Bonin Grosbeak
Encyclopedia
The Bonin Grosbeak or Bonin Islands Grosbeak (Chaunoproctus ferreorostris) is an extinct finch
, the only species of the genus
Chaunoproctus. It is one of the diverse bird taxa that are vernacularly called "grosbeak
s", but it is not closely related to the grosbeaks sensu stricto
. It was a retiring, although not shy bird, and was usually found singly or in pairs. It fed on fruits and buds which were primarily picked up from the ground or low shrubs; it rarely was observed to perch in trees, being apparently rather phlegmatic and somewhat reluctant to fly. Only one kind of vocalization has been described: a soft, pure and high note, sometimes short, sometimes drawn out; sometimes given singly, sometimes in a short series.
It was found only on Chichi-jima
in the Ogasawara Islands
. While reports that it was also found on Haha-jima
are almost certainly erroneous, it might have occurred on Anijima and Otōtojima. Chichi-jima is the only place, however, where the bird was observed. Several specimens were taken; some 10 remain at present. Contemporary illustrations show considerable differences, especially in males. Whether these are due to seasonal variation or whether several subspecies or even species existed could only be determined by a thorough review of the available material.
Pacific expedition, which collected 2 specimens on Chichi-jima in 1827. The following year, Kittlitz took several more specimens, but he only gave the locality "Boninsima" (="Bonin-shima": Ogasawara Islands). Following the report of two shipwrecked sailors, picked up by Beechey, that the island would make a good stopover station for whaler
s, settlement was begun in 1830.
When the Rodgers
-Ringgold
North Pacific Exploring and Surveying Expedition
called at Chichi-jima in 1854, naturalist William Stimpson
could not find the birds. What he did find, however, were rats and feral goats, sheep, dogs and cats, in addition to the pigs that were already present in 1828 (and which might have been left there by Beechey to provision future castaways). Just like the Bonin Thrush
, the Bonin Grosbeak probably succumbed soon after 1830 to habitat destruction and predation by the introduced mammals.
The collector A. P. Holst was told by settlers on Chichi-jima in 1889 that some birds had persisted on Haha-jima until the early 1880s. However, given that the species was not reported from there neither during the 1853 visit of the first Perry
mission to Japan
nor in 1854, this seems either erroneous or a misunderstanding for some other island in the Chichi-jima group. The sedentary habits of the Bonin Grosbeak make it unlikely that it was present anywhere outside the Chichijima Rettō.
Finch
The true finches are passerine birds in the family Fringillidae. They are predominantly seed-eating songbirds. Most are native to the Northern Hemisphere, but one subfamily is endemic to the Neotropics, one to the Hawaiian Islands, and one subfamily – monotypic at genus level – is found...
, the only species of the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Chaunoproctus. It is one of the diverse bird taxa that are vernacularly called "grosbeak
Grosbeak
Grosbeak is a form taxon containing several species of seed-eating passerine birds with large beaks. Although they all belong to the superfamily Passeroidea, they are not a natural group but rather a polyphyletic assemblage of distantly related songbirds....
s", but it is not closely related to the grosbeaks sensu stricto
Coccothraustes
Coccothraustes is a genus of large finches containing three species:* Hawfinch – Coccothraustes coccothraustes* Evening Grosbeak – Coccothraustes vespertinus* Hooded Grosbeak – Coccothraustes abeillei...
. It was a retiring, although not shy bird, and was usually found singly or in pairs. It fed on fruits and buds which were primarily picked up from the ground or low shrubs; it rarely was observed to perch in trees, being apparently rather phlegmatic and somewhat reluctant to fly. Only one kind of vocalization has been described: a soft, pure and high note, sometimes short, sometimes drawn out; sometimes given singly, sometimes in a short series.
It was found only on Chichi-jima
Chichi-jima
, formerly known as Peel Island and in the 19th century known to the English as part of the Bonin Islands, is the largest island in the Ogasawara archipelago. Chichi-jima is approximately 150 miles north of Iwo Jima. The island is within the political boundaries of Ogasawara Town, Ogasawara...
in the Ogasawara Islands
Ogasawara Islands
The Bonin Islands, known in Japan as the are an archipelago of over 30 subtropical and tropical islands, some directly south of Tokyo, Japan. Administratively, they are part of Ogasawara Municipality of Ogasawara Subprefecture, Tokyo...
. While reports that it was also found on Haha-jima
Haha-jima
is the second-largest island of the Ogasawara Islands or Bonin Islands south of the Japanese main island chain. It is about 21 km² in area.The highest points are Mt. Chibusa , approximately 462m, and Mt. Sakaigatake , 443m. The largest island of the group, Chichi-jima is approximately...
are almost certainly erroneous, it might have occurred on Anijima and Otōtojima. Chichi-jima is the only place, however, where the bird was observed. Several specimens were taken; some 10 remain at present. Contemporary illustrations show considerable differences, especially in males. Whether these are due to seasonal variation or whether several subspecies or even species existed could only be determined by a thorough review of the available material.
Extinction
The Bonin Grosbeak was discovered by the BeecheyFrederick William Beechey
Frederick William Beechey was an English naval officer and geographer. He was the son of Sir William Beechey, RA., and was born in London.-Career:...
Pacific expedition, which collected 2 specimens on Chichi-jima in 1827. The following year, Kittlitz took several more specimens, but he only gave the locality "Boninsima" (="Bonin-shima": Ogasawara Islands). Following the report of two shipwrecked sailors, picked up by Beechey, that the island would make a good stopover station for whaler
Whaler
A whaler is a specialized ship, designed for whaling, the catching and/or processing of whales. The former included the whale catcher, a steam or diesel-driven vessel with a harpoon gun mounted at its bows. The latter included such vessels as the sail or steam-driven whaleship of the 16th to early...
s, settlement was begun in 1830.
When the Rodgers
John Rodgers (naval officer, Civil War)
John Rodgers was an admiral in the United States Navy.-Early life and career:Rodgers, a son of Commodore John Rodgers, was born near Havre de Grace, Maryland. He received his appointment as a Midshipman in the Navy on 18 April 1828...
-Ringgold
Cadwalader Ringgold
Cadwalader Ringgold was an officer in the United States Navy who served in the United States Exploring Expedition, later headed an expedition to the Northwest and, after initially retiring, returned to service during the Civil War....
North Pacific Exploring and Surveying Expedition
North Pacific Exploring and Surveying Expedition
The North Pacific Exploring and Surveying Expedition, also known as the Rodgers-Ringgold Expedition was a United States scientific and exploring project from 1853 to 1856....
called at Chichi-jima in 1854, naturalist William Stimpson
William Stimpson
William Stimpson was a noted American scientist.- Biography :Stimpson was born in Boston, Massachusetts to Herbert Hathorne Stimpson and Mary Ann Devereau Brewer. The Stimpsons were of the old colonial and Revolutionary stock of Massachusetts, the earliest known member of the family being James...
could not find the birds. What he did find, however, were rats and feral goats, sheep, dogs and cats, in addition to the pigs that were already present in 1828 (and which might have been left there by Beechey to provision future castaways). Just like the Bonin Thrush
Bonin Thrush
The Bonin Thrush, Bonin Islands Thrush or Kittlitz's Thrush is sometimes separated as the only species of the genus Cichlopasser. It is an extinct species of Asian thrush...
, the Bonin Grosbeak probably succumbed soon after 1830 to habitat destruction and predation by the introduced mammals.
The collector A. P. Holst was told by settlers on Chichi-jima in 1889 that some birds had persisted on Haha-jima until the early 1880s. However, given that the species was not reported from there neither during the 1853 visit of the first Perry
Matthew Perry (naval officer)
Matthew Calbraith Perry was the Commodore of the U.S. Navy and served commanding a number of US naval ships. He served several wars, most notably in the Mexican-American War and the War of 1812. He played a leading role in the opening of Japan to the West with the Convention of Kanagawa in 1854...
mission to Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
nor in 1854, this seems either erroneous or a misunderstanding for some other island in the Chichi-jima group. The sedentary habits of the Bonin Grosbeak make it unlikely that it was present anywhere outside the Chichijima Rettō.
External links
- 3D view of specimens RMNH 90732 and RMNH 90733 at NaturalisNaturalisNaturalis is the national natural history museum of the Netherlands, based in Leiden. It originated from the merger of the Rijksmuseum van Natuurlijke Historie and the Rijksmuseum van Geologie en Mineralogie in 1984. In 1986 it was decided that the museum had to become a public museum and a new...
, Leiden (requires QuickTimeQuickTimeQuickTime is an extensible proprietary multimedia framework developed by Apple Inc., capable of handling various formats of digital video, picture, sound, panoramic images, and interactivity. The classic version of QuickTime is available for Windows XP and later, as well as Mac OS X Leopard and...
browser plugin).