Slate-colored Fox Sparrow
Encyclopedia
The Slate-colored Fox Sparrow (Passerella (iliaca) schistacea) group comprises the Rocky Mountain taxa in the genus
Passerella. It is currently classified as a "subspecies group"
within the Fox Sparrow
pending widespread acceptance of species status.
It has long been suspected to be a separate evolution
ary lineage due to morphological
distinctness (Swarth 1920). More recently, it has been split into the present clade
and the Thick-billed Fox Sparrow
. These are morphologically quite similar, but can be readily distinguished according to mtDNA sequence
and haplotype
data (Zink 1994). However, these results were considered tentative (Rising & Beadle 1996) until more molecular data and apparent lack of wide-ranging hybridization coupled with ecological differences and adaptation
s led to confirmation of their distinctiveness (Zink & Kessen 1999); this group appears to be most closely related to the Red Fox Sparrow
s (Zink & Weckstein 2003 contra Zink 1996), judging from biogeography
.
It is found to breed in mountaineous regions from the interior of northwest British Columbia
to Nevada
and eastern California
(Rising & Beadle 1996). It is a tiny-billed bird with a gray head and mantle, brown wings, brown breast streaks, and a russet tail.
, it is differentiated into some morphologically recognizable allopatric populations, which are still genetically indistinguishable due to their recent evolution
(Zink 1994).
However, the handful or so subspecies in this complex are poorly differentiated even morphologically for the most part; a two-subspecies arrangement recognizing the rather distinctive altivagans (the northern form) as distinct from the southern populations (schistacea) might be more reasonable (Rising & Beadle 1996). As with Red and Sooty Fox Sparrows, Slate-coloreds also prefer to build their nests on the edges of wet habitat but are much less picky about in which plant they build. Their call note is sharp klink according to Rising & Beadle (1996), or "a sharp smack, like Sooty and Red populations" according to Sibley (2000).
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Passerella. It is currently classified as a "subspecies group"
within the Fox Sparrow
Fox Sparrow
The Fox Sparrow is a large American sparrow. It is the only member of the genus Passerella, although some authors split the genus into four species .-Taxonomy:...
pending widespread acceptance of species status.
It has long been suspected to be a separate evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
ary lineage due to morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
distinctness (Swarth 1920). More recently, it has been split into the present clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
and the Thick-billed Fox Sparrow
Thick-billed Fox Sparrow
The Thick-billed Fox Sparrow group comprises the peculiarly large-billed Sierra Nevadan taxa in the genus Passerella...
. These are morphologically quite similar, but can be readily distinguished according to mtDNA sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
and haplotype
Haplotype
A haplotype in genetics is a combination of alleles at adjacent locations on the chromosome that are transmitted together...
data (Zink 1994). However, these results were considered tentative (Rising & Beadle 1996) until more molecular data and apparent lack of wide-ranging hybridization coupled with ecological differences and adaptation
Adaptation
An adaptation in biology is a trait with a current functional role in the life history of an organism that is maintained and evolved by means of natural selection. An adaptation refers to both the current state of being adapted and to the dynamic evolutionary process that leads to the adaptation....
s led to confirmation of their distinctiveness (Zink & Kessen 1999); this group appears to be most closely related to the Red Fox Sparrow
Red Fox Sparrow
Red Fox Sparrow is the collective name for the most brightly colored taxa in the American sparrow genus Passerella, the Passerella iliaca iliaca group.-Taxonomy:...
s (Zink & Weckstein 2003 contra Zink 1996), judging from biogeography
Biogeography
Biogeography is the study of the distribution of species , organisms, and ecosystems in space and through geological time. Organisms and biological communities vary in a highly regular fashion along geographic gradients of latitude, elevation, isolation and habitat area...
.
It is found to breed in mountaineous regions from the interior of northwest British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
to Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
and eastern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
(Rising & Beadle 1996). It is a tiny-billed bird with a gray head and mantle, brown wings, brown breast streaks, and a russet tail.
Subspecies
Like all "Fox Sparrow" subspeciesSubspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
, it is differentiated into some morphologically recognizable allopatric populations, which are still genetically indistinguishable due to their recent evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
(Zink 1994).
However, the handful or so subspecies in this complex are poorly differentiated even morphologically for the most part; a two-subspecies arrangement recognizing the rather distinctive altivagans (the northern form) as distinct from the southern populations (schistacea) might be more reasonable (Rising & Beadle 1996). As with Red and Sooty Fox Sparrows, Slate-coloreds also prefer to build their nests on the edges of wet habitat but are much less picky about in which plant they build. Their call note is sharp klink according to Rising & Beadle (1996), or "a sharp smack, like Sooty and Red populations" according to Sibley (2000).
- schistacea Baird, 1858:
- Breeds from Crowsnest PassCrowsnest PassCrowsnest Pass is a high mountain pass across the Continental Divide of the Canadian Rockies on the Alberta/British Columbia border.-Geography:...
(British Columbia) and Waterton Lakes Park (SW AlbertaAlbertaAlberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...
) south through the Great BasinGreat BasinThe Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...
mountain ranges. Patchily distributed to wards the southern end of its range, it ranges as far as northern Nevada (Humboldt CountyHumboldt County, NevadaHumboldt County is a county located in the U.S. state of Nevada. As of 2007, the population was estimated to be 18,052. Its county seat is Winnemucca.The county was the site of an arrest in 2000 that led to the U.S. Supreme Court decision Hiibel v...
, Elko County), Fort Bridger, WyomingFort Bridger, WyomingFort Bridger is a census-designated place in Uinta County, Wyoming, United States. The population was 400 at the 2000 census. The town takes its name from the eponymous Fort Bridger established in 1842.-Geography:...
, and Cochetopa Creek (W ColoradoColoradoColorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
). Moves coastwards in winter, occurring mainly in S California.(Weckstein et al. 2002) - The nominate subspecies of the group, its head and back are slate grey, with a brown wash on the back. Wings, rump, tail, crown and underside spotting are a rich darkish brown, somewhat more rusty on the tail (Rising & Beadle 1996).
- altivagans RileyJoseph Harvey RileyJoseph Harvey Riley was an American ornithologist.Born in Falls Church, Virginia, Riley was employed at the Smithsonian Institution from 1896 until his death, becoming Associate Curator of the Division of Birds in 1932.-Sources:*...
, 1911:
- Breeds inland from C British Columbia to the area of Crowsnest Pass. In winter, mainly in the Cascade RangeCascade RangeThe Cascade Range is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades...
and Sierra Nevada, California, and coastal areas to the southwest of this south to northernmost MexicoMexicoThe United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
.(Weckstein et al. 2002) - Overall similar to schistacea, but back noticeably brown and wings and tail with pronounced rusty wash. Altogether, intermediate between schistacea and the Eastern Fox Sparrow (P. (iliaca) iliaca) in morphology, but well distinguished from latter by vocal and molecular characters (Rising & Beadle 1996). Considerable variation in this population suggests some hybridization with the Sooty Fox SparrowSooty Fox SparrowThe Sooty Fox Sparrow contains the darkest-colored taxa in the genus Passerella. It is currently classified as a "subspecies group"within the Fox Sparrow pending wider-spread acceptance of species status...
subspecies fuliginosa and the Yukon Fox Sparrow, as well as intergradationIntergradationIn zoology, intergradation is the way in which two distinct subspecies are connected via areas where populations are found that have the characteristics of both...
with schistacea (around BanffBanff, AlbertaBanff is a town within Banff National Park in Alberta, Canada. It is located in Alberta's Rockies along the Trans-Canada Highway, approximately west of Calgary and east of Lake Louise....
) and the doubtfully distinct olivacea (Weckstein et al. 2002).
- canescens Swarth, 1918:
- Breeds in mountain ranges in C Nevada, notably the Shoshone MountainsShoshone Mountainsalso located in Nye County.The Shoshone Mountains, in central Nevada, make up one of the longest mountain ranges in the state. The range runs in a north-south direction, mostly in Nye County, but also occupies part of Lander County...
, and the ToiyabeToiyabe RangeThe Toiyabe Range is a range of mountains in central Nevada in the western United States. It starts in northwestern Nye County north of Tonopah, Nevada and runs approximately 120 miles north-northeast through eastern Lander County, making it the second longest range in the state...
, and Monitor RangeMonitor RangeThe Monitor Range is located in south-central Nevada in the United States. The range lies west and northwest of the Hot Creek Range and north of Highway 6 in Nye County, and extends for approximately 106 miles into Eureka County at its northern end.The Forest Service is in charge of 83.6% of the...
s, and the White MountainsWhite Mountains (California)The White Mountains of California are a triangular fault block mountain range facing the Sierra Nevada across the upper Owens Valley. They extend for approximately as a greatly elevated plateau about wide on the south, narrowing to a point at the north, with elevations generally increasing...
, California. Winters in the California-Arizona-Mexico border area.(Weckstein et al. 2002) - Similar to schistacea sensu stricto and doubtfully distinct from it; somewhat greyer overall (Rising & Beadle 1996).
- olivacea Aldrich, 1943:
- Breeds from the NelsonNelson, British ColumbiaNelson is a city located in the Selkirk Mountains on the extreme West Arm of Kootenay Lake in the Southern Interior of British Columbia, Canada. Known as "The Queen City", and acknowledged for its impressive collection of restored heritage buildings from its glory days in a regional silver rush,...
area (British Columbia) south along the E slopes of the Cascade Range probably to N IdahoIdahoIdaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
and NW MontanaMontanaMontana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
, reaching east as far as the Blue MountainsBlue Mountains (Oregon)The Blue Mountains are a mountain range in the western United States, located largely in northeastern Oregon and stretching into southeastern Washington...
of OregonOregonOregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
. In winter, migrates to California (Tehama County, Piute MountainsPiute MountainsThe Piute Mountains are found in southeastern California, in the Mojave Desert. The range crosses Interstate 40 at Mountain Springs Summit, 2,770 feet above sea level....
) and the Sierra JuárezSierra JuárezSierra de Juárez is a mountain range on the Baja California Peninsula, of Baja California, Mexico. It is part of the Peninsular Ranges. The Laguna Mountains of California lie to the north and the Sierra San Pedro Mártir lies to the south....
in N Mexico.(Weckstein et al. 2002) - Doubtfully distinct from schistacea sensu stricto (Rising & Beadle 1996). Intermediate between this form and the fulva Thick-billed Fox SparrowThick-billed Fox SparrowThe Thick-billed Fox Sparrow group comprises the peculiarly large-billed Sierra Nevadan taxa in the genus Passerella...
s ; darker and browner than the first, and brown olive- rather than red-tinged; bill small as in schistacea with which it intergrades.(Weckstein et al. 2002)
- swarthi Behle & Selander, 1951:
- Breeds from Bannock County and Bear Lake County, Idaho, through mountain ranges in UtahUtahUtah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
south to Sanpete County. Winter range unknown.(Weckstein et al. 2002) - A very grey form with heavy breast pattern, but as it apparently intergrades with schistacea and canescens (Weckstein et al. 2002) doubtfully distinct from the former (Rising & Beadle 1996).
External links
- Photo-High Res; Article – "San Diego Birding Pages"
