swee-swee-swee", "shwee-it, shweet, shweet, shweet", and a soft "se-chui, se-chui, se-chui" and "phi-phi-phi", also differ from those of the eastern crowned warbler.


Distribution and habitat

Ijima's leaf warbler breeds in the summer in the
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 Ōsh ...
, from
Izu Ōshima is an inhabited volcanic island in the Izu archipelago in the Philippine Sea, off the coast of Honshu, Japan, east of the Izu Peninsula and southwest of Bōsō Peninsula. As with the other islands in the Izu Island group, Izu Ōshima forms ...
to
Aogashima is a volcanic island to the south of Japan in northernmost Micronesia. It is the southernmost and most isolated inhabited island of the Izu Islands. The islands border the northeast Philippine Sea and lie north of the Ogasawara Islands. Nussba ...
, and also on
Nakanoshima is a 3 km long and 50 hectares narrow sandbank in Kita-ku, Osaka city, Japan, that divides the Kyū-Yodo into the Tosabori and Dōjima rivers. Many governmental and commercial offices (including the city hall of Osaka), museums and oth ...
in the
Tokara Islands The is an archipelago in the Nansei Islands, and are part of the Satsunan Islands, which is in turn part of the Ryukyu Archipelago. The chain consists of twelve small islands located between Yakushima and Amami-Oshima. The islands have a total ...
. In the spring and autumn, there are records of its presence from
Honshū , historically known as , is the largest of the four main islands of Japan. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the seventh-largest island in the world, and the second-most populous after the Indonesian ...
(
Shizuoka Shizuoka can refer to: * Shizuoka Prefecture, a Japanese prefecture * Shizuoka (city), the capital city of Shizuoka Prefecture * Shizuoka Airport * Shizuoka Domain, the name from 1868 to 1871 for Sunpu Domain was a feudal domain under the Tok ...
,
Aichi is a prefecture of Japan located in the Chūbu region of Honshū. Aichi Prefecture has a population of 7,461,111 () and a geographic area of with a population density of . Aichi Prefecture borders Mie Prefecture to the west, Gifu Prefecture ...
, and
Wakayama Wakayama may refer to: * Wakayama Prefecture, a prefecture of Japan * Wakayama (city), the capital city of Wakayama Prefecture, Japan * Wakayama Station, a train station in Wakayama, Wakayama * Wakayama University, a national university in Wakayama, ...
prefectures), Mizunoko-jima,
Tanegashima is one of the Ōsumi Islands belonging to Kagoshima Prefecture, Japan. The island, in area, is the second largest of the Ōsumi Islands, and has a population of 33,000 people. Access to the island is by ferry, or by air to New Tanegashima Airp ...
,
Yakushima is one of the Ōsumi Islands in Kagoshima Prefecture, Japan. The island, in area, has a population of 13,178. It is accessible by hydrofoil ferry, car ferry, or by air to Yakushima Airport. Administratively, the island consists of the town ...
, and
Okinawa Island , officially , is the largest of the Okinawa Islands and the Ryukyu Islands, Ryukyu (''Nansei'') Islands of Japan in the Kyushu region. It is the smallest and least populated of the five Japanese archipelago, main islands of Japan. The island is ...
and the
Yaeyama Islands The Yaeyama Islands (八重山列島 ''Yaeyama-rettō'', also 八重山諸島 ''Yaeyama-shotō'', Yaeyama: ''Yaima'', Yonaguni: ''Daama'', Okinawan: ''Yeema'', Northern Ryukyuan: ''Yapema'') are an archipelago in the southwest of Okinawa Pref ...
in the
Ryūkyūs The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Geography of Taiwan, Taiwan: the Ryukyu Islands are divided into the Satsunan Islands (Ōsumi Islands, Ōsumi, Tokara Islands, Tokara and A ...
. Its wintering grounds are poorly understood; a small number may overwinter in the Izu Islands (Miyake-jima and
Hachijō-jima is a volcano, volcanic Islands of Japan, Japanese island in the Philippine Sea. It is about south of the special wards of Tokyo. It is part of the Izu Islands, Izu archipelago and within the Fuji-Hakone-Izu National Park. Its only municipalit ...
) and Ryūkyū Islands, while there are also records from Taiwan and
Luzon Luzon ( , ) is the largest and most populous List of islands in the Philippines, island in the Philippines. Located in the northern portion of the List of islands of the Philippines, Philippine archipelago, it is the economic and political ce ...
in the northern Philippines. It inhabits the "
lowland Upland and lowland are conditional descriptions of a plain based on elevation above sea level. In studies of the ecology of freshwater rivers, habitats are classified as upland or lowland. Definitions Upland and lowland are portions of a ...
deciduous In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...
and mixed
subtropical The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones immediately to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Ge ...
evergreen forest An evergreen forest is a forest made up of evergreen trees. They occur across a wide range of climatic zones, and include trees such as conifers and holly in cold climates, eucalyptus, live oak, acacias, magnolia, and banksia in more temperate zo ...
" and
laurel forest Laurel forest, also called laurisilva or laurissilva, is a type of subtropical forest found in areas with high humidity and relatively stable, mild temperatures. The forest is characterized by broadleaf tree species with evergreen, glossy and el ...
, including the
forest edge A woodland edge or forest edge is the transition zone (ecotone) from an area of woodland or forest to fields or other open spaces. Certain species of plants and animals are adapted to the forest edge, and these species are often more familiar to h ...
, stands of
alder Alders are trees of the genus ''Alnus'' in the birch family Betulaceae. The genus includes about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species ex ...
(''Alnus'') and bamboo, and
shrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominance (ecology), dominated by shrubs, often also including grasses, herbaceous plant, herbs, and geophytes. Shrubland may either occur naturally o ...
.


Ecology

Insects form the principal component of its diet — when written in
kanji are logographic Chinese characters, adapted from Chinese family of scripts, Chinese script, used in the writing of Japanese language, Japanese. They were made a major part of the Japanese writing system during the time of Old Japanese and are ...
(飯島虫喰), the warbler's Japanese name reads as "Ijima's insect-eater" — which also includes seeds. For these it forages, singly or in small groups (sometimes including other species, in particular
long-tailed tit The long-tailed tit (''Aegithalos caudatus''), also named long-tailed bushtit, is a common bird found throughout Europe and the Palearctic. The genus name ''Aegithalos'' was a term used by Aristotle for some European tits, including the long-tail ...
s (''Aegithalos caudatus'')), on lower branches, in the
forest canopy In biology, the canopy is the aboveground portion of a plant cropping or crop, formed by the collection of individual plant crowns. In forest ecology, the canopy is the upper layer or habitat zone, formed by mature tree crowns and includ ...
, and on the ground, and it may also take prey in mid-air. The breeding season is from April to June or July. Nests are built some from the ground, on
broad-leaved tree A broad-leaved, broad-leaf, or broadleaf tree is any tree within the diverse botanical group of angiosperms that has flat leaves and produces seeds inside of fruits. It is one of two general types of trees, the other being a conifer, a tree with n ...
s and in
bamboo Bamboos are a diverse group of mostly evergreen perennial plant, perennial flowering plants making up the subfamily (biology), subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family, in th ...
(this nesting behaviour differs from that of the eastern crowned warbler, which nests on the ground and in earthen
banks A bank is a financial institution that accepts deposits from the public and creates a demand deposit while simultaneously making loans. Lending activities can be directly performed by the bank or indirectly through capital markets. As banks ...
). The
clutch A clutch is a mechanical device that allows an output shaft to be disconnected from a rotating input shaft. The clutch's input shaft is typically attached to a motor, while the clutch's output shaft is connected to the mechanism that does th ...
size ranges from two to four eggs, with three or four the most common.


Conservation

The declining population, thought to total fewer than 10,000 individuals, is threatened by
habitat loss Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...
and fragmentation. In addition, the availability of prey may be impacted by the use of
pesticide Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all p ...
s. The species was badly affected by the eruption of
Miyake-jima is a Volcano, volcanic island in the Izu Islands, Izu archipelago in the Philippine Sea approximately southeast of Tokyo, Japan. As with the other islands in the Izu Island group, Miyake-jima forms part of the Fuji-Hakone-Izu National Park. ...
in 2000. With an estimated 3% of the global population, ''Phylloscopus ijimae'' ( zh, 飯島柳鶯) is included on the 2016 ''Red List of Birds of Taiwan'' with the
status Status (Latin plural: ''statūs''), is a state, condition, or situation, and may refer to: * Status (law) ** Legal status, in law ** Political status, in international law ** Small entity status, in patent law ** Status conference ** Status c ...
"vulnerable". (The species is also included on the 2016 ''Red List of China's Vertebrates'' (with the
vernacular name Vernacular is the ordinary, informal, spoken form of language, particularly when perceived as having lower social status or less prestige than standard language, which is more codified, institutionally promoted, literary, or formal. More n ...
日本冕柳莺), with the status "near threatened".) In the Philippines, the species is included on the National List of Threatened Fauna, as a migrant bird on Luzon, with the status "vulnerable". On the 2020 Japanese Ministry of the Environment
Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological sp ...
, ''Phylloscopus ijimae'' () has the status "vulnerable", as it had done also on the 1998 and 2007 editions.


See also

*
List of birds of Japan This is a list of the bird species recorded in Japan. The avifauna of Japan include a total of 731 species, of which 19 are endemic, and 31 have been introduced by humans. This list's taxonomic treatment (designation and sequence of orders, famil ...
* List of Red Lists


References


External links


BirdLife Species Factsheet
{{Taxonbar, from=Q1590370 Phylloscopus Birds described in 1892 Taxa named by Leonhard Stejneger Birds of Japan Birds of Taiwan Birds of the Philippines Natural monuments of Japan Taxonomy articles created by Polbot