Thick-billed Fox Sparrow - Subspecies

Subspecies

The megarhyncha complex breeds in mountains from southern Oregon to southern California east to the Sierra Nevada and shows little geographic variation. It interbreeds with the Slate-colored complex along a narrow contact zone from southern Oregon to western Nevada (Rising & Beadle 1996) but as noted above, gene flow is quite limited. Sibley (2000) indicates that this group has the most diagnostic call note, "a high, flat squeak (sic) teep like California Towhee".

• megarhyncha :

Breeds from Onion Mountains and Robinson's Butte (SW Oregon) south through inland N California to Kearsarge Pass (Inyo County), as well as the western flank of the Sierra Nevada in Mono County. Winters in C and S California and adjacent Mexico.(Weckstein et al. 2002)

More large-billed, duller, and grayer than schistacea Slate-colored Fox Sparrows; intermediate between the very large long-tailed stephensi and the more schistacea-like monoensis of this group; intergrades with former.(Weckstein et al. 2002)

• stephensi :

Breeds in areas of the S Sierra Nevada such as Fresno and Tulare Counties, Mount Pinos and San Gabriel, San Bernardino, and San Jacinto Mountains, California, to the Sierra San Mártir, N Baja California. In winter, migrates to lower elevations but generally does not migrate long distances.(Weckstein et al. 2002)

The largest, most massive-billed and longest-tailed fox sparrow; also very grey in coloration (Swarth 1920). Intergrades with megarhyncha (Weckstein et al. 2002).

• monoensis :

Breeds on the eastern flank of the Sierra Nevada in Mono County, California, and in the Walker River Range in adjacent Mineral County, Nevada. Winters from inland central California coastwards and south into Mexico.(Weckstein et al. 2002)

Somewhat intermediate between megarhyncha and schistacea Slate-colored Fox Sparrows, with a paler, ashy grey back.(Weckstein et al. 2002)

• brevicauda :

Breeds in the Mendocino Range of California, from the Yolla Bolly Mountains south to Snow Mountain and Sanhedrin Mountains. Migrates coastwards and south in winter.(Weckstein et al. 2002)

Similar to stephensi, but recognizable by more rusty tinge to brownish areas and the conspicuously shorter tail (Weckstein et al. 2002).

• fulva :

Mountaineous regions from C Oregon east of Cascades Range (Steens Mountain, Sisters and Keeno Mountains) to Modoc and Lassen Counties, California. Winters in southwesternmost California and adjacent Mexico.

A browner version of monoensis; in winter range, distinguished from olivacea Slate-colored Fox Sparrows by decidedly ruddy brown and larger bill (Weckstein et al. 2002).

• mariposae :

Breeding in a limited area in California between the headwaters of the Little Shasta River (Siskiyou County) to Yosemite National Park and Kearsarge Pass. Winter range undocumented (Weckstein et al. 2002) due to lack of distinctiveness but probably same as megarhyncha and monoensis.

Probably nothing more than intergrades between megarhyncha and monoensis; nowadays usually synonymized with the former (Rising & Beadle 1996).