Varied thrush

Last updated

Varied thrush
Ixoreus naevius 1.jpg
Male
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Turdidae
Genus: Ixoreus
Bonaparte, 1854
Species:
I. naevius
Binomial name
Ixoreus naevius
(Gmelin, JF, 1789)
Subspecies
  • I. n. meruloides
  • I. n. naevius
  • I. n. carlottae
  • I. n. godfreii
Ixoreus naevius map.svg
  Breeding
  Year-round
  Nonbreeding
Synonyms
  • Turdus naevius
  • Zoothera naevia

The varied thrush (Ixoreus naevius) is a member of the thrush family, Turdidae. It is the only species in the monotypic genus Ixoreus.

Contents

Taxonomy

The varied thrush was formally described by the German naturalist Johann Friedrich Gmelin in 1789 under the binomial name Turdus naevius. [2] Gmelin based his description of the "Spotted thrush" that had been described by John Latham in 1783 from specimens owned by Joseph Banks. These had been collected near Nootka Sound (formerly King George's Sound) which separates Nootka Island from Vancouver Island on the Pacific coast of Canada. [3] The varied thrush is now the only species placed in the genus Ixoreus that was introduced by Charles Lucien Bonaparte in 1854. [4] [5] The genus name Ixoreus comes from the Ancient Greek ixos meaning "mistletoe". This was a synonym of a former name for the mockingbird genus, Mimus ; Bonaparte assumed wrongly that, because William Swainson had shown a mockingbird and this thrush on the same plate of his book, they were related. The specific naevius is Latin for "spotted" from naevus meaning "spot". [6]

Four subspecies are recognised: [5]

Description

Female Ixoreus naevius -Washington, USA -female-8.jpg
Female

The varied thrush is a fairly large thrush species. It can range from 20 to 26 cm (7.9 to 10.2 in) in length and can span 34 to 42 cm (13 to 17 in) across the wings. Body mass can vary from 65 to 100 g (2.3 to 3.5 oz). Among standard measurements, the wing chord is 11.8 to 13.6 cm (4.6 to 5.4 in), the bill is 1.8 to 2.3 cm (0.71 to 0.91 in) and the tarsus is 2.9 to 3.3 cm (1.1 to 1.3 in). It is similar in size to the widespread American robin, though the varied is on average shorter with a heavier, more robust build. [7] [8] In general, varied thrushes feature intense orange and black feathers. [9] Adult males exhibit medium orange with a curved gray pattern at the breasts and throats, with grayish-blue tail ends, scruffs, and crowns. They also possess a tufted supraloral stripe and streaks of dark colors on its flight feathers. Its bill is also achromatic, but tan near the bottom of the lower jaw. Its legs are often tawny or dark brown. Females' markings are not as well-defined, with olive-browns and grays, brown hind feathers, and indiscernible gray-brown plumage near the breasts. Young varied thrushes are generally brown, though their stomach feathers are white, and initially harbor two orange stripes at the covert feathers. [10]

Eggs are generally 3–4 per nest, but sometimes 2–5. Pale blue, lightly dotted with brown. Incubation is by female, probably about 2 weeks. Young: Both parents feed nestlings. Development of young and age at which they leave the nest are not well known. Probably 2 broods per year.

There is an extremely rare variant of this species in which all the orange in the plumage is replaced by white. [11] A very rare British vagrant in 1982 was of this type, leading to speculation that whatever mutation causes the colour variation also affects the navigational abilities of this thrush. There have been only five recorded sightings since 1921. [12]

Distribution and habitat

The varied thrush breeds in western North America from Alaska to northern California. It is migratory, with northern breeders moving south within or somewhat beyond the breeding range. Other populations may only move altitudinally. This species is an improbable transatlantic vagrant, but there are now two accepted western European records, both in Great Britain, in 1982 and on Papa Westray in the Orkney Islands in October 2021. [13] [14]

Nests in Alaska, Yukon Territory, and mountains in British Columbia, Washington, and Oregon. Prefers moist conifer forest. Most common in dense, older conifer forests in high elevations. Moves to lower elevations during the winter where it is often seen in towns and orchards and thickets, or migrates to California. Seen in flocks during winter of up to 20 birds. It is well known for individual birds to fly eastward in winter, showing up in just about any state, then returning to the west coast for breeding.

Feeding

The varied thrush is predominantly insectivorous, though its diet varies throughout the course of the year. During the summer, ground-dwelling arthropods make up the bulk of its diet. During migration and winter, however, the focus of the thrush's diet shifts to fruits, seeds, and acorns, though arthropods are still taken in some quantity. Varied thrushes consume a wide variety of berries throughout the year, including snowberry, red huckleberry, California honeysuckle, madrone, salmonberry, and thimbleberry. [9]

Varied thrushes forage primarily on the ground, except when foraging for fruits and berries. [9]

Breeding

The breeding habitat is dense coniferous forest, with two to five eggs being laid in a tree nest.

Related Research Articles

<span class="mw-page-title-main">Rufous hummingbird</span> Species of bird

The rufous hummingbird is a small hummingbird, about 8 cm (3 in) long with a long, straight and slender bill. These birds are known for their extraordinary flight skills, flying 3,200 kilometres during their migratory transits. It is one of nine species in the genus Selasphorus.

<span class="mw-page-title-main">Willet</span> Species of bird

The willet is a large shorebird in the family Scolopacidae. It is a relatively large and robust sandpiper and is the largest of the species called "shanks" in the genus Tringa. Its closest relative is the lesser yellowlegs, a much smaller bird with a very different appearance apart from the fine, clear, and dense pattern of the neck, which both species show in breeding plumage. It breeds in North America and the West Indies and winters in southern North America, Central America, the West Indies and South America.

<span class="mw-page-title-main">Greater yellowlegs</span> Species of bird

The greater yellowlegs is a large shorebird in the family Scolopacidae. It breeds in central Canada and southern Alaska and winters in southern North America, Central America, the West Indies and South America.

<span class="mw-page-title-main">Lesser yellowlegs</span> Species of medium-sized shorebird

The lesser yellowlegs is a medium-sized shorebird. It breeds in the boreal forest region of North America.

<span class="mw-page-title-main">Purple finch</span> Species of bird

The purple finch is a bird in the finch family, Fringillidae. It breeds in the northern United States, southern Canada, and the west coast of North America.

<span class="mw-page-title-main">Black wheatear</span> Species of bird

The black wheatear is a wheatear, a small passerine bird in the Old World flycatcher family Muscicapidae. It is found in the Iberian Peninsula and western North Africa.

<span class="mw-page-title-main">Wood thrush</span> Species of bird

The wood thrush is a North American passerine bird in the family Turdidae and is the only species placed in the genus Hylocichla. It is closely related to other thrushes such as the American robin and is widely distributed across North America, wintering in Central America and southern Mexico. The wood thrush is the official bird of the District of Columbia.

<span class="mw-page-title-main">Swainson's thrush</span> Species of bird

Swainson's thrush, also called olive-backed thrush and russet-backed thrush is a medium-sized thrush. It is a member of genus Catharus and is typical of it in terms of its subdued coloration and beautiful, ascending flute-like voice. Swainson's thrush was named after William Swainson, an English ornithologist.

<span class="mw-page-title-main">Reed cormorant</span> Species of bird

The reed cormorant, also known as the long-tailed cormorant, is a bird in the cormorant family Phalacrocoracidae. It breeds in much of Africa south of the Sahara, and Madagascar. It is resident but undertakes some seasonal movements.

<span class="mw-page-title-main">Brahminy starling</span> Species of bird

The brahminy starling or brahminy myna is a member of the starling family of birds. It is usually seen in pairs or small flocks in open habitats on the plains of the Indian subcontinent.

<span class="mw-page-title-main">Bristle-thighed curlew</span> Species of bird

The bristle-thighed curlew is a medium-sized shorebird that breeds in Alaska and winters on tropical Pacific islands.

<span class="mw-page-title-main">Stone partridge</span> Species of bird

The stone partridge is a bird of the New World quail family. This largely brown bird, which commonly holds its tail raised, is found in scrubland and lightly wooded habitats, often near rocks, from Kenya and Ethiopia to Gambia.

<span class="mw-page-title-main">Jambu fruit dove</span> Species of bird

The jambu fruit dove is a smallish colourful fruit dove. It is a resident breeding species in southern Thailand, Malaysia, Brunei and the Indonesian islands of Kalimantan, Sumatra and Java. It is a monotypic species.

<span class="mw-page-title-main">Red-faced cormorant</span> Species of bird

The red-faced cormorant, red-faced shag or violet shag, is a bird species of the family Phalacrocoracidae.

<span class="mw-page-title-main">Capped wheatear</span> Species of bird

The capped wheatear is a small insectivorous passerine bird that is widely distributed over southern Africa. It was formerly classed as a member of the thrush family Turdidae, but is now placed in the Old World flycatcher family, Muscicapidae.

<span class="mw-page-title-main">Orange-winged pytilia</span> Species of bird

The orange-winged pytilia, also known as the golden-backed pytilia, is a species of estrildid finch found in Africa. It has a wide range and the International Union for Conservation of Nature has assessed it as being of least concern.

<span class="mw-page-title-main">Tomtit</span> Passerine bird native to New Zealand

The tomtit is a small passerine bird in the family Petroicidae, the Australasian robins. It is endemic to the islands of New Zealand, ranging across the main islands as well as several of the outlying islands. In the Māori language, the North Island tomtit is known as miromiro and the South Island tomtit is known as ngirungiru. This bird has several other Māori and English names as well. There are several subspecies showing considerable variation in plumage and size. The species is not threatened and has adapted to the changes made to New Zealand's biodiversity.

<span class="mw-page-title-main">ʻŌmaʻo</span> Species of bird

The ʻōmaʻo, also called the Hawaiian thrush, is an endemic species of robin-like bird found only on the island of Hawaii. ʻŌmaʻo are closely related to the other endemic thrushes of the Hawaiian Islands, the kāmaʻo, the olomaʻo, and the puaiohi. ʻŌmaʻo 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 near threatened.

<span class="mw-page-title-main">Dark-sided flycatcher</span> Species of bird

The dark-sided flycatcher is a small passerine bird belonging to the genus Muscicapa in the Old World flycatcher family Muscicapidae. It has a wide breeding distribution in the East Palearctic with northern birds migrating south for the winter. It is also known as the Siberian flycatcher or sooty flycatcher, the latter name is also used for the sooty flycatcher of Africa.

<span class="mw-page-title-main">Spot-backed antbird</span> Species of bird

The spot-backed antbird is a species of bird in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds". It is found in Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, and Venezuela.

References

  1. BirdLife International (2016). "Ixoreus naevius". IUCN Red List of Threatened Species . 2016: e.T22708385A94159470. doi: 10.2305/IUCN.UK.2016-3.RLTS.T22708385A94159470.en . Retrieved 12 November 2021.
  2. Gmelin, Johann Friedrich (1789). Systema naturae per regna tria naturae : secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis (in Latin). Vol. 1, Part 2 (13th ed.). Lipsiae [Leipzig]: Georg. Emanuel. Beer. pp. 817–818.
  3. Latham, John (1783). A General Synopsis of Birds. Vol. 2, Part 1. London: Printed for Leigh and Sotheby. p. 27.
  4. Bonaparte, Charles Lucien (1854). "Notes sur les collections rapportées en 1853, par M. A. Delattre, de son voyage en Californie et dans le Nicaragua". Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences. 38: 1–11, 53–67, 258–266, 378–389, 533–541, 650–665 [3].
  5. 1 2 Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (2020). "Thrushes". IOC World Bird List Version 10.2. International Ornithologists' Union. Retrieved 19 January 2021.
  6. Jobling, James A (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. pp.  208, 265. ISBN   978-1-4081-2501-4.
  7. Archived 2013-10-22 at the Wayback Machine [ permanent dead link ]
  8. Peter, Clement (2001). Thrushes. Princeton University Press. ISBN   978-0691088525.
  9. 1 2 3 George 2000, p. 1
  10. George 2000, p. 2
  11. Scott, Shirley L., ed. (1987). Field Guide to the Birds of North America (2nd ed.). National Geographic Society. p.  328. ISBN   0-87044-692-4.
  12. "Bird Walk 71 (photo gallery including photos of rare colour variant)".
  13. "Varied Thrush: new to the Western Palearctic". British Birds.
  14. "Varied Thrush: Tweet from @PapayRanger, October 2021".

Further reading