Swainson's thrush (''Catharus ustulatus''), also called olive-backed thrush, russet-backed thrush, and

salmonberry ''Rubus spectabilis'', the salmonberry, is a species of bramble in the rose family Rosaceae, native to the west coast of North America from west-central Alaska to California, inland as far as Idaho. Like many other species in the genus ''Rubus' ...

bird is a medium-sized

thrush Thrush may refer to: Birds * Thrush (bird), any of the birds in the family Turdidae ** List of thrush species * Antthrushes, the Formicariidae family of birds * Dohrn's warbler, or Dohrn's thrush-babbler, a species ''Sylvia dohrni'' in the famil ...

. It is a member of genus ''

Catharus The genus ''Catharus'' is an evolutionary clade of forest-dwelling passerine birds in the family Thrush (bird), Turdidae (thrushes), commonly known as nightingale-thrushes. The extant species are widely distributed across the Americas and are des ...

'' 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 William Swainson Fellow of the Linnean Society, FLS, Fellow of the Royal Society, FRS (8 October 1789 – 6 December 1855), was an English ornithologist, Malacology, malacologist, Conchology, conchologist, entomologist and artist. Life Swains ...

, an

English English usually refers to: * English language * English people English may also refer to: Culture, language and peoples * ''English'', an adjective for something of, from, or related to England * ''English'', an Amish ter ...

ornithologist Ornithology, from Ancient Greek ὄρνις (''órnis''), meaning "bird", and -logy from λόγος (''lógos''), meaning "study", is a branch of zoology dedicated to the study of birds. Several aspects of ornithology differ from related discip ...

Etymology

The genus name ''Catharus'' comes from the

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

, "pure or clean" and refers to the plumage of the

orange-billed nightingale-thrush The orange-billed nightingale-thrush (''Catharus aurantiirostris'') is a species of bird in the family Turdidae. It is found in Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Trinidad and Tobago, and Venezuela. ...

''C. aurantiirostris''. The specific ''ustulatus'' is

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

for "burnt", from , "to burn".

Habitat

The breeding

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

of Swainson's thrush is

conifer Conifers () are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a sin ...

ous woods with dense undergrowth across

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

, and the northern United States; also,

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 ...

wooded areas on the

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the cont ...

coast of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

Range and distribution

These birds

migrate Migration, migratory, or migrate may refer to: Human migration * Human migration, physical movement by humans from one region to another ** International migration, when peoples cross state boundaries and stay in the host state for some minimum le ...

to southern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

and as far south as

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

. The coastal

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 ...

migrate down the Pacific coast of North America and winter from

Costa Rica Costa Rica, officially the Republic of Costa Rica, is a country in Central America. It borders Nicaragua to the north, the Caribbean Sea to the northeast, Panama to the southeast, and the Pacific Ocean to the southwest, as well as Maritime bo ...

, whereas the continental birds migrate eastwards within North America (a substantial detour) and then travel southwards via

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

to winter from

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

Bolivia Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...

. Swainson's thrush is a very rare vagrant to western

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

. It has also occurred as a vagrant in northeast Asia.

Threats

This species may be displaced by the

hermit thrush The hermit thrush (''Catharus guttatus'') is a medium-sized North American thrush. Taxonomy It is not very closely related to the other North American migrant species of ''Catharus'', but rather to the Mexican russet nightingale-thrush. T ...

where their ranges overlap. Possibly, the latter species adapts more readily to human encroachment upon its habitat. At least in the winter quarters, Swainson's thrush tends to keep away from areas of human construction and other activity.

Description

This species is in length. The wingspan averages at and the wing chord is . The bill measures in length and the tarsus is long. This species' body mass can range from . This thrush has the white-dark-white underwing pattern characteristic of ''Catharus'' thrushes. Adults are brown on the upperparts. The underparts are white with brown on the flanks; the breast is lighter brown with darker spots. They have pink legs and a light brown eye ring. Birds in the east are more olive-brown on the upperparts; western birds are more reddish brown. This bird's song is a hurried series of flute-like tones spiralling upwards.

Diet

They forage on the forest floor, also in trees. Swainson's thrushes mainly eat insects, fruits and berries. They make a cup nest on a horizontal tree branch. Its song is said by local tribes to make

salmonberries ''Rubus spectabilis'', the salmonberry, is a species of bramble in the rose family Rosaceae, native to the west coast of North America from west-central Alaska to California, inland as far as Idaho. Like many other species in the genus ''Rubus' ...

ripen, including the

Saanich people The Saanich people ( ) are a Central Coast Salish people indigenous to parts of British Columbia and western Washington state. The W̱SÁNEĆ peoples are represented by the Tsartlip, Pauquachin, Tsawout, Tseycum and Malahat First Nat ...

who claim the bird says, "''xwexwelexwelexwelexwesh!''" meaning "ripen, ripen, ripen, ripen!" A similar belief appears among the

Tlingit The Tlingit or Lingít ( ) are Indigenous peoples of the Pacific Northwest Coast of North America. , they constitute two of the 231 federally recognized List of Alaska Native tribal entities, Tribes of Alaska. Most Tlingit are Alaska Natives; ...

Haida Haida may refer to: Haida people Many uses of the word derive from the name of an indigenous people of the Pacific Northwest Coast of North America. * Haida people, an Indigenous ethnic group of North America (Canada) ** Council of the Haida Nati ...

Haisla Haisla may refer to: * Haisla people, an indigenous people living in Kitamaat, British Columbia, Canada. * Haisla language, their northern Wakashan language. * Haisla Nation The Haisla Nation is the Indian Act-mandated band government which repr ...

, Oweekeno, Kwakwaka'wakw, Nuu-Chah-Nulth,

Ditidaht The Ditidaht ee-tee-dotFirst Nation is a First Nations in Canada, First Nations band government on southern Vancouver Island in British Columbia, Canada. The government has 17 reserve lands: Ahuk, Tsuquanah, Wyah, Clo-oose, Cheewat, Sarque, ...

, Sḵwx̱wú7mesh, and the

Straits Salish Northern Straits Salish (also referred to as North Straits Salish) is a language composed of several mutually-intelligible dialects within the Coast Salish language family spoken in western Washington and British Columbia. The various dialects ...

people.

Subspecies

Four subspecies are recognised, ''Cathartus ustulatus alame'', ''C. u. swainsoni'', ''C. u. ustulatus'' and ''C. u. oedicus''. Subspecies ''Cathartus ustulatus alame'' and ''C. u. swainsoni'' summer east of the

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

Coast Mountains The Coast Mountains () are a major mountain range in the Pacific Coast Ranges of western North America, extending from southwestern Yukon through the Alaska Panhandle and virtually all of the British Columbia Coast, Coast of British Columbia sout ...

, the Cascades and the

Sierra Nevada The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...

, and ''C. u. ustulatus'' and ''C. u. oedicus'' summer west of these ranges. There is a small area of overlap in the Coast Mountains. Recent

molecular systematics 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 ...

work confirms that these two pairs of subspecies form two genetically distinct

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

s, referred to as the continental and coastal clades, which diverged during the Late

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

era, probably about 10,000 years ago as the last ice age came to its end and habitats shifted across North America. The genetic differences between the subspecies, and the circuitous migratory route of the continental birds, strongly suggest that these species underwent a rapid range expansion following the end of the last

ice age An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages, and g ...

, with populations originally summering in the south-east of North America expanding their ranges northwards and westwards as the ice retreated. Details of the molecular genetic analysis support the hypothesis of rapid expansion of both coastal and continental populations. The current migratory routes of the continental birds, especially the western populations, are not optimal in ecological terms, and presumably represent an inherited, historical route pattern that has not yet adapted to the birds' modern population locations. These results notwithstanding, analysis of

mtDNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in ...

cytochrome ''b'' and

NADH dehydrogenase NADH dehydrogenase is an enzyme that converts nicotinamide adenine dinucleotide (NAD) from its reduced form (NADH) to its oxidized form (NAD+). Members of the NADH dehydrogenase family and analogues are commonly systematically named using the f ...

subunit 2 as well as

nuclear Nuclear may refer to: Physics Relating to the nucleus of the atom: *Nuclear engineering *Nuclear physics *Nuclear power *Nuclear reactor *Nuclear weapon *Nuclear medicine *Radiation therapy *Nuclear warfare Mathematics * Nuclear space *Nuclear ...

β-fibrinogen Fibrinogen beta chain, also known as FGB, is a gene found in humans and most other vertebrates with a similar system of blood coagulation. The protein encoded by this gene is the beta component of fibrinogen, a blood-borne glycoprotein composed ...

intron An intron is any nucleotide sequence within a gene that is not expressed or operative in the final RNA product. The word ''intron'' is derived from the term ''intragenic region'', i.e., a region inside a gene."The notion of the cistron .e., gen ...

sequence In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members (also called ''elements'', or ''terms''). The number of elements (possibly infinite) is cal ...

dataWinker & Pruett (2006) shows that Swainson's thrush is the most ancient North American species of its genus; it is not closely related to other ''Catharus'' and the outward similarities with the other North American species are due to

convergent evolution Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last comm ...

Gallery

File:Swainson’s Thrush.jpg, Swainson's thrush on South Padre Island, Texas File: Swainson’s_Thrush_Tex.jpg , On South Padre Island, Texas File:Catharus ustulatus Charlie Lake.jpg, A Swainson's thrush in British Columbia

Footnotes

References

* Foster, Mercedes S. (2007):
The potential of fruiting trees to enhance converted habitats for migrating birds in southern Mexico.
''Bird Conservation International'' 17(1): 45–61. * Ruegg, K. C., & Smith, T.B. (2002).
Not as the crow flies: a historical explanation for circuitous migration in Swainson's thrush (''Catharus ustulatus'').
'' Proc. R. Soc. B'' 269(1498) 1375–1381. * Winker, Kevin & Pruett, Christin L. (2006):
Seasonal migration, speciation, and morphological convergence in the avian genus ''Catharus'' (Turdidae).
''

Auk Auks or alcids are birds of the family Alcidae in the order Charadriiformes. The alcid family includes the Uria, murres, guillemots, Aethia, auklets, puffins, and Brachyramphus, murrelets. The family contains 25 extant or recently extinct speci ...

'' 123(4): 1052–1068. rticle in English with Spanish abstract DOI: 10.1642/0004-8038(2006)123 052:SMSAMC.0.CO;2 PDF fulltext]

External links

Swainson's Thrush Species Account
– Cornell Lab of Ornithology

– USGS Patuxent Bird Identification InfoCenter

– naturesongs.com * * * {{Taxonbar, from=Q545006 Catharus, Swainson's thrush Native birds of Alaska Birds of Canada Native birds of the Northwestern United States Wintering birds of South America

Swainson's thrush Swainson's thrush (''Catharus ustulatus''), also called olive-backed thrush, russet-backed thrush, and salmonberry bird is a medium-sized thrush. It is a member of genus ''Catharus'' and is typical of it in terms of its subdued coloration and bea ...

Taxa named by Thomas Nuttall