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The many described subspecies of the Fox Sparrow (Passerella iliaca) have been parsed into four groups, the Red (iliaca group, two or three subspecies), Sooty (unalaschcensis group, seven subspecies), Thick-billed (megarhyncha group, five subspecies) and Slate-colored (schistacea group, four subspecies). Intermediate populations and contact areas between these groups play a role in answering the question whether any of the groups should be considered separate species. P. i. canescens of the Slate-colored group shows genetic characters of both the Slate-colored and Thick-billed groups. As currently classified it comprises two disjunct populations, one breeding in the White Mountains of California and Nevada, the other in the Toiyabe Range of central Nevada. We analyzed the vocalizations and bill sizes of these two populations to see if this might shed light on their taxonomic relationships. Our analyses of song, call, and bill measurements, along with a re-examination of previously published morphologic and genetic data, suggest that the two disjunct populations currently assigned to P. i. canescens represent different subspecies: the central Nevada population P. i. schistacea (in the Slate-colored group) and the White Mountains population P. i. megarhyncha (in the Thick-billed group), thus eliminating P. i. canescens as a synonym. Our findings may have implications for any future proposals to split the Fox Sparrow groups into distinct species. If that split results in the Slate-colored and Thick-billed groups assigned to separate species, our results would include the White Mountains population in the Thick-billed species and the central Nevada population in the Slate-colored species. [ABSTRACT FROM AUTHOR]

There are distinct regional differences among the vocalizations of the White-breasted Nuthatch (Sitta carolinensis), but only one subspecies (S. c. carolinensis) has been the subject of published vocal analyses. We used recordings made throughout the ranges of four U.S. subspecies to compare their vocalizations qualitatively and quantitatively, finding that these vocalizations may be categorized in three groups, eastern (S. c. carolinensis), interior west (S. c. nelsoni and S. c. tenuissima), and Pacific (S. c. aculeata). All four subspecies sing a simple song consisting of an evenly spaced series of overslurred notes. The rate of this song varies from <5 notes/sec to >12 notes/sec. The pitch of these songs increases from east to west, being lowest in S. c. carolinensis and highest in S. c. aculeata. Sitta c. aculeata also has an additional song unique to that taxon consisting of a series of sharply slurred, evenly spaced notes that fall, then rise, and then fall in pitch. Both S. c. carolinensis and S. c. aculeata frequently give a simple call note that is very distinctly and rapidly modulated; it is significantly higher in pitch in S. c. aculeata than in S. c. carolinensis. Neither interior subspecies makes a similar call. Both interior subspecies commonly give two calls absent from the repertoires of S. c. carolinensis and S. c. aculeata, one consisting of tightly paired notes given at a constant pace, the other a very rapid, unevenly spaced series of single notes given in short bursts. We found no diagnostic differences between the two interior subspecies in either song or calls. [ABSTRACT FROM AUTHOR]

The article discusses the lack of recovery manifested by the Yellow-Billed Magpie from the West Nile Virus in California's Central Valley following its outbreak in 2005. It states that the population of the species was recorded to be lower by 62% on Christmas Bird Counts which is considered comparable to 22-83% declines for Breeding Bird Survey routes. It mentions that the species has already been uprooted in some localized areas in southern California and the Coast range even prior to the virus outbreak but has remained stable in the Central Valley. It also states that the species' lack of recovery in the region might be due to the continued presence of the virus in the Valley and the absence of seropositive birds in magpies.

The article discusses results of a survey made for the Purple Martin, Progne subis, and other cavity-nesting birds on a portion of Tejon Ranch in the Tehachapi Mountains in California during summer 2010. About 23 nesting pairs of Purple Martins have been discovered, all using cavities in big Valley Oaks, Quercus lobata, at or near the tops of ridges in open savanna settings. The most plentiful other cavity nester in the area was the Acorn Woodpecker, which was likely to create the cavities used by Purple Martins. The European Starling, Sturnus vulgaris, was seldom found near these nest sites.

The article assesses the winter homes of diurnal raptors in the Central Valley in California to determine the diversity of predator birds in the area. Various diurnal raptors species including the white-tailed kite, bald eagle, and prairie falcon were studied in the valley along 19 roadside survey paths from 2007 to 2010. Results of the study show positive connections of winter homes with the raptors including bald eagles with wetlands and rice fields, prairie falcons with grasslands, and American kestrels with alfaalfa fields.

The article presents a study which shows changes in the winter distribution of the Rough-legged Hawk (Buteo lagopus) in North America. It states that the date from nearly 300 Christmas Bird Count (CBC) circles were used to demonstrate a shift in the winter distribution of the specie in North America from the late 1970s to the early 2000s. Decreases in its abundance were revealed on the east and west coast and throughout the southern portion of this species' winter range, while its abundance increased in the northern portions of the Great Plains. The distributional shift was associated with a decrease in the number of December days with substantial snow cover in the Northern Great Plains and an increase in the winter abundance of the Red-tailed Hawk (Buteo jamaicensis).

The article reports on an interspecific feeding behavior of birds observed when an adult Pygmy Nuthatch (Sitta pygmaea) bird was feeding nestlings of a Mountain Bluebird (Sialia currucoides) and removing fecal sacs from their nests near Prosser Creek Reservoir in Nevada County, California.

The article discusses the observations of the authors which suggested hybridization between the Western Tanager and Summer Tanager. The authors conclude that the observations include evidence of such hybridization but they cannot rule the possibility that the young species observed were the offspring of a male Western Tanager due to the absence of specimens or photographs. They mention that the apparent lack of visible wingbars on the young birds suggests that they were hybrids since this characteristic should be seen on fledgling Western Tanagers.

The article presents the message of the President of the Western Field Ornithologists which discusses the future of field ornithology enhanced by a substantial Scholarship Fund allowing young aspiring field ornithologists to attend conferences and participate in expeditions led by top ornithologists. It mentions past recipients of the scholarship fund which includes John Garrett who served as eBird editor for Los Angeles county, Ioana Seritan who was voted American Birding Association's 2013 Young Birder of the year, and Marcel Such who founded the boulder City Teen Naturalists organization.