Fox Sparrow, Passerella iliaca


Fox Sparrow
Sooty. Fox Sparrows come in four groups that some authorities believe should be recognized as separate species. The birds pictured above and below are Sooty Fox Sparrows, the group that winters in the SF Bay Area, among other places, after nesting along the northwest Pacific Coast up through southern Alaska. They are overall rich brown, with heavy spotting on their underparts, and moderate-sized bicolored bills. Don Roberson provides an excellent analysis of the four Fox Sparrow groups, with additional treatment of many of the recognized subspecies, in this online article, which uses several of the photographs on this page as examples.


Fox Sparrow
Sooty.


Fox Sparrow
Sooty or Slate-colored. Don Roberson suggests that the bird shown above, photographed in Santa Clara County in November, could be either a Sooty, normal in the Bay Area, or a Slate-colored Fox Sparrow of the subspecies altivagans. Slate-coloreds nest in the Rockies and the mountains of the Great Basin, and winter mostly in Southern California and the southwest. They typically show more contrast than Sooties, with heads and backs more gray than brown, and more rusty-colored tails;  they also have relatively small bills, and are less spotted underneath. The altivagans subspecies, which breeds in the interior of British Columbia, has more brown in the back and underparts than other Slate-colored subspecies and so is nearest to the Sooty group in appearance. The bird above does show more gray in the head and a more rusty tail than the typical Sooty, but the spotting pattern is nearly identical with that of the bird shown above it, which is undoubtedly a Sooty.
 


Fox Sparrow
Sooty. This Sooty Fox Sparrow, like the ambiguous bird pictured just above, shows more contrast than the uniformly rich brown of the birds in the top two photos -- more gray in the head, and a bit more red in the tail coverts. The very heavy spotting supports treating the bird as a Sooty.


Fox Sparrow
Red. The photos above and below show Red Fox Sparrows, the group that nests from
central Alaska across northern Canada, and winters mostly in the eastern US. The bird above
was photographed in June in Nome, Alaska, at the northern edge of the Fox Sparrow's
range. It shows an extreme example of the contrast between gray and rufous that characterizes
this group, especially on the head. The bird below, a relatively rare Red Fox Sparrow
wintering in Northern California, has the same distinctive rufous auriculars surrounded by
gray, but has more brown feathering, intermediate between rufous and gray, notably in the
crown and nape. The bills of most Red Fox Sparrows are bi-colored gray and yellow as
in the Sooty and Slate-colored groups, but the bill of the Alaskan bird above is gray all
over, like the larger bill of the Thick-billed Fox Sparrow, see further down the page.


Fox Sparrow
Red.

Fox Sparrow
Thick-billed. The Thick-billed group of Fox Sparrows breed in the Sierras in eastern California, where I see them and hear them singing constantly in early summer when I visit there. Their most striking distinguishing feature is a much larger bill, which is gray all over, where the other three groups have smaller bills with yellow lower mandibles and upper mandibles gray with yellow at the base. Thick-billed Fox Sparrows have a gray head, mantle and underpart spots contrasting with brown wings and tail, and like the Slate-colored their spotting is less extensive is than the Sooty's.


Fox Sparrow
Thick-billed.


Fox Sparrow
Thick-billed.


Fox Sparrow
Thick-billed.