Worthen's Sparrow
Encyclopedia
Worthen’s Sparrow is a species of American sparrow
that is endemic to northeastern Mexico
. It was first described by Ridgway in 1884 and named for American naturalist Charles K. Worthen. This small bird was listed as endangered
by the IUCN since 1994.
Juvenile's are characterized by brownish coloration of the head and chest, with dusky streaking on head and dark brown streaking on chest and flanks.
The song is a dry, chipping trill of 2–3 second duration, and is described as a cross between that of the Field Sparrow
and Chipping Sparrow
.
The species is similar in appearance to the Field Sparrow
(Spizella pusilla). However, they differ in plumage, habitat, and song.
The species nests from May–July, and usually lays 3–4 eggs. Single-species flocks form after the breeding season and are strongly attracted to permanent sources of water.
The species is not migratory
, however a few sightings of individuals have taken place throughout the north-west region of Mexico. Only one individual has ever been identified (shot) in North America, and it was by Rieber on June 16, 1884 near Silver City, New Mexico
. This individual, the first of the species to be described, is the type specimen.
, Coahuila
, Nuevo León
, and Tamaulipas
, however presently is only known to occur from south-eastern Coahuila
to western Nuevo León
.
Spizella wortheni prefers open, arid shrub-grassland at elevations of 1200–2450 m (3,937–8,038.1 ft). For foraging, the species prefers open areas with low grasses. For nesting and cover, it usually inhabits low, dense shrubs.
As of 2004, the current population was estimated to be between 100–120 individuals.
. By protecting this area, the appeal will conserve habitat for the Worthen's Sparrow, Long-billed Curlew
, Burrowing Owl
, Mountain Plover
, Sprague's Pipit
, and Ferruginous Hawk
.
Emberizidae
The Emberizidae are a large family of passerine birds. They are seed-eating birds with a distinctively shaped bill.In Europe, most species are called buntings. In North America, most of the species in this family are known as sparrows, but these birds are not closely related to the sparrows, the...
that is endemic to northeastern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. It was first described by Ridgway in 1884 and named for American naturalist Charles K. Worthen. This small bird was listed as endangered
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
by the IUCN since 1994.
Description
Spizella wortheni can range in length from 12.5–14 cm. It is identifiable by its distinctive head pattern. It has a grey head with a rufous crown, a brown postocular stripe and a pink bill. It has grey-brown upperparts, with dark brown streaks. It has a grey bottom, and dark brown wings and tail. Its wings are "edged paler, with broad whitish to pale buff wing-bar, buffy-rufous tertial and secondary edging, and greyish lesser coverts."Juvenile's are characterized by brownish coloration of the head and chest, with dusky streaking on head and dark brown streaking on chest and flanks.
The song is a dry, chipping trill of 2–3 second duration, and is described as a cross between that of the Field Sparrow
Field Sparrow
The Field Sparrow is a small sparrow.Adults have brown upperparts, a light brown breast, a white belly, wing bars and a forked tail. They have a grey face, a rusty crown, a white eye ring and a pink bill....
and Chipping Sparrow
Chipping Sparrow
The Chipping Sparrow is a species of American sparrow in the family Emberizidae. It is widespread, fairly tame, and common across most of its North American range.-Description:...
.
The species is similar in appearance to the Field Sparrow
Field Sparrow
The Field Sparrow is a small sparrow.Adults have brown upperparts, a light brown breast, a white belly, wing bars and a forked tail. They have a grey face, a rusty crown, a white eye ring and a pink bill....
(Spizella pusilla). However, they differ in plumage, habitat, and song.
The species nests from May–July, and usually lays 3–4 eggs. Single-species flocks form after the breeding season and are strongly attracted to permanent sources of water.
The species is not migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
, however a few sightings of individuals have taken place throughout the north-west region of Mexico. Only one individual has ever been identified (shot) in North America, and it was by Rieber on June 16, 1884 near Silver City, New Mexico
Silver City, New Mexico
Silver City is a town in Grant County, New Mexico, in the United States. As of the 2000 census, the town population was 10,545. It is the county seat of Grant County. The city is the home of Western New Mexico University.-History:...
. This individual, the first of the species to be described, is the type specimen.
Habitat and range
Worthen's Sparrow is endemic to North-Eastern Mexico and currently occupies a 25 km² range. Populations formerly occurred in ZacatecasZacatecas
Zacatecas officially Estado Libre y Soberano de Zacatecas is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 58 municipalities and its capital city is Zacatecas....
, Coahuila
Coahuila
Coahuila, formally Coahuila de Zaragoza , officially Estado Libre y Soberano de Coahuila de Zaragoza is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico...
, Nuevo León
Nuevo León
Nuevo León It is located in Northeastern Mexico. It is bordered by the states of Tamaulipas to the north and east, San Luis Potosí to the south, and Coahuila to the west. To the north, Nuevo León has a 15 kilometer stretch of the U.S.-Mexico border adjacent to the U.S...
, and Tamaulipas
Tamaulipas
Tamaulipas officially Estado Libre y Soberano de Tamaulipas is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 43 municipalities and its capital city is Ciudad Victoria. The capital city was named after Guadalupe Victoria, the...
, however presently is only known to occur from south-eastern Coahuila
Coahuila
Coahuila, formally Coahuila de Zaragoza , officially Estado Libre y Soberano de Coahuila de Zaragoza is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico...
to western Nuevo León
Nuevo León
Nuevo León It is located in Northeastern Mexico. It is bordered by the states of Tamaulipas to the north and east, San Luis Potosí to the south, and Coahuila to the west. To the north, Nuevo León has a 15 kilometer stretch of the U.S.-Mexico border adjacent to the U.S...
.
Spizella wortheni prefers open, arid shrub-grassland at elevations of 1200–2450 m (3,937–8,038.1 ft). For foraging, the species prefers open areas with low grasses. For nesting and cover, it usually inhabits low, dense shrubs.
As of 2004, the current population was estimated to be between 100–120 individuals.
Conservation
The major threat to this species is habitat destruction. The grassland Worthen's Sparrow is specific to has progressively been plowed for agricultural practices and grazing. Currently there is a conservation effort being coordinated by the Bird Conservation Alliance and other organizations to protect the Saltillo Savanna in Mexico. The program, known as the Mexican Grasslands Appeal, seeks to purchase over 1000 acres (4 km²) of prime grassland habitat to protect and save this last great North American grasslandGrassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
. By protecting this area, the appeal will conserve habitat for the Worthen's Sparrow, Long-billed Curlew
Long-billed Curlew
The Long-billed Curlew, Numenius americanus, is a large North American shorebird of the family Scolopacidae. This species was also called "sicklebird" and the "candlestick bird". The species is native to central and western North America...
, Burrowing Owl
Burrowing Owl
The Burrowing Owl is a tiny but long-legged owl found throughout open landscapes of North and South America. Burrowing Owls can be found in grasslands, rangelands, agricultural areas, deserts, or any other open dry area with low vegetation. They nest and roost in burrows, such as those excavated...
, Mountain Plover
Mountain Plover
The Mountain Plover is a medium-sized ground bird in the plover family . It is misnamed, as it lives on level land...
, Sprague's Pipit
Sprague's Pipit
Sprague's Pipit is a small passerine bird that breeds in the short and mixed-grass prairies of North America and overwinters in the southwestern United States and northern Mexico. Easiest to identify by the distinctive descending call that is delivered in the breeding season from a considerable...
, and Ferruginous Hawk
Ferruginous Hawk
The Ferruginous Hawk , Buteo regalis , is a large bird of prey. It is not a true hawk like sparrowhawks or goshawks, but rather belongs to the broad-winged buteo hawks, known as "buzzards" in Europe...
.
See also
- National Geographic" Field Guide to the Birds of North America ISBN 0-7922-6877-6
- Zink, Robert M. and Donna L. Dittman. "Population structure and gene flow in the Chipping Sparrow and a hypothesis for evolution in the genus Spizella." 1993. Wilson Bulletin, 105 (3): 399-413.