Rufous-crowned Sparrow, Aimophila ruficeps

Rufous-crowned Sparrow, Aimophila ruficeps scottii. Photograph taken within a residential community in Hereford, Arizona, June 2011. Photograph and identification courtesy of Bob Behrstock, Sierra Vista, Arizona (naturewideimages.com).

Rufous-crowned Sparrow, Aimophila ruficeps simulans. Photograph taken within Reserva Monte Mojino, Alamos, Sonora, May 2018. Photograph and identification courtesy of David F Smith, Alamos, Sonora.

The Rufous-crowned Sparrow, Aimophila ruficeps scottii and Aimophilia ruficeps simulans, are two of twelve subspecies of Rufous-crowned Sparrow, ten of which are found in Mexico. They are a member of the Passerellidae Family of New World Sparrows, which has one hundred thirty-two members placed in thirty genera, and is one of three global species of the Aimophila Genus. They are known in Mexico as chingolo coronirrufo.

The Rufous-crowned Sparrow is sparrow-shaped and medium sized in stature. They are sexually dimorphic with the males being larger than the females; however, the sexes have similar plumages. They have a chestnut, rufous, or rusty crown, grayish-brown underparts and are often streaked with rusty gray and unmarked grayish to white underparts. Their ear covert are dark and they have a distinct black malar stripe, a prominent eye-ring.

The Rufous-crowned Sparrow is found in steep, dry, rocky slopes vegetated with a low cover of scattered shrubs which are interspersed with patches of grasses, forbs, and bare ground within dry hillsides and canyons at elevations up to 2,195 m (7,200 feet). They are sedentary permanent residents being non-migratory. They are ground forages consuming seeds and insects with heavy vegetation. They primarily consume grass, young plant shoots, forb seeds and insects. They are known for their scolding, nasal call and calls of the male often singing from prominent perches. They have life spans of up to four years. The Rufous-crowned Sparrow is shy and secretive residing in inaccessible habitat making it very difficult to study and very little has been documented about their biology and behavioral patterns.

The Rufous-crowned Sparrow is similar to and can be confused with the American Tree Sparrow, Spizella arborea, the Chipping Sparrow, Spizella passerine, the Oaxaca Sparrow, Aimophila notosticta, the Rufous-winged Sparrow, Aimophila carpalis, the Rusty Sparrow, Aimophila rufescens, the Rufous-winged Sparrow, Aimophila carpalis, and immature White-crowned Sparrows, Zonotrichia leucophrys, all of which may occur seasonally in some areas with Rufous-crowned Sparrows.

In Mexico the Rufous-crowned Sparrow is widely distributed and found in northwest Baja California and in the interior regions from eastern Sonora and western Chihuahua and from north central Coahuila south to central Oaxaca, with an isolated population in southern Tamaulipas. The scottii subspecies is found in northeast Sonora and northwest Chihuahua. The simulans subspecies is found in southeast Sonora and southwest Chihuahua south to Nayarit and northern Jalisco.

From a conservation perspective the Rufous-crowned Sparrow is currently considered to be of Least Concern, with stable, widely-distributed populations. In some parts of their region they their populations are being threatened by the loss, degradation and fragmentation of their habitat as a result of urban and agricultural development.