White-throated sparrow

White-throated sparrow
White-throated sparrow in Cap Tourmente National Wildlife Area, Quebec, Canada
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Suborder: Passeri
Superfamily: Passeroidea
Family: Emberizidae
Genus: Zonotrichia
Species: Z. albicollis
Binomial name
Zonotrichia albicollis
(Gmelin, 1789)
Range of Z. albicollis      Breeding range     Year-round range     Wintering range

The white-throated sparrow (Zonotrichia albicollis) is a passerine bird of the American sparrow family Emberizidae.

Etymology

The genus name Zonotrichia is from Ancient Greek zone, "band", and thrix, trikhos, "hair". The specific albicollis is from Latin albus, white, and collum, "neck".[2]

Description

Birds of the white-striped form have tan only at the lores

The white-throated sparrow is a passerine bird of the American sparrow family Emberizidae. It measures 15 to 19 cm (5.9 to 7.5 in) in length with a wingspan of 23 cm (9.1 in). Typical weight is 22 to 32 g (0.78 to 1.13 oz), with an average of 26 g (0.92 oz).[3][4] Among standard measurements, the wing chord is 6.3 to 7.9 cm (2.5 to 3.1 in), the tail is 6.8 to 7.7 cm (2.7 to 3.0 in), the bill is 1 to 1.2 cm (0.39 to 0.47 in) and the tarsus is 2.2 to 2.4 cm (0.87 to 0.94 in).[5] They are similar in appearance to the white-crowned sparrow, but with white throat markings and yellow lores.

Ottawa, Ontario

There are two adult plumage variations known as the tan-striped and white-striped forms. On the white-striped form the crown is black with a white central stripe. The supercilium is white as well. The auriculars are gray with the upper edge forming a black eye line.[3]

On the tan form, the crown is dark brown with a tan central stripe. The supercilium is tan as well. The auriculars are gray/light brown with the upper edge forming a brown eye line. Both variations feature dark eyes, a white throat, yellow lores and gray bill.[3] There is variation and some individuals may show dark lateral stripes of each side of the throat.

They almost always pair with the opposite color morph for breeding. The two color morphs occur in approximately equal numbers. Both male and female white-striped birds are more aggressive than tan-striped birds during the breeding season.[6][7]

The breast has gray/tan streaks and the streaks continue down the flanks but the belly is generally light gray. The wings are rufous with two distinct white wing bars. Sexes are morphologically similar.[3]

Behavior

Reproduction

White-throated sparrows breed in central Canada and New England. They nest either on the ground under shrubs or low in trees in deciduous or mixed forest areas and lay three to five brown-marked blue or green-white eggs.

Wintering and migration

In winter, this species migrates to the southern and eastern United States. It stays year round in the Atlantic provinces of Canada. This bird is a rare vagrant to western Europe. Alongside some other species such as the cardinal, dark-eyed junco, song sparrow and chickadees, this species ranks among the most abundant native birds during winter in eastern North America.[8]

Despite a high level of con-specific rivalry within white-throated sparrows, this species is often dominated by other seed-eating winter residents, even those that are no larger than itself like the song sparrow, and thus may endure high levels of predation while foraging since restricted to sub-optimal sites at times by competition.[9] Not to mention numerous mammalian carnivores, at least ten avian predators often hunt them and they are among the most regular prey species for some smaller raptors, i.e. the sharp-shinned hawk and eastern screech-owl.[10][11]

Diet

These birds forage on the ground under or near thickets or in low vegetation. They mainly eat seeds, insects and berries, and are attracted to bird feeders.

Song and calls

There are at least two distinct songs sung by this species. One consists of an initial note, followed by three or so repeated notes at an interval of about a major third above. The second song consists of an initial note, a second a whole step lower, and a third note, repeated two or three times, about a minor third below that. This second song is commonly described by use of mnemonics with the cadence of "Po-or Sam Peabody, Peabody, Peabody" (or "O-oh sweet Canada, Canada, Canada") The rhythm is very regular, and the timbre could be described as pinched. These musical intervals are only approximate; to a human ear the song often sounds out of tune. The repeated note will often change in pitch very slightly, contributing to this effect.

The white-throated sparrow also has at least two calls, in addition to its song.

Footnotes

  1. ↑ BirdLife International (2012). "Zonotrichia albicollis". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
  2. ↑ Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London, United Kingdom: Christopher Helm. pp. 38, 414. ISBN 978-1-4081-2501-4.
  3. 1 2 3 4 Sibley, David A. (2000). National Audubon Society The Sibley Field Guide to Birds. New York: Alfred A. Knopf. p. 494. ISBN 0-679-45122-6.
  4. ↑ Wolfson, Albert (1954). "Body Weight and Fat Deposition in Captive White-Throated Sparrows in Relation to the Mechanics of Migration". The Wilson Bulletin. 66 (2): 112–118. JSTOR 4158288.
  5. ↑ Byers, Clive; Olsson, Urban (1995). Sparrows and Buntings: A Guide to the Sparrows and Buntings of North America and the World. Houghton Mifflin. ISBN 978-0395738733.
  6. ↑ GrrlScientist (26 May 2011). "Sparrows show us a new way to have sexes". The Guardian. Retrieved 2015-06-29.
  7. ↑ Arnold, Carrie (24 November 2016). "The sparrow with four sexes". Nature. 539: 482–484. doi:10.1038/539482a. Retrieved 2016-12-03.
  8. ↑ Bock, C. E.; Prickles, R. E. (1983). "Range size and local abundance of some North American songbirds: a positive correlation". The American Naturalist. 122 (2): 295–299. JSTOR 2461236.
  9. ↑ Piper, W. H. (1990). "Exposure to predators and access to food in wintering white-throated sparrows Zonotrichia albicollis". Behaviour. 112 (3/4): 284–298. JSTOR 4534842.
  10. ↑ Roth, T. C., II; Lima, S. L. (2007). "The predatory behavior of wintering Accipiter hawks: temporal patterns in activity of predators and prey". Oecologia. 152 (1): 169–178. doi:10.1007/s00442-006-0638-2.
  11. ↑ VanCamp, L. F.; Henry, C. J. (1975). "The screech owl: its life history and population ecology in northern Ohio". North American Fauna (75): 1–65. doi:10.3996/nafa.71.0001.
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