Cassins Sparrow (Aimophila cassinii)

Cassins Sparrow

[order] PASSERIFORMES | [family] Emberizidae | [latin] Aimophila cassinii | [UK] Cassins Sparrow | [FR] Bruant de Cassin | [DE] Cassinammer | [ES] Zacatonero de Cassin | [NL] Cassins’ Gors

Subspecies

Monotypic species

Physical charateristics

A drab sparrow of open arid country; underparts dingy without markings, or with faint streaking on flanks. Pale or whitish tips
on gray-brown outer tail feathers. Best clue is the “skylarking” song. Botteri’s Sparrow (very local) does not skylark.

Listen to the sound of Cassins Sparrow

[audio:http://www.aviflevoland.nl/sounddb/C/Cassins Sparrow.mp3]

Copyright remark: Most sounds derived from xeno-canto

wingspan min.: 20 cm wingspan max.: 21 cm
size min.: 13 cm size max.: 15 cm
incubation min.: 12 days incubation max.: 14 days
fledging min.: 9 days fledging max.: 10 days
broods: 1   eggs min.: 3  
      eggs max.: 5  

Range

North America, Middle America : Southcentral, Southwest USA, North Mexico

Habitat

Desert grassland, brushy fields.
Breeds in a variety of situations having good ground cover of grass and low shrubs; ranges from open grassland with only scattered shrubs to brushy areas with grassy understory. During migration and in winter, also found in pure grassland, brushy areas,
deserts.

Reproduction

Somewhat irregular in its nesting, especially in western and northern parts of range; may appear in numbers and breed only in years with good rainfall. Male advertises territory with flight song displ
ay, flying up to about 20′ and then gliding and fluttering down, while singing. In courtship, male may chase female, or may display with wings and tail partly spread and fluttering.
Nest:
Site is usually on the ground, well hidden among weeds or at the base of a bush. Sometimes up to a foot above ground in a low shrub. Nest is an open cup made of dry grass, weed stems, bark, plant fibers, lined with fine grass.
Eggs: 3-5, usually 4. White, unmarked. Details of incubation are not well known.
Young: Both parents feed the nestlings. Age at which young leave the nest is not well known.

Feeding habits

Mainly insects and seeds. Summer diet is partly to mostly insects, especially grasshoppers, caterpillars, moth
s, and beetles, also many others. Young are fed almost entirely on insects. Also eats seeds, especially in fall and winter, mainly those of weeds and grasses.
Behavior: Forages mostly or entirely on the ground, hopping about in relatively open areas, taking items from the ground or from plant stems.

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Cassins Sparrow status Least Concern

Migration

Southwestern United States, northeastern Mexico. Expands range to dash line in some years due to environmental change.

Distribution map

Cassins Sparrow distribution range map

Leave a Reply

Your email address will not be published. Required fields are marked *