The Savannah sparrow (''Passerculus sandwichensis'') is a small
New World sparrow. It was the only member of the genus ''
Passerculus'' and is typically the only widely accepted member. Comparison of
mtDNA NADH dehydrogenase subunit
Subunit may refer to:
*Subunit HIV vaccine, a class of HIV vaccine
*Protein subunit, a protein molecule that assembles with other protein molecules
*Monomer, a molecule that may bind chemically to other molecules to form a polymer
*Sub-subunit, a ...
2 and 3
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 calle ...
s indicates that the Ipswich sparrow, formerly usually considered a valid species (as ''Passerculus princeps''), is a well-marked
subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
of the Savannah sparrow, whereas the southwestern large-billed sparrow should be recognized as a distinct species (''Passerculus rostratus'').
[
The species name ''sandwichensis'' is Latin, of place, Sandwich, Unalaska, or Aleutians area, from which came the first subspecies, Aleutian Savannah sparrow, to be described. The common name honors Savannah, Georgia where Alexander Wilson discovered the species in 1811.
]
Distribution
This 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 are distinguished from other orders of birds by t ...
bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
breeds in Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...
, Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
, northern, central and Pacific coastal United States, Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
and Guatemala
Guatemala ( ; ), officially the Republic of Guatemala ( es, República de Guatemala, links=no), is a country in Central America. It is bordered to the north and west by Mexico; to the northeast by Belize and the Caribbean; to the east by H ...
. The Pacific and Mexican breeders are resident, but other populations are migratory, wintering from the southern United States across Central America
Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...
and the Caribbean
The Caribbean (, ) ( es, El Caribe; french: la Caraïbe; ht, Karayib; nl, De Caraïben) is a region of the Americas that consists of the Caribbean Sea, its islands (some surrounded by the Caribbean Sea and some bordering both the Caribbean Se ...
to northern South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
. It is a very rare vagrant to western Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
.[
]
Description
This species has a typically sparrow
Sparrow may refer to:
Birds
* Old World sparrows, family Passeridae
* New World sparrows, family Passerellidae
* two species in the Passerine family Estrildidae:
** Java sparrow
** Timor sparrow
* Hedge sparrow, also known as the dunnock or hedg ...
-like dark-streaked brown back, and whitish underparts with brown or blackish breast and flank streaking. It has whitish crown and 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 ...
stripes, sometimes with some yellow (more often near 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 eating, preening, manipulating objects, killing prey, fighting, probing for food ...
). The cheeks are brown and the throat white. The flight feather
Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tail ...
s are blackish-brown with light brown or white border. The eyes are dark. The feet and legs are horn-colored, as is the lower part of the bill, with the upper part being dark grey.
The Savannah sparrow is a very variable species, with numerous subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
, several of which have been split as separate species at various times. The different forms vary principally in the darkness of the plumage. The variation generally follows Gloger's rule, with Alaskan and interior races the palest, and southwestern coastal forms the darkest. There are some exceptions, though, most conspicuously in some island populations that presumably were strongly affected by founder effect
In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. It was first fully outlined by Ernst Mayr in 1942, using ...
s. The general pattern of variation has a fairly clear divide, southwest of which the birds become notably darker; this agrees quite well with the limit between ''P. sandwichensis'' and ''P. (s.) rostratus''. Savannah sparrows show some variation in size across subspecies. The total length can range from , wingspan ranges from and body mass from . In the nominate subspecies, the body weight averages .[''CRC Handbook of Avian Body Masses'' by John B. Dunning Jr. (Editor). CRC Press (1992), .]
The Savannah sparrows proper (see below
Below may refer to:
*Earth
*Ground (disambiguation)
*Soil
*Floor
*Bottom (disambiguation)
Bottom may refer to:
Anatomy and sex
* Bottom (BDSM), the partner in a BDSM who takes the passive, receiving, or obedient role, to that of the top or ...
) are very similar, and migrant birds can not usually be related to a breeding population with certainty. The resident or partially migratory subspecies are well distinguishable by size and, particularly between groups, coloration.
Behavior
These birds forage on the ground or in low bushes; particularly in winter they are also found in grazed
In agriculture, grazing is a method of animal husbandry whereby domestic livestock are allowed outdoors to roam around and consume wild vegetations in order to convert the otherwise indigestible (by human gut) cellulose within grass and other f ...
low-growth grassland. They mainly eat seeds, but also eat insects in the breeding season. They are typically encountered as pairs or family groups in the breeding season, and assemble in flocks for the winter migration. The flight call is a thin ''seep''. '' Sensu lato'', the Savannah sparrow is considered a threatened species
Threatened species are any species (including animals, plants and fungi) which are vulnerable to endangerment in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of ''critical depensa ...
by the IUCN
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
.[ The song is mixture of ''chirps'' and trills.
]
Systematics
Seventeen subspecies (including the large-billed sparrows) are currently recognized, though many are only described from wintering birds and much of the variation seems to be clinal. Four additional subspecies are no longer generally accepted. The complex is usually divided into several groups:
Savannah sparrows proper
All are migratory; wintering ranges overlap widely.
* ''P. s. labradorius'', breeds in Newfoundland
Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region ...
, Labrador
, nickname = "The Big Land"
, etymology =
, subdivision_type = Country
, subdivision_name = Canada
, subdivision_type1 = Province
, subdivision_name1 ...
, and N Quebec
Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...
* ''P. s. oblitus'', breeds in north Ontario
Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...
and Manitoba
Manitoba ( ) is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population o ...
* ''P. s. savanna'' (eastern Savannah sparrow), breeds in the northeast US and adjacent Canada (includes ''P. s. mediogriseus'')
* ''P. s. sandwichensis'' (Aleutian Savannah sparrow), breeds on the Aleutian Islands
The Aleutian Islands (; ; ale, Unangam Tanangin,”Land of the Aleuts", possibly from Chukchi language, Chukchi ''aliat'', "island"), also called the Aleut Islands or Aleutic Islands and known before 1867 as the Catherine Archipelago, are a cha ...
and west Alaskan Peninsula
The Alaska Peninsula (also called Aleut Peninsula or Aleutian Peninsula, ale, Alasxix̂; Sugpiaq: ''Aluuwiq'', ''Al'uwiq'') is a peninsula extending about to the southwest from the mainland of Alaska and ending in the Aleutian Islands. The p ...
* ''P. s. anthinus'', breeds in the remainder of Alaska, south and east to central British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...
and north of the Great Plains
The Great Plains (french: Grandes Plaines), sometimes simply "the Plains", is a broad expanse of flatland in North America. It is located west of the Mississippi River and east of the Rocky Mountains, much of it covered in prairie, steppe, an ...
to Manitoba
* ''P. s. brooksi'' (dwarf Savannah sparrow), breeds in southernmost British Columbia to northernmost California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...
* ''P. s. alaudinus'', breeds in coastal northern and central California
* ''P. s. nevadensis'', breeds in the northern Great Plains and the Great Basin
The Great Basin is the largest area of contiguous endorheic basin, endorheic watersheds, those with no outlets, in North America. It spans nearly all of Nevada, much of Utah, and portions of California, Idaho, Oregon, Wyoming, and Baja California ...
* ''P. s. brunnescens'', breeds from central Mexico south to Guatemala (includes ''P. s. rufofuscus'')
''P. s. wetmorei'' is a doubtful subspecies that may breed in the mountains of Guatemala. It is known from only five specimens, collected June 11–17, 1897, in Huehuetenango Department.
Ipswich sparrow
Some post-breeding dispersal. Formerly considered a distinct species.[
* ''P. s. princeps'', breeds almost exclusively on Sable Island
:The Ipswich sparrow is somewhat larger and paler in color than other eastern Savannah sparrows. The breast streaks are narrower and pale brown. Some birds overwinter on the island; others migrate south along the Atlantic coast, usually departing later and returning sooner than mainland birds. Some birds interbreed with ''P. s. savanna'' in ]Nova Scotia
Nova Scotia ( ; ; ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. Nova Scotia is Latin for "New Scotland".
Most of the population are native Eng ...
. These birds frequently raise three broods in a year. This bird was first observed in winter on the dunes near the town of Ipswich, Massachusetts
Ipswich is a coastal town in Essex County, Massachusetts, United States. The population was 13,785 at the 2020 census. Home to Willowdale State Forest and Sandy Point State Reservation, Ipswich includes the southern part of Plum Island. A reside ...
.
Large-billed sparrows
The large-billed sparrows proper are two dark, large and strong-billed subspecies:
* ''Passerculus rostratus/sandwichensis rostratus'', which breed on the Gulf Coast of northeast Baja California
Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...
and northwest Sonora
Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. The state is d ...
(some post-breeding dispersal).
* ''P. r./s. atratus'', resident on the coast of central Sonora
Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. The state is d ...
to central Sinaloa
Sinaloa (), officially the Estado Libre y Soberano de Sinaloa ( en, Free and Sovereign State of Sinaloa), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. It is d ...
(resident)
The Belding's (Savannah/large-billed) sparrows are all-year residents of salt marsh
A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is dominated ...
es of the California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...
n Pacific coast. They are dark, rufous, and have rather long but not very hefty bills.
* ''P. r./s. beldingi'', resident on the Pacific coast from Morro Bay, California, to El Rosario, Baja California (includes ''P. r./s. bryanti'')
* ''P. r./s. anulus'', resident around Sebastián Vizcaíno Bay, Baja California
* ''P. r./s. guttatus'', resident around San Ignacio Lagoon
San Ignacio Lagoon (Laguna San Ignacio) is a lagoon located in Mulegé Municipality of the Mexican state of Baja California Sur, 59 kilometers (37 mi) from San Ignacio, Mexico, and Highway 1. It is one of the winter sanctuaries of the eastern ...
* ''P. r./s. magdalenae'', resident around Magdalena Bay
Magdalena Bay ( es, Bahía Magdalena) is a long bay in Comondú Municipality along the western coast of the Mexican state of Baja California Sur. It is protected from the Pacific Ocean by the unpopulated sandy barrier islands of Isla Magdalen ...
The San Benito (Savannah/large-billed) sparrow is a resident bird of the Islas San Benito off Baja California; a stray bird was observed on Cedros Island on April 21, 1906.[
* ''P. r./s. sanctorum''
:This is a large-bodied and large-billed subspecies, similar to ''rostratus''. They utilize different habitat and their breeding season does not seem to coincide][For late April 1906, Thayer & Bangs (1907) report nestlings, young birds molting into adult plumage, but no eggs anymore. Rising ''in'' Zink ''et al.'' (2005) found no breeding activity in late April 1999. Consequently, breeding seems to take place in the winter months, with the last young fledging in April/May.] with that of Belding's sparrows. However, their bill size is 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 com ...
and their habitat choice simply to the lack of alternatives on their barren island home; altogether, it appears to be a fairly recent offshoot from the Belding's sparrows group. It appears as distinct evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
arily from these as does the Ipswich sparrow from the Savannah sparrow proper group, only that there seems to have been more gene flow
In population genetics, gene flow (also known as gene migration or geneflow and allele flow) is the transfer of genetic material from one population to another. If the rate of gene flow is high enough, then two populations will have equivalent a ...
and/or a larger founder population
In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. It was first fully outlined by Ernst Mayr in 1942, using ...
in the case of the latter.
Gallery
File:Savannah Sparrow.jpg, Probably ''P. s. sandwichensis'', Alaska
File:Passerculus sandwichensis.JPG, Probably ''P. s. anthinus'', Alaska
File:Savannah Sparrow chicks in nest.jpg, ''P. s. labradorius'' nest
File:Savannah Sparrow, Newfoundland.jpg, ''P. s. labradorius'', Newfoundland
File:Passerculus sandwichensis.jpg, Probably a Belding's sparrow, wintering in California
Notes
References
Further reading
*
External links
Government of Canada Species at Risk Public Registry – Savannah sparrow
Savannah sparrow species account
– Cornell Lab of Ornithology
– USGS Patuxent Bird Identification InfoCenter
*
*
*
{{Taxonbar, from=Q287893
savannah sparrow
The Savannah sparrow (''Passerculus sandwichensis'') is a small New World sparrow. It was the only member of the genus '' Passerculus'' and is typically the only widely accepted member. Comparison of mtDNA NADH dehydrogenase subunit 2 and 3 sequ ...
American sparrows
Birds of North America
savannah sparrow
The Savannah sparrow (''Passerculus sandwichensis'') is a small New World sparrow. It was the only member of the genus '' Passerculus'' and is typically the only widely accepted member. Comparison of mtDNA NADH dehydrogenase subunit 2 and 3 sequ ...
savannah sparrow
The Savannah sparrow (''Passerculus sandwichensis'') is a small New World sparrow. It was the only member of the genus '' Passerculus'' and is typically the only widely accepted member. Comparison of mtDNA NADH dehydrogenase subunit 2 and 3 sequ ...