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English Names: Brewer's sparrow Scientific Name: Spizella breweri Spanish Names: gorrión de Brewer |
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View all images of Spizella breweri |
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Brewer's Sparrow (Spizella breweri)
Distinguishing FeaturesVery plain, small, and relatively long-tailed; sandy-brown above with narrow black streaks on back and crown, brown ear patch, plain pale gray below. HabitatOpen desert, especially creosote flats (winter). Feeding• Diet: Sparrows in the Sonoran Desert region feed mostly on insects and seeds. • Behavior: Brewer's Sparrow forages on the ground or in low vegetation usually in flocks. Life HistoryBecause of their generally brownish and often nondescript coloring, identifying sparrows can be a difficult and often unrewarding exercise for the beginning birder. But with a little persistence the birder can learn to recognize these species by their intricate markings and often engaging songs. The sparrows of the Sonoran Desert live near the ground or very close to it. The majority nest as isolated pairs and aggressively defend their nesting areas by driving away intruders of their own species. The females of most of the Sonoran Desert species are responsible for nest building. Cup-shaped nests made of twigs and weeds are located in dense low-growing brush or cacti, or on the ground. A range of from two to five eggs, which may be plain or spotted, are most often incubated by the female only; usually both parents share in feeding the young. Sparrows
Most people, at the mention of sparrows, think first of the House Sparrow. That bird is familiar enough — it thrives in urbanized areas, including southwestern cities — but it belongs to a family that is native to the Old World. The sparrows that occur naturally on this continent are a much more diverse group, many with distinctive patterns and musical songs. All of them have short thick bills — designed for cracking open seeds, a major part of their winter diets— but all eat many insects as well, especially in warm weather. The ultimate dryland sparrow is the Black-throated Sparrow, a smartly patterned bird that thrives year-round in the Sonoran Desert and also in the much sparser plant growth of the Chihuahuan Desert farther east. However, several other species are permanent residents around the edges of this habitat. Song Sparrows (of a distinctive local form, paler and redder than Song Sparrows elsewhere) are common along desert rivers where there is still healthy riparian growth. Rufous-winged Sparrows survive in desert patches that have escaped the effects of overgrazing, while Rufous-crowned Sparrows haunt rocky canyons and foothills. The towhees, big sparrows that forage by scratching actively on the ground, are represented by Abert's Towhees along lowland rivers and Canyon Towhees on drier slopes. Winter is the season when sparrow diversity peaks, as more species move in from the north. Flocks of White-crowned Sparrows range along the brushy arroyos, flocks of Brewer's Sparrows are common on the more open flats, and several other species appear as well. Because they feed largely on seeds at this season, their numbers vary: if the summer and fall rains have produced a good crop of annual weed and grass seeds, the winter desert may be alive with sparrows. |
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