Bonin greenfinch | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Passeriformes |
Family: | Fringillidae |
Subfamily: | Carduelinae |
Genus: | Chloris |
Species: | C. kittlitzi |
Binomial name | |
Chloris kittlitzi | |
Synonyms | |
Carduelis sinica kittlitzi Contents |
The Bonin greenfinch (Chloris kittlitzi), also known as the Ogasawara greenfinch, is a small passerine bird in the finch family Fringillidae that is endemic to the Ogasawara Islands of Japan, where it is found on the Bonin Islands and Volcano Islands. It was formerly considered a subspecies of the grey-capped greenfinch (C. sinica) and some authorities consider it as such, but a 2020 analysis found it likely to represent a distinct species that diverged from C. sinica about 1.06 million years ago, and the International Ornithological Congress now recognizes it as such, making it the eleventh endemic species in Japan (alongside the Copper pheasant (Syrmaticus soemmerringii), Okinawa rail (Hypotaenidia okinawae), Amami woodcock (Scolopax mira), Japanese green woodpecker (Picus awokera), Okinawa woodpecker (Dendrocopos noguchii), Lidth's jay (Garrulus lidthi), Bonin white-eye (Apalopteron familiare), Izu thrush (Turdus celaenops), Ryukyu robin (Larvivora komadori), and Japanese accentor (Prunella rubida)). [2] There are fewer than 400 individuals in the population and it is considered critically endangered by the Japanese government, necessitating protection. [3] [4] [5] According to the Yamashina Institute for Ornithology, as of December 2021, the Ogaswara greenfinch is Japan's most endangered bird. [6] [7]
The presence of the greenfinch on the Bonin Islands was first noted by Kittlitz at the beginning of May 1828 and reported to the Imperial Academy of Sciences in Saint Petersburg in a paper read on 28 April 1830, but he did not distinguish it from the European greenfinch, recording it under the binomial Fringilla chloris. [1] [9] The Bonin Island greenfinch was first described by Henry Seebohm in 1890, as Fringilla kittlitzi. [1] [10] Subsequently treated as a subspecies of the Oriental (or grey-capped) greenfinch, under the trinominal Carduelis sinica kittlitzi or Chloris sinica kittlitzi, a paper of 2020 recommended it again be raised to species rank, as Chloris kittlitzi, and styled the Ogasawara greenfinch. [5] The split was implemented in the IOC World Bird List update of January 2021, in recognition of the "deep genetic divergence" and "morphological differences". [3] There are three syntypes (BNHM 1898.11.1.60) collected on "Nakondo-Shima" [ja], one of the Muko-jima Islands (formerly known as the Parry Islands), on 14 June 1889 in the collection of the Natural History Museum. [5] [8] In its native Japan, the greenfinch goes by the vernacular name Ogasawara-kawarahiwa (オガサワラカワラヒワ), or Oga-hiwa (オガヒワ) for short. [11] Among the Bonin islanders, it as also sometimes known as the kuzaimon (クザイモン). [12] [13]
The Ogasawara greenfinch has a total length of around 13–14 centimetres (5.1–5.5 in) and weighs some 17.5–19.5 grams (0.62–0.69 oz). [7] [14] [15] Compared with the Oriental greenfinch, from which the species has been recently split, the wings are shorter and overall body size smaller, but the beak is longer. [5] [14] [15] In particular, compared with the Japanese greenfinch (Chloris sinica minor), the beak is "longer, deeper, and thicker". [5] [15] In males, the average wing, tail, tarsus, and culmen lengths are a little longer than in females. [15] Like the Oriental greenfinch, the Ogasawara greenfinch is an olive-green, with patches of yellow on the secondaries and tail-feathers, and a pink beak. [1] [16] Seebohm observed that, compared with the Oriental greenfinch, the Ogasawara greenfinch has less yellow, while its crown and nape are olive rather than grey or brown. [1] The males have more vibrant colours. [17]
The main breeding season is from April to June. [6] [14] Clutch sizes, of 3–4 eggs, are smaller than those of the Japanese greenfinch (3–6 eggs), though the eggs themselves are somewhat larger, weighing on average 1.99 grams (0.070 oz) as opposed to 1.8 grams (0.063 oz). [6] [15] Its diet largely comprises seeds, for which it forages both on the ground and in shrubs and trees. [14] Among preferred species are Casuarina equisetifolia (as an alien tree, this has recently been eradicated [5] ) and in particular Wikstroemia pseudoretusa ; since the seeds of the latter are considerably larger than the grass seeds that comprise the majority of the diet of the Japanese greenfinch, it is thought that the larger beak of the Ogasawara greenfinch has evolved in response. [5] [15]
The Ogasawara greenfinch is a non-migratory or resident bird endemic to the Bonin and Iwo Islands. [14] Its preferred habitat for breeding is the dry lowland forest, in particular arid evergreen shrubs with a height of less than 2 metres (6 ft 7 in), [15] and it now breeds only on the small satellite islands around Haha-jima (Mukō-jima , Ane-jima , and Imōto-jima [18] ) and South Iwo Jima. [5] [14] Previously it bred also on Muko-jima, Chichi-jima, and Haha-jima. [15] [19] Outside the breeding season, it may be found on islands beyond its breeding grounds, and it forages also in more open spaces, including agricultural land and among the grasses in the settlements of Ogasawara. [14]
Reduced numbers of the then subspecies were already reported at the end of the 1920s. [15] [19] The Ogasawara greenfinch is now extinct in the Muko-jima Islands, Chichi-jima Islands, and North Iwo Jima and Iwo Jima in the Volcano Islands. [14] In response, a Population and Habitat Viability Assessment (PHVA) has been conducted (Japan's fourth after those for the Tsushima leopard cat (Prionailurus bengalensis euptilura), Okinawa rail (Hypotaenidia okinawae), and Japanese wood pigeon (Columba janthina)). [12] As a restricted-range species, it is particularly vulnerable to extreme weather events such as typhoons and localized droughts, while the small population size threatens genetic diversity. [12] [17] The Ogasawara greenfinch only breeds on islands where there are no black rats (Rattus rattus), and the rat's presence is thought to be linked to the local extinctions. [14] Invasive brown rats (Rattus norvegicus) and feral cats (Felis catus) are also linked to predation during periods of foraging on the ground, and management of these mammal species has been recommended, alongside ex situ conservation via a captive breeding programme, to reduce the risk of extinction. [12] [14] It is estimated that the species comprises 200–400 individuals in total, with a breeding population of approximately a hundred birds around Haha-jima and a further hundred birds on South Iwo Jima. [5] [7] In 2020, the breeding population in the Haha-jima Islands was 1/10 of that twenty-five years before. [7] As a subspecies, the Ogasawara greenfinch is classed as Critically Endangered on the Ministry of the Environment Red List, [20] and has been designated a National Endangered Species under the 1992 Act on Conservation of Endangered Species of Wild Fauna and Flora. [21] [22] Extinctions amongst other local restricted-range endemics following human settlement in the nineteenth century include those of the Bonin grosbeak (Carpodacus ferreorostris ), [23] Bonin wood pigeon (Columba versicolor), [24] and Bonin nankeen night heron (Nycticorax caledonicus crassirostris). [7] [21]
Iwo Jima, now officially romanized Iōtō, is one of the Japanese Volcano Islands, which lie south of the Bonin Islands and together with them make up the Ogasawara Archipelago. Together with the Izu Islands, they make up Japan's Nanpō Islands. Although 1,200 km (750 mi) south of Tokyo on Honshu, Iwo Jima is administered as part of the Ogasawara Subprefecture of the Tokyo Metropolitan Government.
The Bonin or Ogasawara Islands are a Japanese archipelago of over 30 subtropical and tropical islands located around 1,000 kilometers (620 mi) SSE of Tokyo and 1,600 kilometers (1,000 mi) northwest of Guam. The group as a whole has a total area of 84 square kilometers (32 sq mi) but only two of the islands are permanently inhabited, Chichijima and Hahajima. Together, their population was 2560 as of 2021. Administratively, Tokyo's Ogasawara Subprefecture includes the Volcano Islands and the Self-Defense Force post on Iwo Jima. The seat of government is Chichijima.
The Volcano Islands or Iwo Islands are a group of three Japanese-governed islands in Micronesia. They lie south of the Ogasawara Islands and belong to the municipality of Ogasawara, Tokyo, Tokyo Metropolis, Japan. The islands are all active volcanoes lying atop an island arc that stretches south to the Marianas. They have an area of 32.55 square kilometres (12.57 sq mi), and a population of 380. The island of Iwo Jima in the Volcano Islands lies about 1,240 kilometres (770 mi) southeast of Miyazaki.
Ogasawara is a village in Ogasawara Subprefecture, Tokyo Metropolis, Japan, that governs the Bonin Islands, Volcano Islands, and three remote islands.
Chichijima (父島) is the largest and most populous island in the Bonin or Ogasawara Islands. Chichijima is about 240 km (150 mi) north of Iwo Jima. 23.5 km2 (9.1 sq mi) in size, the island is home to about 2120 people (2021). Connected to the mainland only by a day-long ferry that runs a few times a month, the island is nonetheless organized administratively as the seat of Ogasawara Village in the coterminous Ogasawara Subprefecture of the Tokyo Metropolitan Government. Together with the Volcano and Izu Islands, it makes up Japan's Nanpō Islands.
Hahajima, Haha Jima, or Haha-jima is the second-largest island within the Bonin or Ogasawara Islands SSE of the Japanese Home Islands. The steeply-sloped island, which is about 21 km2 (8 sq mi) in area, has a population of 440. It is part of Ogasawara Village in Ogasawara Subprefecture, which is approximately 1,000 km (620 mi) south of Tokyo, Japan.
The Ogasawara subtropical moist forests is a terrestrial ecoregion which encompasses the Ogasawara Archipelago of Japan. The Ogasawara Archipelago lies in the Pacific Ocean south of Honshu, Japan's largest island, and north of the Marianas Islands. The ecoregion includes the Bonin Islands and Volcano Islands chains. The islands are volcanic in origin, and have never been linked to a continent. They are home to distinct plants and animals including many endemic species.
The short-tailed albatross or Steller's albatross is a large rare seabird from the North Pacific. Although related to the other North Pacific albatrosses, it also exhibits behavioural and morphological links to the albatrosses of the Southern Ocean. It was described by the German naturalist Peter Simon Pallas from skins collected by Georg Wilhelm Steller. Once common, it was brought to the edge of extinction by the trade in feathers, but with protection efforts underway since the 1950s, the species is in the process of recovering with an increasing population trend. Its breeding range, however, remains small. It has been argued that the species is actually a pair of cryptic species.
The grey-capped greenfinch or Oriental greenfinch is a small passerine bird in the finch family Fringillidae that breeds in broadleaf and conifer woodlands of the East Palearctic.
Ogasawara National Park is a national park in the Ogasawara Islands, located approximately one thousand kilometres to the south of Tokyo, Japan. The park was established in 1972 within the municipality of Ogasawara, itself part of Tokyo. In 2011, the Ogasawara Islands were inscribed upon the UNESCO World Heritage List.
The Japanese murrelet or crested murrelet is a small seabird in the auk family that occurs along the remote rocky coasts and in the offshore waters of Japan, and may also be found after the breeding season as far as Sakhalin to the north and in particular off South Korea. With a small and declining population, estimated as of 2017 to total 2,500–10,000 individuals, it is the rarest alcid, and the most at risk of extinction.
The Bonin white-eye or meguro (メグロ) is a small songbird endemic to the Bonin Islands of Japan. It is the only species in the genus Apalopteron. Its taxonomic affinities were a long-standing mystery and it has been placed with the bulbuls, babblers and more recently with the honeyeaters, during which it was known as the Bonin honeyeater. Since 1995 it is known to be a white-eye in the family Zosteropidae, that is closely related to the golden white-eye of the Marianas Islands.
Ijima's leaf warbler is a species of Old World warbler in the family Phylloscopidae. The species is native to Japan, where it has been designated a Natural Monument under the 1950 Law for the Protection of Cultural Properties, with records also from Taiwan and the Philippines.
The Bonin flying fox, Bonin fruit bat, or in Japanese Ogasawara giant bat is a species of flying fox in the family Pteropodidae. It is endemic to four islands in Ogasawara Islands, Japan. Its natural habitat is subtropical forests. It is threatened by habitat loss.
North Iwo Jima, now officially North or Kita Iōtō and previously known as Santo or San Alessandro, Hooge Meeuwen Island, and North Sulfur Island, is the northernmost member of Japan's Volcano Islands. Together with the Bonin Islands, the Volcanos form the Ogasawara Archipelago and Subprefecture. Together with the Bonins and Izu Islands, they form the Nanpo Islands, all formally organized as part of the Tokyo Metropolitan Government. North Iwo Jima is located 80 kilometers (50 mi) north of Iwo Jima, 207 kilometers (129 mi) SSW of Chichijima in the Bonins, and 1,170 kilometers (730 mi) south of Tokyo on Honshu. Previously inhabited by two Japanese villages from 1898 to 1944, it is current a desert island.
Tori-shima 'Bird Island', or Izu-Torishima 'Bird Island of Izu Province') is an uninhabited Japanese island in the Pacific Ocean. The volcanic island is part of the Izu Islands.
Wikstroemia pseudoretusa is a species of flowering plant in the family Thymelaeaceae that is endemic to the Bonin Islands, Tōkyō Metropolis, Japan.
Nakōdo-jima (媒島) is an uninhabited Japanese island in the Mukojima Islands, the northernmost island group of the Bonin Islands, in the village of Ogasawara, Tokyo Metropolis. The entire island and its surrounding waters form part of Ogasawara National Park, while an area of 147 hectares including surrounding reefs forms part of the Ogaswara Islands UNESCO World Heritage Site.
Orii Hyōjirō was a Japanese specimen collector of birds and mammals. At least a hundred new species and subspecies were described based on the type specimens he collected, a 2014 review putting the total, among taxa currently recognized, at 14 species and 41 subspecies of mammal, and 6 species and 68 subspecies of bird. The 7 mammal and 10 bird taxa named in honour of "Orii of the Orient", as he came to be known, include the Ryūkyū shrew and now-extinct Daitō varied tit.
The Bonin Islands are an archipelago of over 30 subtropical and tropical islands, some 1,000 kilometres directly south of Tokyo, Japan and 1,000 miles northwest of Guam.