Prepared by David F. DeSante
Posted 10.3.99
Contact: CPIFPlans at prbo dot org
See the introduction to Appendix 1 for explanations of codes and abbreviations.
Stat: R West: fS,ifW. East: fR.
Dist: T West: N:3-10; W:3-10. East: N:B-10; W:B-10.
Sign: CONT-1. Ssp. orius northern Sierra north of Yosemite region-
PAC-7; hyloscopus southern Sierra from about Yosemite southward
- CAL-10.
Because orius is replaced by harrisi in the western portions
of Washington, Oregon, and northwestern California, its Sierran range is
of greater IMportance than for most PAC-7 subspecies. Overall, the Sierra
is of substantial importance for both subspecies.
Hab: R: 3-MHW,MHC,PPN,MCN,JPN,LPN,SCN,ASP,EPN,MRI,[RSP]; 2-DFR,RFR.
F: 3-MHW,MHC,PPN,MCN,JPN,LPN,SCN,ASP,EPN,MRI,[RSP]; 2-DFR,RFR.
F: Mature timber and dead snags or trees of moderate to large size are more important than tree species.
Abundance: BBS: 15 routes; 1.63 birds/route. MAPS: 0.69 ad/600 nh
Trends: BBS: LS; 0.9% per year
Demographics: MAPS: Prod. index: 37.2% yg.
Potential risks and suggested causes of population trends: Hairy Woodpeckers prefer rather mature forests with large trees, so logging operations can be detrimental. Pesticide use on forest insect outbreaks could also be a risk, as could the removal of snags. Loss of riparian habitat may also be a risk. Overall they seem to face fewer risks than Red-breasted Sapsuckers but more than White-headed Woodpeckers; and their population trend is intermediate between the decline of sapsuckers and the increase of White-heads.
WHITE-HEADED WOODPECKER - Picoides albolarvatus
Stat: R West: fR. East: rR,rT.
Dist: T West: N:4-8; W:4-8. East: N:7-9 T:7-10, W:7-9.
Sign: PAC-7. Ssp. albolarvatus - PAC-7. This species may be more common in the Sierra than in any other part of its range. Thus, the Sierra is of great importance to the species' overall population.
Hab: R: 3-PPN,MCN,JPN,EPN; 2-MHC,RFR,LPN,[RSP].
F: 3-PPN,MCN,JPN,EPN; 2-MHC,RFR,LPN,[RSP].
F: Prefers mature mixed coniferous forest with trees of moderate to large size, but also occurs commonly in more open ponderosa and jeffrey pine forest and less commonly in more closed red fir forest and eastside jeffrey pine forest.
Abundance: BBS: 15 routes; 1.81 birds/route. MAPS: 0.66 ad/600 nh
Trends: BBS: PI; 3.7% per year
Demographics: MAPS: Prod. index: 4.1% yg.
Potential risks and suggested causes of population trends: This species prefers more open forest than either Red-breasted Sapsuckers or Hairy Woodpeckers and its population trend shows an increase. Logging operations are, thus, probably beneficial to this species. Pesticide use on forest insect outbreaks could be a risk, as could the removal of snags. Comparative study of the woodpeckers as a function of management practice could reveal important information.
BLACK-BACKED WOODPECKER - Picoides arcticus
Stat: R West: luR,xT. East: xT.
Dist: NC West: N:7-9; T:4-9; W:7-9. East: T:8-10.
Sign: CAN/WMT-3. This species occurs in western mountains only south to central California and northern Wyoming and is generally uncommon everywhere. Thus its Sierran range may be more important to the species than most CAN/WMT-3 species. The central and northern Sierra seems to be the metropolis of the species range in California and thus is extremely important for the entire California population.
Hab: R: 3-LPN,(SCN).
F: 3-LPN,(SCN); 2-RFR.
F: Prefers lodgepole pines and, less commonly, red firs, white pines, and mountain hemlocks. Contrary to the WHR, I have not found the species in subalpine conifers. They are partial to areas infected with larval bark insects and often occur most commonly in recently defoliated or burned areas.
Abundance: BBS: 4 routes; 0.09 birds/route. MAPS: 0.01 ad/600 nh
Trends: BBS: UN; 14.9% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Despite the fewroutes on which this species has been recorded, the increasing population trend may be real. If so, the increase could be due the relatively recent outbreaks of larval bark beetles that may have been promoted by recent occurrences of fire and drought. Pesticide use on forest insect outbreaks could be an important risk, but snag removal may not be a problem as Black-backs almost invariably nest in live trees. This also could account for the lack of a decrease. This unique species deserves concerted study.
NORTHERN FLICKER - Colaptes auratus
Stat: SDM West: fS,rT,ifW. East: fS,rT,ifW.
Dist: T West: N:F-10; T:F-13; W:F-5. East: N:B-10; T:B-13; W:B-8.
Sign: CONT-1. Spp. collaris - WEST-4.
Hab: R: 3-MHW,MHC,PPN,MCN,JPN,ASP,EPN,MRI,RSP; 2-DFR,LPN,PJN,JUN.
F: 3-MHW,MHC,PPN,MCN,JPN,ASP,EPN,MRI,PAS,RSP; 2-DFR,LPN,PJN,JUN,WTM,
MCP.
F: Extremely widespread but always requires some open area for ground foraging.
Abundance: BBS: 17 routes; 5.93 birds/route. MAPS: 0.28 ad/600 nh
Trends: BBS: DS; -0.5% per year
Demographics: MAPS: Prod. index: 32.5% yg.
Potential risks and suggested causes of population trends: Logging operations may have little effect on flickers which often tend to avoid forested areas, both closed and open. Similarly, pesticide use on forest insect outbreaks is unlikely to be a risk as flickers do not seem to concentrate at such outbreaks. Snag removal remains a risk. Otherwise, risks are hard to suggest for this adaptable species. And indeed, the flicker is one of only five Sierran landbirds that seems to have a definitely relatively stable population trend. Productivity seems to be similar to other woodpeckers.
PILEATED WOODPECKER - Dryocopus pileatus
Stat: R West: uR,rT. East: xT.
Dist: T West: N:3-7; T:3-9; W:3-7. East: T:7-8.
Sign: CAN/EUS-3. Ssp. picinus - PAC-7. The Sierra represents an important part of the species' California range.
Hab: R: 3-MHC,PPN,DFR,MCN,JPN,RFR,(LPN); 2-MHW.
F: 3-MHC,PPN,DFR,MCN,JPN,RFR,(LPN); 2-MHW.
F: Generally requires old-growth forest with an Abundance of large, decayed, standing and fallen timber. The size and state of the trees seems to be more important than tree species.
Abundance: BBS: 11 routes; 0.59 birds/route. MAPS:
Trends: BBS: DT; -2.6% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: This species may be changing its habitat requirements in the Sierra, as it has done over most of the continent, to become more tolerant of second growth forests. Regardless, however, the forests still need to be relatively dense and closed and contain considerable dead wood. It is not surprising, therefore, that this species continues to show a decreasing tendency. Pesticide use on forest insect outbreaks could be a risk and snag removal is most definitely a risk.
OLIVE-SIDED FLYCATCHER - Contopus borealis
Stat: NTM West: fS,uT. East: uS,rT.
Dist: T West: N:3-9; T:F-10. East: N:7-9; T:B-10.
Sign: CAN/WMT-3.
Hab: R: 3-MHC,DFR,MCN,JPN,RFR,LPN.
F: 3-MHC,DFR,MCN,JPN,RFR,LPN; 2-MHW,PPN,SCN,ASP,EPN,MRI.
Sp: Requires very tall trees with dead perches at their very top. If such are present, will occur atop trees in dense forests or more open woodlands. Because of their height requirements, tall conifers generally must always be present.
Abundance: BBS: 17 routes; 12.37 birds/route. MAPS: 0.29 ad/600 nh
Trends: BBS: DD; -3.8% per year ***
Demographics: MAPS:
Potential risks and suggested causes of population trends: Here is another species that is definitely decreasing in the Sierra and over its entire range (DeSante and George 1994). Marshall (1988) suggested that deforestation on its wintering grounds is the probable cause and I concur with this assessment. Not only has its Central American wintering grounds (where Sierran birds probably winter) been heavily impacted, the metropolis of its winter range on the East slope of the Andes in northern South America lies in the heart of the coca production area of South America. This species may, therefore, be an indirect casualty of cocaine abuse. Loss of old-growth forests and snags on the breeding range may also be a risk as might the effects of pesticides on large flying insects on both the breeding and wintering ranges. This is a species that must be closely monitored. It is a federal Candidate 2 species.
WESTERN WOOD-PEWEE - Contopus sordidulus
Stat: NTM West: cS,uT. East: cS,rT.
Dist: T West: N:3-9; T:F-10. East: N:B-9; T:B-10.
Sign: WEST-4. Ssp. veliei - WEST-4.
Hab: R: 3-MHW,MHC,PPN,MCN,JPN,RFR,LPN,ASP,EPN,(PJN),MRI; 2-DFR.
F: 3-MHW,MHC,PPN,DFR,MCN,JPN,RFR,LPN,ASP,EPN,(PJN),MRI,RSP.
Sp: Very widespread but requires conspicuous lookout posts in an open mid-story beneath the canopy for foraging. Shuns only the interior of very dense forests but inhabits openings and the edges of such forests. In my experience tends to avoid pinyon-juniper on the East slope.
Abundance: BBS: 17 routes; 22.63 birds/route. MAPS: 2.62 ad/600 nh
Trends: BBS: DD; -2.9% per year ***
Demographics: MAPS: Prod. index: 24.9% yg.
Potential risks and suggested causes of population trends: Here is another decreasing Neotropical migrant that winters virtually entirely in South America. Again, I suspect deforestation on the winter grounds in the area where Sierran birds winter to be the major risk, as the species may be increasing over much of its breeding range (DeSante and George 1994). If the causes of decline of the species in the Sierra lie on the breeding range, they are a mystery to me as I can not easily identify risks that the species might face. A general reduction in the total amount of forested area due to logging is all that comes to mind. Like most flycatchers, its MAPS productivity index is low. However, it is the lowest of the seven Sierran flycatcher sampled by the MAPS program, so maybe something is going on in the Sierra. This is a species to watch.
WILLOW FLYCATCHER - Empidonax traillii
Stat: NTM West: lrS,xT. East: lrS,xT.
Dist: T West: N:4-7; T:4-8. East: N:B-8; T:B-10.
Sign: US-2. Ssp. brewsteri - PAC-7. The brewsteri subspecies is currently classified by the USDI Fish and Wildlife Service as a Federal Candidate 2 species and by the California Department of Fish and Game as an Endangered Species in California. Its population in the Sierra has decreased drastically over the past 50-60 years and it is now on the brink of extinction in the Sierra. The subspecies extimus occurs in the Kern River Valley, just outside of the area covered by this analysis. It is also listed as Endangered in California and has been formally proposed for listing as a Federal Endangered species. Without question, the Willow Flycatcher is the most endangered landbird species in the Sierra.
Hab: R: 3-MRI.
F: 3-WTM,MRI.
Sp: Wedded to willows in the Sierra. Requires large shrubby willows that line slow-moving streams in open meadow situations or that scatter about seeps in moist meadows. Definitely prefers clumps of willows to dense continuous thickets and prefers shrubby rather than arborescent willows.
Abundance: BBS: MAPS: 1.23 ad/600 nh
Trends: BBS:
Demographics: MAPS: Prod. index: 35.6% yg.
Potential risks and suggested causes of population trends: Here is a species that has all but disappeared from the Sierra. The cause for its decline seems clearly to be the browsing of the willows by livestock in the montane meadows that it requires for breeding. Serena (1982) showed that the species does not occur in willows if the lower foliage has been denuded by livestock. In meadows where it does breed, which are always meadows where there is no grazing, the species still seems to be reproducing well. The productivity index for the Sierra from MAPS data (35.6% yg.) is at least as high as those for Western Wood Pewee (24.9%), Hammond's Flycactcher (27.6%), and Dusky Flycatcher (33.0%). The similarity to Dusky Flycatcher is important as the two species often nest side-by-side in nearby willow patches in the same meadows. In the humid coast ranges of Oregon and Washington, Willow Flycatchers have apparently responded well to the red alder thickets that spring up on lower level montane hillsides after clearcutting (pers. observ.). As a result, Willow Flycatchers seem to be doing well in coastal Oregon and Washington, despite the possibility that they may face similar grazing problems in willow meadow habitats there. Because of drier conditions, such growths of red alder do not occur after clearcutting in the Sierra. Moreover, Sierran Willow Flycatchers seem to shun the mountain alder thickets that choke streamsides in wooded areas of the Sierra. Rather, they seem to be entirely wedded to the open clumps of willows in Sierran meadows. The complete elimination of grazing in montane meadows in the Sierra may offer the only hope for preserving this vanishing part of the Sierran avifauna.
HAMMOND'S FLYCATCHER - Empidonax hammondii
Stat: NTM West: cS,uT. East: rT.
Dist: T West: N:3-8; T:F-10. East: T:B-10.
Sign: WMT-6.
Hab: R: 3-MHC,(PPN),DFR,MCN,(JPN),RFR,RSP; 2-MRI.
F: 3-MHW,MHC,(PPN),DFR,MCN,(JPN),RFR,MRI,RSP.
Sp: Requires deeply shaded foliage beneath the canopy of large conifers. Favored trees are white and red firs, sugar pines, Douglas firs, and sequoias. Contrary to WHR I find them much less commonly in ponderosa pines and jeffrey pine forests. Occurs in moderately dense late-stage second growth as well as old growth but always requires considerable canopy closure.
Abundance: BBS: 14 routes; 6.05 birds/route. MAPS: 2.68 ad/600 nh
Trends: BBS: DS; -0.2% per year The definitely stable BBS trend for this species may be offset partially by a decrease in unidentified Empidonax over the years, as observers became more familiar with the diagnostic calls of Hammond’s and Dusky Flycatchers.
Demographics: MAPS: Prod. index: 27.6% yg.
Potential risks and suggested causes of population trends: Because Hammond's Flycatchers prefer dense closed forests at mid-elevations in the Sierra, one would expect that logging of all kinds would be detrimental to their existence. Thus the definitely stable trend for this species comes as a surprise. One would also expect that, more than most species, they would also be subject to similar risks in the tropics. Problems, however, do not seem to be widespread on the wintering grounds as the species shows high annual survival rates. What is it that allows this species to survive and even thrive in Sierran and, apparently, Mexican forests as well? Or could the apparent increasing trend be completely an artifact of recent advances in the understanding of the vocalizations of this species? Indeed, the most common call of this species, a sharp Pygmy Nuthatch-like "pip" or "peek", was not widely appreciated by birders until the 1980s. Controlled studies of the population trends in this species are needed.
GRAY FLYCATCHER - Empidonax wrightii
Stat: NTM West: lrS?,rT. East: luS,uT.
Dist: SW,TE West: N:7?; T:4-7. East: N:B-8; T:B-8.
Sign: RM/GB-8. Gray Flycatchers are generally rare on the east slope of the Sierra, becoming more common east of the Sierran escarpment. They may also nest on the Kern Plateau on the west slope of the southern Sierra. Thus, the Sierra is less important to their overall population than for other RM/GB-8 species.
Hab: R: 3-PJN,JUN; 2-[EPN].
F: 3-PJN,JUN; 2-[EPN].
Sp: Requires large, dense-foliaged shrubs, usually sagebrush, bitterbrush, or junipers, sometimes amidst very scattered pinyons or eastside jeffrey pines.
Abundance: BBS: MAPS: 0.24 ad/600 nh
Trends: BBS:
Demographics: MAPS: Prod. index: 77.2% yg.
Potential risks and suggested causes of population trends: The high productivity index for this species is an artifact of the near lack of breeding habitat at the single MAPS station at which it occurs and the attractiveness of the willow habitat there to dispersing juveniles. No obvious threats come to mind other than grazing on its breeding habitat (it is unclear how this species responds to grazing) and degradation of its northern Mexican brushland wintering habitat.
DUSKY FLYCATCHER - Empidonax oberholseri
Stat: NTM West: fS,rT. East: fS,uT.
Dist: T West: N:4-10; T:F-10. East: N:7-10; T:B-10.
Sign: WMT-6.
Hab: R: 3-MHC,PPN,MCN,JPN,LPN,SCN,ASP,EPN,MRI,MCP; 2-RFR.
F: 3-MHC,PPN,MCN,JPN,LPN,SCN,ASP,EPN,MRI,MCP; 2-DFR,RFR.
Sp: At higher elevations, prefers open or broken lodgepole or subalpine forest particularly about meadows, clearings, and brushy slopes. At lower elevations, where perhaps less abundant, prefers montane chaparral intermixed with scattered trees or open forest. Also utilizes willow thickets, especially drier ones than preferred by Willow Flycatchers, riparian habitats, especially more open ones than preferred by "Western" Flycatchers, and aspen forests.
Abundance: BBS: 15 routes; 4.34 birds/route. MAPS: 9.35 ad/600 nh
Trends: BBS: PI; 6.1% per year As with Hammond's Flycatcher, the observed trend for Dusky Flycatcher may have been distorted by the decreasing trend in unidentified Empidonax.
Demographics: MAPS: Prod. index: 33.0% yg.
Ann. surv. rate: 0.645 (0.147);
Cap. prob.: 0.546 (0.139).
Potential risks and suggested causes of population trends: Because this species prefers open, broken forest and scattered shrub cover, we might expect that some forestry practices might be beneficial to it. Furthermore, it seems to be more tolerant of grazing in montane meadows than the Willow Flycatcher as it breeds in willows in grazed meadows where Willow Flycatchers are absent. Indeed, I cannot easily identify any serious risks to it in the Sierra. Because of potential confusion of Hammond's and Dusky Flycatchers on BBS routes, especially during the early years of the Program, the increasing tendency of the species may not be accurate. However, it is worth noting that population levels of the species have remained remarkably stable (despite marked year to year variations as result of snowpack [DeSante 1990]) for 17 years in a 1-km2 subalpine study area in the Hall Natural Area of the Inyo National Forest DeSante pers. observ.).
PACIFIC-SLOPE FLYCATCHER - Empidonax difficilis
Stat: NTM West: uS,rT. East: rT?.
Dist: T West: N:F-6; T:F-10. East: T:B-10?.
Sign: PAC-7. Ssp. difficilis - PAC-7. The "Western Flycatcher" has been split recently into two essentially allopatric species, the Pacific- slope Flycatcher on the West slope and the Cordilleran Flycatcher, which is presumably the species breeding in small numbers on the East slope. The status of Pacific-slope Flycatchers on the East slope is unknown. Presumably, most East slope migrants are Cordilleran Flycatchers but Pacific-slope Flycatchers from north of California probably migrate in substantial numbers east of the Sierra. Generally, however, "Western" Flycatchers of any kind are rare migrants on the east slope of the Sierra. Because the Pacific-slope Flycatcher is relatively uncommon in the Sierra, its importance there is less than some other PAC-7 species.
Hab: R: 3-MHC,PPN,MCN,JPN,LPN,SCN,ASP,EPN,MRI,MCP; 2-RFR.
F: 3-MHC,PPN,MCN,JPN,LPN,SCN,ASP,EPN,MRI,MCP; 2-DFR,RFR.
Sp: Requires dense, shady, moist mixed forest usually with maple and Douglas fir, or dense, shady forested canyonbottoms, often in the vicinity of running water. Requires a bank, structure, or tree roots or stump against which to place its nest.
Abundance: BBS: 9 routes; 0.84 birds/route. MAPS: 2.25 ad/600 nh
Trends: BBS: IT; 2.5% per year
Demographics: MAPS: Prod. index: 41.5% yg.
Potential risks and suggested causes of population trends: Risks include logging of dense, shady, mature Douglas fir forests, but the streamside canyon-bottom nature of its preferred habitat may provide a large measure of safety from logging operations. Deforestation and fragmentation of tropical winter habitat and pesticide use are also risks. MAPS productivity seems to be fine for a flycatcher, and, indeed, the species shows an increasing tendency.
CORDILLERAN FLYCATCHER - Empidonax occidentalis
Stat: NTM West: ?? East: rS,rT.
Dist: NC? West: ?? East: N:8-9; T:B-10.
Sign: RM/GB-8. See above under Pacific-slope Flycatcher. The status of the Cordilleran Flycatcher on the West slope is unknown. It is likely a very rare transient there if it occurs at all. To my knowledge, Cordilleran Flycatchers have not been recorded nesting south of Mammoth Lakes but this needs to be confirmed. Because this species is so rare in the Sierra, its importance there is less than some other RM/GB-8 species.
Hab: R: 3-MHW,MHC,PPN,DFR,MRI,RSP.
F: 3-MHW,MHC,PPN,DFR,MRI,RSP.
Sp: Appears to require shady streamside groves of conifers and aspens. Nest requirements probably as in Pacific-slope Flycatcher but more work is needed here.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: I have no idea but suspect that risks would be similar to the Pacific-slope Flycatcher.
BLACK PHOEBE - Sayornis nigricans
Stat: R-SDM West: fR,xT. East: rT.
Dist: T West: N:F-5; T:F-9; W:F-4. East: T:B-10.
Sign: SW-9. Ssp. semiatra - SW-9. Because Black Phoebes are of limited Distribution in the Sierra, the Sierra is not of such great importance to this species as it could be for a SW-9 species.
Hab: R: 3-MRI,RSP.
F: 3-WTM,MRI,(BAR),RSP; 2-PAS.
Sp: Requires structures such as houses, sheds, or bridges for nest sites and, usually, the presence of water. even artificial water supplies.
Abundance: BBS: 2 routes; 0.03 birds/route. MAPS: 0.27 ad/600 nh
Trends: BBS: UN; 17.32% per year
Demographics: MAPS: Prod. index: 60.1% yg.
Potential risks and suggested causes of population trends: This species has adapted well to the human presence. Indeed, BBS data shows it increasing dramatically, though the trend cannot be classified due to low sample size. The species' MAPS productivity index also seems to be good for a flycatcher. Pesticide use, particularly around human settlements, may be a risk.
Stat: SDM West: rT,rW. East: rS?,rT.
Dist: T West: T:F-10; W:F-2. East: N:B-8?, T:B-10.
Sign: WEST-4. Ssp. saya - WEST-4. Say's Phoebes are rare transients and probably rare breeders on the East slope of the Sierra proper, but become uncommon breeders and fairly common transients east of the east base of the Sierran escarpment. They also breed in the arid lower foothills on the west slope of the Sierra. Because they are so rare in the Sierra, the Sierra is much less important to their overall population than it is for most WEST-4 species.
Hab: R: 3-PJN,JUN,MCP,BAR.
F: 3-PJN,JUN,PAS; 2-MCP,BAR.
Sp: Requires open country with scattered bushes, rocks, structures, or fences for lookout perches. Also requires rocks, cliffs, banks, or structures for nest placement.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: This species generally prefers remote arid breeding grounds and seems secure from virtually all risks on the breeding grounds. Widely-spaced ranch structures offer satisfactory nesting sites. I have no idea what is happening to this species on the margins of the Sierra where it occurs, but I am convinced that the species is declining in the Bay Area in winter. What's happening?
ASH-THROATED FLYCATCHER - Myiarchus cinerascens
Stat: NTM West: fS,xT. East: rS?,rT.
Dist: TW,SE West: N:F-5; T:F-10. East: N:B-7; T:B-8.
Sign: WUS-5. Ssp. cinerascens - WUS-5. Because this is primarily a species of the foothills, its Sierran range is less important to the species than many other WUS-5 species. This species apparently does not breed on the east slope of the Sierra except perhaps in the southern part. More information is needed regarding this.
Hab: R: 3-PJN,JUN,[MHW],[MHC].
F: 3-PJN,JUN,[MHW],[MHC].
Sp: Prefers open oak or pine-oak woodland (usually blue or live oaks and digger pines) with a scattered shrubby understory or chaparral slopes with scattered oaks or pines. Cavity nester.
Abundance: BBS: 6 routes; 0.32 birds/route. MAPS:
Trends: BBS: UN; 4.2% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Loss of oak woodland or pinyon juniper breeding habitat, degradation of its large-insect prey base by pesticides, and usurpation of nesting cavities by starlings are possible risks that are probably not realized. I believe they can evict and dominate starlings (at least at reasonable densities of starlings) and I believe that their rather remote, dry breeding habitat is currently fairly safe from development and pesticides. Pesticide issues on tropical wintering grounds, and loss of winter habitat may be more serious problems. Still, the increasing tendency is probably real.
WESTERN KINGBIRD - Tyrannus verticalis
Stat: NTM West: fS,rT. East: rS.
Dist: T West: N:F-5; T:F-9. East: N:B-7.
Sign: WEST-4. This species primarily breeds in the lower foothills of the west slope and east of the east base of the Sierran escarpment. Thus, the Sierran population is of little importance to this widely Distributed western species.
Hab: R: 3-MHW,MHC,RSP.
F: 3-MHW,MHC,RSP; 2-WTM,PAS.
Sp: Requires open, flat or gently rolling terrain with scattered trees or fences and telephone wires for lookout perches, or open oak woodland (usually valley or blue oaks). Also occurs commonly in tall, open riparian woodland, usually cottonwoods or sycamores.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: Residential and agricultural development of its valley foraging grounds, pesticide use affecting its large-insect prey base, and destruction of arborescent riparian and oak savannah breeding habitat are the obvious risks. Also, pesticide use on its wintering grounds could be an important risk. I believe that the foothill Sierran populations may be decreasing somewhat, but this is just a guess.
LOGGERHEAD SHRIKE - Lanius ludovicianus
Stat: SDM West: rT. East: uS,rW.
Dist: T West: T:F-9. East: N:B-7; W:B-7.
Sign: US-2. This species, however, has become very rare or locally extirpated over most of the eastern U.S., so the proper species' importance might better be WEST-4. Ssp. gambeli west slope (except extreme southern part) and northern portion of the east slope - WUS-5 (although perhaps better represented by a combination of RM/GB-8 and CAL-10); nevadensis central and southern portions of east slope and extreme southern portion of west slope - M/GB-8. AOU (1957) did not recognize nevadensis and included this race in gambeli. If this taxonomy is followed then gambeli is best considered WUS-5. Regardless of taxonomy, Loggerhead Shrikes are only marginal breeders on the east slope of the Sierra (and possibly along the very lowest foothills of the west slope). The Sierra, therefore, constitutes an very unimportant part of their total range. However, because they seem to be declining over large portions of their range, their Sierran populations should be watched.
Hab: R: 3-PJN,JUN.
F: 3-PJN,JUN; 2-WTM,PAS,RSP.
Sp: Prefers arid grassland or other open country habitat with scattered large shrubs or trees for nest sites and fences or telephone wires for lookout perches.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: No population trend data exist for the Sierra. However, populations of this species are declining over most of their range. Risks include loss of habitat to agricultural and residential development and possible decreases in or contamination of the prey base due to pesticides.
PLUMBEOUS VIREO - Vireo plumbeus
Stat: NTM West: East: lrS,rT.
Dist: CSE West: East: N:7-8; T:B-10.
Sign: RM/GB-8. Sierran populations of are very small and unimportant to the total range
Hab: R: 3-EPN,PJN,JUN,MRI; 2-ASP.
F: 3-EPN,PJN,JUN,MRI; 2-ASP,RSP.
Sp: Prefers dry, open stands of jeffrey or pinyon pines and junipers. Also occurs rarely in shady canyon bottoms.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: Virtually nothing is known about this species in the Sierra. Risks, however, are probably similar to Cassin’s Vireo. Like that species, may be increasing in the Sierra.
CASSIN’S VIREO - Vireo cassinii
Stat: NTM West: fS,uT. East: luS,uT.
Dist: TW,NE West: N:3-7; T:F-10. East: N:5-8; T:B-10.
Sign: PAC-7 (but extends east across northern Rockies to western Montana); Ssp. cassinii - PAC-7 (but extends east across northern Rockies to western Montana). Sierran populations are relatively large so Sierra of considerable importance in it range.
Hab: R: 3-MHW,MHC,PPN,JPN,PJN,JUN,MRI; 2-DFR,MCN,RFR,ASP,EPN.
F: 3-MHW,MHC,PPN,JPN,PJN,JUN,MRI; 2-DFR,MCN,RFR,ASP,EPN,RSP.
Sp: On the west slope, prefers rather dry, open forests where black or canyon oaks mix with ponderosa pine or mixed coniferous forest, particularly with open branchwork at low and middle levels. Less common in moist, shady canyonbottoms and red fir forests. On the east slope, prefers dry, open stands of jeffrey or pinyon pines and junipers.
Abundance: BBS: 16 routes; 6.54 birds/route. MAPS: 2.60 ad/600 nh
Trends: BBS: DI; 4.0% per year **
Demographics: MAPS: Prod. index: 30.4% yg.
Potential risks and suggested causes of population trends: Risks include extensive logging, although certain forestry practices might not be deleterious. Like most vireos, seems highly susceptible to cowbird parasitism and nest predation, particularly because males often sing from the nest. Perhaps for this reason, seems to have a relatively low MAPS productivity index, although this could also be caused by relative lack of up-mountain movements of young. All things considered, the definitely increasing population trend of 4.0% per year seems surprising. I can offer no ready explanation for this species population increase, but it seems to be increasing throughout the western U.S. (DeSante and George 1994).
HUTTON'S VIREO - Vireo huttoni
Stat: R West: fR. East:
Dist: T West: N:F-5; W:F-5. East:
Sign: PAC-9 (but also occurs in the Southwest). Ssp. huttoni - PAC-7. Sierran population may be relatively small compared to those in the coast ranges.
Hab: R: 3-MHW,MHC,MRI.
F: 3-MHW,MHC,MRI,RSP; 2-DFR.
Sp: Shows a strong preference for interior live oaks, but occurs to a lesser extent in canyon and blue oaks. Favors rather dense woodland, often with a shrubby understory.
Abundance: BBS: 5 routes; 0.18 birds/route. MAPS:
Trends: BBS: UN; -2.3% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Risks include loss of foothill oak habitat to development and, possibly, cowbird parasitism.
Stat: NTM West: cS,uT. East: cS,rT.
Dist: T West: N:3-8; T:F-10. East: N:B-8; T:B-10.
Sign: CONT-1. Ssp. swainsonii west slope and both northern and southern portions of east slope - WEST-4 (except absent from Great Basin); leucopolius central portion of east slope - RM/GB-8 (but limited to the Great Basin. Populations in the Sierra are large but probably smaller than in other parts of California, particularly the coast ranges.
Hab: R: 3-MHW,MHC,ASP,MRI; 2-PPN,[DFR],[MCN],[RFR],[LPN].
F: 3-MHW,MHC,ASP,MRI,RSP; 2-PPN,DFR,MCN,JPN,[RFR],[LPN],EPN,PJN.
Sp: Generally prefers moist conditions and moderate to dense cover. Reaches greatest abundance in the presence of deciduous trees, particularly aspens, cottonwoods, and alders, and to a lesser extent black oaks and maples. However, can also occur in smaller numbers in coniferous forests that completely lack a broad-leaved element.
Abundance: BBS: 16 routes; 7.63 birds/route. MAPS: 13.33 ad/600 nh
Trends: BBS: LS; 0.8% per year
Demographics: MAPS: Prod. index: 26.3% yg.
Ann. surv. rate: 0.366 (0.090);
Cap. prob.: 0.530 (0.137).
Potential risks and suggested causes of population trends: Risks include forestry practices that tend to make forests more open and remove or limit deciduous trees. Very susceptible to cowbird parasitism. Also, perhaps because males sing from the nest, may be highly susceptible to nest predation. Shows an even lower MAPS productivity index than Cassin’s Vireo. Despite all these risks, BBS data show a likely stable trend. Appears to be increasing throughout the western U.S. (DeSante and George 1994). I can offer no explanation for this stable/increasing trend, except to note the similarities with Cassin’s Vireo.
STELLER'S JAY - Cyanocitta stelleri
Stat: R West: cS,icW. East: cS,icW.
Dist: T West: N:2-10; W:F-9. East: N:B-10; W:B-8.
Sign: WMT-6. Ssp. frontalis - CAL-10. Also occurs in the Cascades of southern and central Oregon. Because of its abundance in the Sierra, the Sierra represents a very important part of this subspecies overall range. However, because it occurs most commonly in the vicinity of human activities, its abundance in the Sierra may be overestimated by casual observation.
Hab: R: 3-MHC,PPN,DFR,MCN,JPN,EPN,RSP; 2-MHW,RFR,LPN,ASP,MRI.
F: 3-MHW,MHC,PPN,DFR,MCN,JPN,EPN,MRI,RSP; 2-RFR,LPN,ASP.
Sp: Occurs in a wide-variety of wooded habitats. Reaches its greatest abundance around locations of human habitation and activity in forested areas.
Abundance: BBS: 17 routes; 21.62 birds/route. MAPS: 0.18 ad/600 nh
Trends: BBS: DD; -1.7% per year **
Demographics: MAPS: Prod. index: 26.1% yg.
Potential risks and suggested causes of population trends: I have no solid explanation for the decreasing trend in this species, except to note that it is mirrored by several other very widespread resident species, most notably Mountain Chickadee. However, because Steller's Jays depend heavily on acorns and pine nuts in winter; perhaps a decrease in acorn production or a general decrease in oaks is responsible.
WESTERN SCRUB JAY - Aphelocoma coerulescens
Stat: R West: cR,rT. East: uR,rT.
Dist: T West: N:F-4; T:F-10; W:F-4. East: N:B-8; T:B-10; W:B-8.
Sign: WUS-5. Ssp. superciliosa - PCAL-11 (but also breeds north to south- central Oregon). This is the breeding race throughout the west slope and on both the northern and southern portions of the east slope of the Sierra; nevadae - RM/GB-8. This is the breeding form on the central eastern slope of the Sierra. Scrub Jays are more common in the lower foothills and valley bottoms west of the Sierra and in the Great Basin country east of the Sierra than in the Sierra proper. Thus the Sierra is somewhat less important overall to these races than are other areas in California. The race nevadae, however, is of very limited distribution in California, so even the very small Sierra populations of this race are important to the species in California.
Hab: R: 3-RSP; 2-MHW,MHC,PJN,JUN,MRI.
F: 3-RSP; 2-MHW,MHC,PJN,JUN,MRI.
Sp: On the west slope prefers dry, open woodland mixed with chaparral, but also inhabits riparian woodlands and adapts readily to residential areas and gardens. The presence, however, of some oaks seems to be a requisite in natural environments as the species depends heavily on acorns. On the east slope it prefers pinyon and juniper habitat and generally shuns human habitations.
Abundance: BBS: 8 routes; 0.79 birds/route. MAPS: 0.01 ad/600 nh
Trends: BBS: UN; -3.2% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: If this species is decreasing, it may be due to a deterioration of the acorn crop, as has been Suggested earlier under Band-tailed Pigeon, Acorn and Lewis' Woodpeckers, and Steller's Jay. The species may be declining recently on the east slope too, perhaps due to poor pinyon nut crops caused by the many recent drought years. Otherwise, I cannot readily identify any risks that this species faces.
PINYON JAY - Gymnorhinus cyanocephalus
Stat: R-SDM West: rS?,irT. East: luS,iuT,iuW.
Dist: S West: N:7? T:4-13. East: N:B-8; T:6-13; W:B-8.
Sign: RM/GB-8. Although this species nests commonly in the pinyon pines east of the eastern base of the Sierran escarpment, they do not seem to nest in the pinyons that clothe the east slope of the Sierra except along the southern part of the east slope. On the west slope, they may also nest on the Kern Plateau. This needs further study, however. At any rate, the Sierra is of less importance to this species than the mountains and flats to the east.
Hab: R: 3-PJN,JUN.
F: 3-PJN,JUN; 2-PPN,JPN,EPN.
Sp: Appears to require the presence of pinyon and juniper for nesting but utilizes jeffrey pines as well as pinyons for food during the winter. Almost always encountered in flocks, often of large size. Notably unpredictable as to numbers and location.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: Although no BBS data exist for this species, I believe that they may be decreasing on the east slope of the Sierra, perhaps due to the poor pinyon nut crops that, I believe, have characterized the recent drought years.
CLARK'S NUTCRACKER - Nucifraga columbiana
Stat: R-SDM West: cS,ifT,ifW. East: cS,icT,icW.
Dist: T West: N:8-11; T:4-12; W:8-10. East: N:7-11; T:B-12; W:7-10.
Sign: WMT-6. Nutcrackers are very common in the Sierra, especially along the east slope, and the Sierra represents an important part of their overall range and an extremely important part of their range in California.
Hab: R: 3-(DFR),(JPN),(RFR),LPN,SCN,EPN,PJN; 2-JUN.
F: 3-(DFR),(JPN),(RFR),LPN,SCN,EPN,PJN; 2-JUN.
Sp: Intimately dependent upon subalpine pine crops (whitebark, foxtail, and limber), which they store in a very complex manner, for feeding themselves and their nestlings. Nutcrackers, in fact, are responsible for planting many of the groves of whitebark pines at high elevations (Tomback 1982). In winter utilizes pinyon and jeffrey pines crops as well. Also utilizes centers of human activity at high elevations for foraging. Nest extremely early in the year.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: An increased response by this species to human activities along roads and ski resorts may be driving up their overall numbers in the Sierra. However a decrease in numbers has occurred in the subalpine Hall Natural Area in very recent years(DeSante pers. observ.), perhaps due to decreased whitebark and pinyon pine crops that may be due to recent drought conditions. Otherwise, I can identify no risks that this species might face.
BLACK-BILLED MAGPIE - Pica pica
Stat: R West: rT. East: uR.
Dist: NC West: T:4-10. East: N:B-7; W:B-7.
Sign: WEST-4. Ssp. hudsonia - WEST-4. This species is far more common in the Great Basin valleys and flats east of the eastern base of the Sierran escarpment than in the Sierra proper. Thus the Sierra is of less importance to the species than for many other WEST-4 species.
Hab: R: 3-JUN,MRI.
F: 3-JUN,WTM,MRI,PAS.
Sp: Nests most commonly near streams, springs, and other sources of water, perhaps because their nest are usually held together to some extent by mud. Commonly nests around ranches. Ranges over many of the Great Basin habitats, but always those that are generally quite open.
Abundance: BBS: 2 routes; 0.26 birds/route. MAPS:
Trends: BBS: UN; -9.8% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Continued persecution by eastside ranchers may be a risk that may be counter-balanced by increased adaptation to human activities. Although BBS data are too limited to identify trends, I believe that the species may have declined recently east of the Sierra.
AMERICAN CROW - Corvus brachyrhynchos
Stat: R-SDM West: rS?,rT. East: rT.
Dist: T West: N:F-2?; T:F-9. East: T:B-8.
Sign: CONT-1. Ssp. hesperis - WEST-4. A species of the Central Valley, American Crows may not nest in the Sierra proper, although there are summer records. Thus, the Sierra is of negligible importance to this species' overall population.
Hab: R: 3-RSP.
F: 3-PAS,RSP.
Sp: Prefers valleys, riparian areas, meadows, and agricultural and residential land.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: I can think of no major risk faced by this species except to suggest that the greatly increased raven population may negatively affect it.
Stat: R West: lfR,rT. East: fR,rT.
Dist: T West: N:F-9; T:F-12; W:F-9. East: N:B-9; T:B-12; W:B-9.
Sign: CAN/WMT-3. Ssp. sinuatus - WEST-4. Because of its rather local Distribution on the West slope, the Sierra is not as important to this species overall range as for other CAN/WMT-3 species.
Hab: R: 3-MHW,MHC,PPN,DFR,MCN,JPN,RFR,LPN,(SCN),ASP,EPN,PJN,JUN,MRI,MCP,BAR.
F: 3-MHW,MHC,PPN,DFR,MCN,EPN,WTM,MRI,PAS; 2-JPN,RFR,ASP,MCP,BAR.
Sp: Widespread east of the Sierran crest, but of local occurrence west of the crest where it is usually associated with roads or areas of human habitation and activity.
Abundance: BBS: 11 routes; 0.79 birds/route. MAPS:
Trends: BBS: IT; 6.4% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: The increase of this species is entirely due its association with roads throughout the Sierra where it forages on the ever increasing roadkills associated with the ever-increasing amount of human vehicle traffic. The bird has also responded to the increased human activity in winter around ski resorts and other winter snow-play areas. The actual increase may be less than suggested by roadside BBS data as the birds are still primarily limited to roadsides in the Sierra.
HORNED LARK - Eremophila alpestris
Stat: SDM West: lfS,rT,icW. East: rS,rT,rW.
Dist: T West: N:F-11; T:F-12; W:F-5. East: N:B-12; T:B-12; W:B-7.
Sign: CONT-1. Distribution in the Sierra not clear. A population of unknown race bred, at least for several years during the late 70s and early 80s, on the West slope of the crest near Mt. Conesss in the central Sierra (DeSante pers. obs.). These birds were presumably of the race lamprochroma. The race sierrae breeds in the northern Sierra from the vicinity of Pittville, in Fall River Valley, to the Truckee Valley. Otherwise the species breeds primarily West of the lower foothills (race rubea in the north and actia in the central and south) and East of the East base of the escarpment (race lamprochroma in the north and central and race ammophila in the south).
Ssp. sierrae - SIE-12; rubea - PCAL-11; actia - PCAL-11; ammophila - PCAL-11; lamprochroma -
RM/GB-8. Sierran populations of these races, except for sierrae, which is endemic to the Sierra, are very small. Thus, the Sierra is of limited importance to them despite the fact that several are classified as PCAL-11. The Sierra is of complete importance, of course, to the race sierrae. More information on the status of sierrae and subspecific identification of the Mt. Conness population is needed.
Hab: R: 2-ADS.
F: 3-WTM,BAR,PAS.
Sp: Requires sparsely-vegetated, short-grass grasslands, heavily-grazed pastures, or dry meadows.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: The alpine Mt. Conness breeding population disappeared after the El Nino winters of 1982 and 1983 and, to my knowledge, never returned. What race were those birds? Why did they breed up there? Have they bred elsewhere in the alpine Sierra? And do they still breed up there? The loss of breeding habitat to extensive agriculture and pesticide contamination are risks that Central Valley/West slope populations face, especially the race actia. The sierrae race should be monitored closely as it is a Sierran endemic. In my experience, however, it seems to be abundant and secure, at least in Sierra Valley.
Stat: NTM West: lrS,xT. East: xT.
Dist: T West: N:F-4?; T:F-5. East: T:7.
Sign: CONT-1. Ssp. subis -CONT-1. This species is mostly absent from the Rocky Mts. and western Great Plains so distribution is really a composite of CAN/EUS-3 and PAC-7. Purple Martins are rare, local nesters on the West slope of the Sierra and their Sierran range is of very little importance to the overall species' range. However, Purple Martins are generally uncommon and very local throughout California so all breeding locations, even those few in the Sierra, are of considerable importance to the species' California range.
Hab: R: 3-MRI,RSP; 2-[MHW],[MHC],[DFR],[PPN],[MCN].
F: 3-WTM,MRI,PAS,RSP.
Sp: Nests in small colonies in large snags where there are multiple natural cavities or cavities made by the larger woodpeckers such as Acorn and Lewis' Woodpeckers and flickers. Usually forages high in the air.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: Although BBS trend data do not exist for this species, it is likely decreasing in the Sierra. This is especially significant as populations appeared to be increasing formerly (Grinnell and Miller 1944). Usurpation of nest sites by European Starlings may be a major factor. Loss of snags, especially large snags with multiple woodpecker holes, is a risk. Possible declines in Lewis' and Acorn Woodpeckers is another potential risk. Use of pesticides is another potential risk. High mortality on South American wintering grounds (due to massive pesticide use) is a likely factor that has been documented for eastern populations at least.
TREE SWALLOW - Tachycineta bicolor
Stat: NTM West: uS. East: uS,xT.
Dist: T West: N:F-9. East: N:B-8; T:B-10.
Sign: CONT-1. Rather uncommon in the Sierra, so Sierran range a little less important to the species than for some other CONT-1 species.
Hab: R: 3-MRI,RSP; 2-MHW,MHC,PPN,LPN,EPN.
F: 3-WTM,MRI,PAS,RSP; 2-MHW,MHC,PPN,LPN,EPN,MCP.
Sp: Generally requires the presence of water or moist habitat in its cruising range. Usually forages at low or moderate heights. Cavity nester that responds well to bird boxes.
Abundance: BBS: 12 routes; 1.44 birds/route. MAPS:
Trends: BBS: LI; 6.1% per year **
Demographics: MAPS:
Potential risks and suggested causes of population trends: I have no explanation for this species' increase except to note that it continues to adapt well to human presence. Loss of riparian habitat, loss of snags, usurpation of nests by starlings, and pesticide use are all risks that seem to be outweighed by whatever is causing the increase.
VIOLET-GREEN SWALLOW - Tachycineta thalassina
Stat: NTM West: cS,rT. East: cS.
Dist: T West: N:F-9; T:F-10. East: N:6-10.
Sign: WEST-4. Ssp. lepida - WEST-4.
Hab: R: 3-MHW,MHC,PPN,MCN,MRI,RSP.
F: 3-MHW,MHC,PPN,MCN,WTM,MRI,BAR,PAS,RSP; 2-DFR,JPN,EPN.
Sp: Nests both in tree cavities and in crevices and crannies of cliff faces; thus, common in both rather heavily forested and unforested terrain. Generally does not require the presence of water in its cruising range. Generally forages at greater heights than Tree Swallow. Readily accepts crannies in human-made structures and bird boxes.
Abundance: BBS: 9 routes; 1.30 birds/route. MAPS:
Trends: BBS: DT; -9.4% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: It is possible that the decreasing tendency in this species is related to increases in Tree Swallows. However, I think of Violet-greens as being generally much more abundant and widespread in the Sierra than Tree Swallows despite the similarities in BBS abundance indices. Loss of snags and pesticide use are potential risks. Unlike Tree Swallows, Violet-greens usually forage high like swifts, which are also decreasing. Perhaps pesticide use has lessened the number of up-mountain wind-drifted insects.
NORTHERN ROUGH-WINGED SWALLOW - Stelgidopteryx serripennis
Stat: NTM West: uS,xT. East: rS,rT.
Dist: T West: N:F-5; T:F-9. East: N:B-7; T:B-10.
Sign: US-2. Ssp. serripennis - US-2 (except SW). Because this species is uncommon in the Sierra, its importance there is less than for some other US-2 species.
Hab: R: 3-MHW,MHC,PPN,(EPN),(PJN),(JUN),MRI,MCP,BAR,RSP.
F: 3-MHW,MHC,PPN,(EPN),(PJN),(JUN),WTM,MRI,PAS,RSP; 2-MCP.
Sp: Nest in natural or rodent-excavated holes in the earthen banks of streams, washes, and gullies. Probably because of its nesting requirements, usually found along streams, but also occurs in the absence of water if suitable nesting banks exist. Generally forages low over the ground or water.
Abundance: BBS: 7 routes; 0.81 birds/route. MAPS:
Trends: BBS: UN; -2.6% per year **
Demographics: MAPS:
Potential risks and suggested causes of population trends: Because, this species’ nesting habits are similar to those of the kingfisher, which is declining, loss of nesting habitat may be a risk. Pesticide use is another possible risk.
CLIFF SWALLOW - Hirundo pyrrhonota
Stat: NTM West: lcS,xT. East: lfS,rT.
Dist: T West: N:F-5; T:F-9. East: N:B-7; T:B-12.
Sign: CONT-1. Ssp. pyrrhonota - Distribution complex, essentially eastern North America and Pacific states, most closely approximated by US-2. This is the breeding race on the west slope and the northern part of the east slope; hypopolia - essentially WEST-4, although absent form the Pacific region and the Southwest. This is the breeding form on the central and southern East slope. Actual breeding locations on the east slope are few; the species becomes much more common east of the eastern base of the Sierran escarpment. Similarly, on the west slope, the species is much more abundant in the lower foothills than higher in the Sierra proper.
Hab: R: 3-(PPN),MRI,RSP.
F: 3-(PPN),WTM,MRI,PAS,RSP.
Sp: Nests in large colonies that plaster their mud nests on natural cliff faces and, more commonly, under the eaves of human-made structures. Presence of mud for nest-building is an important requisite; thus, they usually occur near some source of water. Generally forages rather high in the air.
Abundance: BBS: 9 routes; 12.60 birds/route. MAPS:
Trends: BBS: IT; 1.1% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: The increase in Cliff Swallows in the Sierra is entirely a result of their adaptation to human-made buildings and bridges and to the increase in new concrete bridges that are very much to their liking. In recent times, Cliff Swallows have colonized the Central Valley (where there are no cliffs) primarily by nesting under bridges, especially those crossing irrigation aquaducts. They have followed and are still following such bridges (and other structures) ever higher up the west slope of the Sierra. Gaines (1988) also noted that they exploded in numbers on the east slope and east of the Sierran escarpment between 1982 and 1987. Pesticide use and perhaps a reduction in up-slope wind-drifted insects are the only likely risks.
BARN SWALLOW - Hirundo rustica
Stat: NTM West: fS,xT. East: rS?,rT.
Dist: T West: N:F-5; T:F-9. East: N:B-7?; T:B-7.
Sign: CONT-1. Ssp. erythrogaster - CONT-1. I know of no actual nesting record on the east slope of the Sierra proper; the species becomes fairly common in the valleys and basins east of the eastern base of the escarpment. Because this species is less common in the Sierra than elsewhere, its Sierran range is of less importance overall than that of some other CONT-1 species.
Hab: R: 3-MHW,MHC,PPN,DFR,MCN,PJN,WTM,MRI,MCP,[RSP].
F: 3-PPN,WTM,PAS,RSP; 2-MRI.
Sp: Nests almost exclusively under or inside human-made structures. Requires mud for nests and, usually, water or moist habitat over which it forages close to the ground.
Abundance: BBS: 9 routes; 1.84 birds/route. MAPS:
Trends: BBS: PS; -0.5% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: This low-foraging species is possibly stable in the Sierra. As it adapts well to human presence and is very much dependent on human structures for nesting, its apparent stability may reflect a balance between increased nesting habitat and decreased prey availability due to pesticide use. This species certainly has increased greatly in the Sierra, both in aggregate numbers and in widespread nature of its distribution, in historical times. Gaines (1988), for example, noted that Barn Swallows were unknown in Yosemite National Park before 1949.
MOUNTAIN CHICKADEE - Parus gambeli
Stat: R West: cS,icW. East: cR.
Dist: T West: N:3-10; W:F-10. East: N:B-10; W:B-10.
Sign: WMT-6. Ssp. abbreviatus - PAC-7.
Hab: R: 3-PPN,MCN,JPN,RFR,LPN,EPN,RSP; 2-MHC,DFR,SCN,ASP,PJN,JUN,MRI.
F: 3-MHC,PPN,MCN,JPN,RFR,LPN,EPN,RSP; 2-DFR,SCN,ASP,PJN,JUN,MRI.
Sp: Found in all conifers except digger pines on the west slope; somewhat less common in pinyon and juniper on the east slope. Cavity nester.
Abundance: BBS: 16 routes; 28.64 birds/route. MAPS: 3.02 ad/600 nh
Trends: BBS: DD; -1.9% per year **
Demographics: MAPS: Prod. index: 47.7% yg.
Potential risks and suggested causes of population trends: The definitely decreasing trend for this species in the Sierra is hard to explain. Loss of snags could be a potential risk, but the species readily nests in small cracks and crevices in living trees. I would expect this species to be just about the most stable of Sierran landbirds. If this decline is real, it may signify a general deterioration of the Sierran environment. I would expect that it would take extensive clearcutting, general deterioration of the prey base, or major climate change to seriously affect this species, but it may be more responsive to relatively minor environmental changes than I believe. The population and demographic trends of this species should be monitored as a standard for resident species. Despite some annual fluctuations, which seem to be less severe than for more highly migratory species, Mountain Chickadees have remained relatively stable over 22 years in the subalpine Hall Natural Area (DeSante pers.observ.).
CHESTNUT-BACKED CHICKADEE - Parus rufescens
Stat: R West: luR. East:
Dist: NC West: N:3-5; W:3-5. East:
Sign: PAC-7. Ssp. rufescens - PAC-7. A recent immigrant to the west slope of the Sierra, where it is of local, uncommon occurrence. Thus, the Sierra is of very little importance to this species' total population.
Hab: R: 3-DFR,RSP; 2-MRI.
F: 3-DFR,RSP; 2-MHW,MHC,PPN,MRI.
Sp: Requires rather moist, dense forest, especially of Douglas firs mixed with maples, alders, and madrones, but occurs less commonly in black oaks and mixed coniferous forest. Cavity nester.
Abundance: BBS: 2 routes; 0.15 birds/route. MAPS: 0.04 ad/600 nh
Trends: BBS: UN; -12.5% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Except for a single specimen collected at 3,000' elevation in the Feather River Canyon in 1939, this species was unknown in the Sierra until 1951 and in the Yosemite region until 1958. It appears, therefore, to have only recently colonized the Sierra from the north. Although this species now shows a very pronounced decrease on the two BBS routes where it occurred, it is hard to know whether or not this represents a regional decline. Other than loss of snags and general loss of habitat to logging operations, it is hard to identify risks. The recent decline in this humid-forest-loving species, if it is real, may be due to the generally dry conditions in the Sierra in recent years.
OAK TITMOUSE - Baeolophus inornatus
Stat: R West: fS,xT,ifW. East: lrP.
Dist: TW,SE West: N:F-3; T:F-8; W:F-4. East: N:B-8; W:B-8.
Sig: PCAL-11 (although the species extends into extreme southern Oregon). Ssp. inornatus west slope, except for extreme southern part - PCAL-11. Only at low elevations on the west slope is this species fairly common in the Sierra, so the Sierra is less important to this race than to many other PCAL-11 races; kernensis extreme southern end of the Sierra on both the west and east slopes - SIE-12. Although found only at lower elevations in the Sierra, this race is effectively limited to the foothills of the Sierra.
Hab: R: 3-MHW,MHC,RSP; 2-PPN.
F: 3-MHW,MHC,PPN,RSP.
Sp: Prefers oaks, especially blue oaks, and digger pines and favors open woodlands. Like Nuttall's Woodpecker, some birds apparently winter at higher elevations than the breeding range. Cavity nester.
Abundance: BBS: 3 routes; 0.17 birds/route. MAPS:
Trends: BBS: UN; -9.4% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Here is another oak-woodland species that may be decreasing. Although acorns are not a staple of its diet, its dependence on oak woodlands is very high; if oak woodlands in general, and large old oaks with abundant cavities in particular, are declining, the species will be adversely affected. As with virtually all insectivores, pesticides present a risk.
JUNIPER TITMOUSE - Baeolophus griseus
Stat: R West: East: lrS,rW.
Dist: CE West: East: N:B-8; W:B-8.
Sign: RM/GB-8. Occurs only as far north as southern Oregon, southern Idaho, and southern Wyoming; thus, almost SW-9. Ssp. zaleptes locally, central and, possibly, northern portions of east slope, but apparently does not breed in the Sierra proper and is only a rare winter resident in the central and, possibly, northern portion - PCAL-11 (although this race also extends into southern Oregon and western Nevada). Because of this species’ marginal occurrence in the Sierra, the Sierra is less important to it than to many other PCAL-11 species.
Hab: R: 3- PJN,JUN.
F: 3- PJN,JUN.
Sp: Prefers pinyons and junipers and favors open woodlands. Like Oak Titmouse, this species wanders into atypical habitats during fall and winter when they stray into cottonwood groves, willow and buffalo-berry thickets, and even treeless sagebrush scrub. Cavity nester.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: Because of this species’ limited occurrence in the Sierra, very little is known about potential risks.
BUSHTIT - Psaltriparus minimus
Stat: R West: cR,rT. East: rS,rT,uW.
Dist: T West: N:F-4; T:F-10; W:F-4. East: N:B-8; T:B-10; W:B-8.
Sign: WUS-5. Ssp. californicus west slope and extreme northerly portion of east slope - PCAL-11 (although this race also extends to extreme southern Oregon); plumbeus east slope except extreme northerly portion - RM/GB-8. (Grinnell and Miller [1944] limited plumbea to the northern portion of the east slope and recognized providentialis on the central and southern portions of east slope, but providentialis was not recognized by AOU [1957]. If providentialis is recognized, it becomes PCAL-11 and plumbea remains RM/GB-8.) Regardless, because the center of abundance for Bushtits lies east and west of the Sierra proper, the Sierra is less important to the overall and California populations of these races than the PCAL-11 and RM/GB-8 classifications suggest.
Hab: R: 3-RSP; 2-MHW,MHC,PJN,JUN,MRI,[MCP].
F: 3-RSP; 2-MHW,MHC,PJN,JUN,MRI,[MCP].
Sp: Seems to require large shrubs and small trees for foraging and nesting. On the west slope prefers chaparral, open oak woodland, and riparian, while on the east slope prefers pinyons, junipers, and riparian habitats.
Abundance: BBS: 11 routes; 1.20 birds/route. MAPS:
Trends: BBS: DT; -7.7% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: This species is most abundant in relatively dry foothill situations, is a year-round resident, and is not dependent upon cavities; its decreasing tendency is therefore surprising. Nest predation by Scrub Jays may be a major risk, though Scrub Jays may be declining. Pesticides are the only other risk I can suggest.
RED-BREASTED NUTHATCH - Sitta canadensis
Stat: R-SDM West: cS,ifT,icW. East: ifS,ifT,ifW.
Dist: T West: N:3-8; T:F-10; W:F-10. East: N:7-8; T:B-10; W:B-10.
Sign: CAN/WMT-3. Populations of this species are typically very high in the Sierra, so that the Sierra may be more important to this species than suggested by CAN/WMT-3. Hab: R: 3-PPN,DFR,MCN,JPN,RFR; 2-LPN,EPN. F: 3-PPN,DFR,MCN,JPN,RFR; 2-MHC,LPN,EPN,RSP.
Sp: Prefers dense, shady, mature forests at mid-elevations. Cavity nester, but often digs its own nesting cavity in the manner of a woodpecker.
Abundance: BBS: 17 routes; 17.78 birds/route. MAPS: 0.77 ad/600 nh
Trends: BBS: LS; -0.8% per year *
Demographics: MAPS: Prod. index: 66.9% yg.
Potential risks and suggested causes of population trends: The overall population trend for this highly irruptive species is likely relatively stable (only a slight decreasing trend was noted on BBS routes). Loss of snags is a risk as are logging operations since the species prefers dense, shady, mature mid-elevation forests. The fact that the species is not very dependent on acorn or pine nut crops is probably the reason that it is not declining the way White-breasted Nuthatches appear to be. Pesticide use on forest insect outbreaks could also be a major risk.
WHITE-BREASTED NUTHATCH - Sitta carolinensis
Stat: R West: lfR. East: fR.
Dist: T West: N:F-10; W:F-10. East: N:B-10; W:B-10.
Sign: CONT-1. Ssp. aculeata western foothills upslope probably to ponderosa pine zone - PAC-7; tenuissima east slope and higher part of west slope downslope probably through lodgepole pine zone - RM/GB-8 (but generally confined to the Great Basin). Racial identity of mid-elevation nuthatches, where they are often absent or rare, is uncertain; more study is needed here. Because the center of abundance for aculeata lies in the foothill belt, the Sierra proper may be less important for this race than other PAC-7 species or races.
Hab: R: 3-MHW,MHC,PPN,(DFR),(MCN),JPN,LPN,EPN,PJN,JUN,MRI,RSP; 2-(RFR),SCN.
F: 3-MHW,MHC,PPN,(DFR),(MCN),JPN,LPN,EPN,PJN,JUN,MRI,RSP; 2-(RFR),SCN.
Sp: Prefers open forest and woodland, especially partial to oaks (particularly blue and valley oaks) and digger pines in the foothill, to jeffrey and lodgepole pines at higher elevations, and to jeffrey and large pinyons on the east slope. Cavity nester that does not dig its own holes.
Abundance: BBS: 14 routes; 2.04 birds/route. MAPS: 0.04 ad/600 nh
Trends: BBS: PD; -5.3% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: The subspecies of the western foothills, aculeata, is highly dependent on acorn crops in winter, while the high-elevation and east slope subspecies, tenuissima, is to some extent dependent on pine nut crops in winter. The possible decreasing trend of the species may well be caused by problems with acorn production and/or loss of oak woodland as has been suggested above for Band- tailed Pigeon, Acorn Woodpecker, Scrub Jay, and, perhaps, even Oak Titmouse. Loss of snags, especially large old oaks, may also be a risk for this cavity nester.
PYGMY NUTHATCH - Sitta pygmaea
Stat: R West: luR,rT. East: fR,rT.
Dist: T West: N:3-7; T:3-10; W:3-7. East: N:B-8; T:B-10; W:B-8.
Sign: WMT-6. Ssp. melanotis - WMT-6.
Hab: R: 3-PPN,MCN,JPN,EPN,RSP; 2-MRI.
F: 3-PPN,MCN,JPN,EPN,RSP; 2-MRI.
Sp: Prefers ponderosa and, to a lesser extent, jeffrey pines on the west slope and jeffry pines on the east slope. Cavity nester that often digs its own nest hole. Communal rooster.
Abundance: BBS: 4 routes; 0.32 birds/route. MAPS:
Trends: BBS: UN; 0.4% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: This cavity- nesting "yellow pine" specialist prefers jeffrey pines on both slopes and ponderosa pines on the west slope. Because it avoids oak woodlands and prefers open forest of rather widely spaced trees, it faces fewer risks from logging and habitat loss and degradation than other nuthatches, especially White-breasted. It is, therefore, not surprising that it seems to enjoying a stable tendency. Loss of snags may be a risk, especially, because it is a communal rooster, preferring large snags with multiple cavities.
BROWN CREEPER - Certhia americana
Stat: R-SDM West: fS,ifW. East: fS,iuW.
Dist: T West: N:3-10; W:F-8. East: N:B-10; W:B-8.
Sign: CAN/WMT-3. Ssp. zelotes - CAL-10. Populations are generally high in the Sierra which may be even more important to this race than CAL-10.
Hab: R: 3-MHC,PPN,DFR,MCN,JPN,RFR,EPN,MRI,RSP; 2-[LPN].
F: 3-MHC,PPN,DFR,MCN,JPN,RFR,EPN,MRI,RSP; 2-MHW,[LPN].
Sp: Prefers dense, shady groves of mature forest. Nests behind pieces of loosened bark generally on large living or dead trees.
Abundance: BBS: 17 routes; 4.35 birds/route. MAPS: 1.75 ad/600 nh
Trends: BBS: PD; -3.5% per year
Demographics: MAPS: Prod. index: 64.3% yg.
Potential risks and suggested causes of population trends: Because this species prefers dense, shady mature forest, logging operations of most kinds are a risk. Also, because it nests behind loose bark of large dead or living trees, loss of snags could also be a risk. Loss of oaks, however, is not a major risk as it does not generally prefer oak woodland or oak forest. Pesticide use on forest insect outbreaks could be an important risk.
ROCK WREN - Salpinctes obsoletus
Stat: SDM West: luS,luW. East: uS.
Dist: T West: N:F-12; W:F-3. East: N:B-12.
Sign: WEST-4. Ssp. obsoletus - WEST-4. Occurs most commonly at lower elevations on both slopes and along the crest of the Sierra at or above treeline. The Sierra represents an important portion of their breeding range in California and overall.
Hab: R: 3-MHW,MHC,JUN,MCP,BAR.
F: 3-BAR; 2-MCP.
Sp: Prefers rock outcroppings, rock slide, talus slopes, and fractured cliff faces.
Abundance: BBS: 4 routes; 0.19 birds/route. MAPS:
Trends: BBS: UN; 0.1% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Because of the rugged, rocky habitat that it prefers, this species probably faces relatively slight risks from development pressures in the foothills, and very little or no risk from forestry practices.
CANYON WREN - Catherpes mexicanus
Stat: R West: fR,xT. East: uR,xT.
Dist: T West: N:F-6; T:F-10; W:F-6. East: N:B-8; T:B-10; T:B-8.
Sign: WUS-5. Ssp. conspersus - WUS-5. The Sierra represents a very important portion of their breeding range in California and overall.
Hab: R: 3-MRI,BAR.
F: 3-MRI,BAR.
Sp: Prefers steep canyon walls and boulder fields in steep rocky stream canyons. More shade-tolerant and water-loving than Rock Wren.
Abundance: BBS: 3 routes; 0.15 birds/route. MAPS:
Trends: BBS: UN; 1.7% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Like Rock Wren, this species habitat preferences make it subject to relatively little risk from development and forestry pressures. Climatic trends toward decreasing moisture regimes could be a risk, as could increased disturbance by rock climbers.
BEWICK'S WREN - Thryomanes bewickii
Stat: R West: fR,rT. East: rS,uW.
Dist: T West: N:F-3; T:F-5; W:F-3. East: N:B-7; W:B-7.
Sign: US-2. Confined, however, to the southern half of the U.S. and almost extirpated in the East, so species' significance classification is more properly WUS-5. Ssp. drymoecus northern and central portions of the west slope - PCAL-11; correctus southern portion of the west slope and extreme southern portion of east slope - PCAL-11; atrestus northern portion of east slope although may not breed in the Sierra proper - PCAL11 (although extends into central southern Oregon and northwestern Nevada); eremophilus central and southern east slope (except extreme southern part) - RM/GB-8. The metropolis of the ranges of all of these subspecies does not include the Sierra proper, so the Sierra is of somewhat less importance than these classifications suggest.
Hab: R: 3-PJN,JUN,MRI,MCP,RSP.
F: 3-PJN,JUN,MRI,MCP,RSP.
Sp: Prefers shrubland and brushy riparian at lower elevations on both slopes. Not attracted to human habitations as much as House Wren. Crevice or sometimes cavity nester.
Abundance: BBS: 11 routes; 0.58 birds/route. MAPS:
Trends: BBS: DT; -8.6% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Development pressures in the Sierra foothills could be risk as could catastrophic fires caused by years of fire suppression. Loss of foothill riparian habitat is another possible risk. Although a cavity nester, loss of snags may not be much of a problem as it will utilize an amazing variety of nooks and crannies. Fortunately for the species as a whole, western North American populations seem to be able to adapt well to the presence of human activities and encroachment and, in general, are persisting well. Populations of eastern North America, however, are very nearly extirpated.
HOUSE WREN - Troglodytes aedon
Stat: SD-NTM West: fS,fT. East: cS,fT.
Dist: T West: N:F-5; T:F-10. East: N:B-8; T:B-10.
Sign: CONT-1. Ssp. parkmanii - WEST-4. The Sierra does not constitute the metropolis of this subspecies range in California so it may be of somewhat less importance than WEST-4. Hab: R: 3-MRI,RSP; 2-MHW,MHC,[ASP]. F: 3-WTM,MRI,RSP, 2-MHW,MHC,MCP,[ASP].
Sp: Prefers riparian and other moist hardwood habitats. Crevice or cavity nester that occurs often in association with human habitations.
Abundance: BBS: 11 routes; 1.95 birds/route. MAPS: 0.39 ad/600 nh
Trends: BBS: PS; -0.8% per year
Demographics: MAPS: Prod. index: 66.5% yg.
Potential risks and suggested causes of population trends: The stability in this species' population trend may be due to its adaptability to human habitations. Risks include loss of riparian and, to a lesser extent, oak woodland habitat. Loss of snags may also be a risk, but, like Bewick's Wren, although perhaps to a lesser degree, the species can use a variety of cracks and crannies.
WINTER WREN - Troglodytes troglodytes
Stat: R-SDM West: luS,rT,luW. East: rT,rW.
Dist: T West: N:3-6; T:F-8; W:F-5. East: T:7-10; W:6-8.
Sign: CAN/WMT-3. Absent, however, from the Rocky Mountains. Ssp. pacificus - PAC-7. Generally uncommon or rare in the Sierra which is not an extremely important portion of this species' range even in California.
Hab: R: 3-MHC,[DFR],MCN,MRI,RSP; 2-(PPN),(JPN).
F: 3-MHW,MHC,PPN,DFR,MCN,JPN,RFR,LPN,SCN,ASP,EPN,PJN,JUN,MRI,MCP,RSP.
Sp: Prefers the moist shady interior of dense old-growth forests, especially along streams.
Abundance: BBS: 7 routes; 0.36 birds/route. MAPS: 0.08 ad/600 nh
Trends: BBS: PD; -5.0% per year **
Demographics: MAPS: Prod. index: 71.5% yg.
Potential risks and suggested causes of population trends: The most important risk is the loss of dense, shady, old-growth forest upon which this species is dependent. Although found on only seven BBS routes, the significant negative BBS trend of this species, may signal real trouble for this species.
MARSH WREN - Cistothorus palustris
Stat: SDM West: lrS,rT. East: rT.
Dist: T West: N:5; T:F-9. East: T:B-10.
Sign: CONT-1. Ssp. plesius - RM/GB-8. In the Sierra proper, apparently breed only in marshes at Lake Tahoe; however, also breeds fairly commonly in marshes near Mono Lake and probably elsewhere east of the east base of the Sierran escarpment. In any case, the Sierra does not constitute an important portion of the range of the species overall or in California.
Hab: R:
F:
Sp: Confined for breeding to fresh water marshes containing a dense growth of tall cattails or tules.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: Drainage and destruction of marshes are a major risk for this species. Use of pesticides for mosquito abatement could be another risk. There probably exist no Sierran trend data for this species but I suspect that its continued existence at Lake Tahoe could be under considerable risk. The Lake Tahoe population needs to be monitored.
AMERICAN DIPPER - Cinclus mexicanus
Stat: R-SDM West: fS,uT,fW East: fR,uT.
Dist: T West: N:2-10; T:F-12; W:F-8. East: N:B-10; T:B-12; W:B-10.
Sign: WMT-6. Ssp. unicolor - WMT-6. The Sierra represents an extremely important portion of this species range, particularly in California.
Hab: R: 3-MRI,BAR,RSP.
F: 3-BAR,RSP; 2-MRI.
Sp: Confined to generally fast-moving streams, rivers, and glacial lakes throughout the Sierra. Nests on rock ledges just above flowing water or behind waterfalls; occasionally nests under bridges. Abundance: BBS: 7 routes; 0.30 birds/route. MAPS:
Trends: BBS: ST; -0.5% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: In general, this species seems fairly immune to most risks faced by other Sierran species. Thus, the fact that it seems to show a stable tendency is not unexpected. Loss of habitat due to damming of rivers is a threat, and nest failure due to rapid and unpredictable changes in stream flows resulting from releases of water from dams is another risk.
GOLDEN-CROWNED KINGLET - Regulus satrapa
Stat: R-SDM West: cS,ifW. East: uS,iuW.
Dist: T West: N:4-10; W:F-8. East: N:7-10; W:B-8.
Sign: CAN-WMT-3. Ssp. amoenus - WMT-6. Grinnell and Miller (1944) did not recognize amoenus as distinct from olivaceus which, as presently defined, is confined to the coastal regions of southeastern Alaska, British Columbia, Washington, and Oregon; they considered Sierran birds to be olivaceus. This species is very common in the Sierra which, therefore, may be of more importance to the subspecies amoenus than expected from its WMT-6 importance classification.
Hab: R: 3-MHC,PPN,DFR,MCN,RFR,LPN,(SCN); 2-JPN,EPN.
F: 3-MHC,PPN,DFR,MCN,RFR,LPN,(SCN); 2-JPN,EPN,MRI,[RSP].
Sp: Prefers mature, well-shaded forests, particularly old-growth red firs, but also dense stands of mature Douglas firs and mixed conifers. Generally forages quite high in the canopy.
Abundance: BBS: 17 routes; 7.03 birds/route. MAPS: 1.18 ad/600 nh
Trends: BBS: LD; -4.0% per year *
Demographics: MAPS: Prod. index: 73.6% yg.
Potential risks and suggested causes of population trends: This species is likely decreasing in the Sierra at the relatively substantial rate of –4.0% per year. Risks include logging practices that eliminate old growth and mature forests and that tend to open up dense forests of all ages. Thus, forestry practices may be responsible for the rather substantial likely decrease in this species. It is possible that very hard winters (such as the El Nino winters of 1982 and 1983) could cause massive mortality in this smallest of resident Sierran species and that recovery to "normal" higher population levels could take a long time. I would doubt such a scenario, however, because the species demonstrated both a high MAPS productivity index and a high number of young fledged per territory in the subalpine zone (DeSante 1990).
RUBY-CROWNED KINGLET - Regulus calendula
Stat: SDM West: uS,fT,fW. East: rS,fT,rW.
Dist: T West: N:7-10; T:F-10; W:F-4. East: N:8-10; T:B-10; W:B-7.
Sign: CAN-WMT-3. Ssp. cineraceus - WMT-6. This species, in contrast to the Golden-crowned Kinglet, is probably relatively less numerous in the Sierra than in most other mountains in its range; thus, the Sierra may be less important to cineraceus than expected from its WMT-6 importance classification.
Hab: R: 3-(PPN),(MCN),RFR,LPN,SCN; 2-(DFR),JPN,EPN.
F: 3-MHW,MCN,PPN,MCN,RFR,LPN,SCN,MCP,RSP; 2-DFR,JPN,EPN,PJN,(MRI).
Sp: Strongly prefers lodgepole pine and mountain hemlock forests whereit favors rather open forest and the edges of meadows. Like Golden-crowns, Ruby-crowns typically forage high in the canopy during thebreeding season.
Abundance: BBS: 8 routes;0. 67 birds/route. MAPS: 0. 03 ad/600 nh
Trends: BBS: DT; -6. 1% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Because they prefer more open forest at higher elevations than Golden-crowns, Ruby-crowns may suffer less risk from logging practices than Golden-crowns. My personal feeling in the central Sierra, however, is that Ruby-crowns may have decreased substantially over the past 30 years, and this is substantiated bytheir -6. 1% per year decreasing tendency from BBS data.
BLUE-GRAY GNATCATCHER - Polioptila caerulea
Stat: SD-NTMWest: uS,rT. East: uS.
Dist: TW,CSEWest: N:F-5; T:F-8. East: N:B-8.
Sign: US-2. Ssp. amoenissima - WUS-5. This subspecies is quite uncommon north of central California, central Nevada, southern Utah, and central Colorado, so actual importance classification is closer to SW-9. The subspecies is, however, quite uncommon in the Sierra which, therefore, is of less importance to it than for some other SW-9 subspecies.
Hab: R: 2-[MHW],PJN,JUN,[MCP].
F: 2-[MHW],PJN,JUN,[MCP].
Sp: Prefers open woodlands with an open shrubby understory. On the westslope prefers oak woodlands but also less commonly inhabits digger,knobcone and ponderosa pines. On the east slope prefers pinyonpines, junipers, and mahoganies.
Abundance: BBS: 2 routes;0. 02 birds/route. MAPS:
Trends: BBS: UN;-23. 5% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: This species has apparently declined considerably during the past 50 years as Grinnell and Miller (1944) considered it common over virtually all of its California range. The cause of this decline is not clear, although cowbird parasitism has been suggested as a probable cause of decline elsewhere in California. Loss of oak woodland habitat may be another risk.
WESTERN BLUEBIRD - Sialia mexicana
Stat: R-SDM West: lfS,rT,iuW. East: luS,xT.
Dist: TW,NE West: N:F-5; T:F-10; W:F-3. East: N:B-8, T:B-8.
Sign: WEST-4. Ssp. occidentalis - WUS-5 but replaced by bairdii over most of the southwestern U. S. Generally, this species is only fairly common in the Sierra; thus, the Sierra may be of less importance to this species than to many other WEST-4 species or WUS-5 subspecies.
Hab: R: 3-MHW,MHC,MRI,RSP; 2-PPN,DFR,MCN,JPN,EPN.
F: 3-MHW,MHC,WTM,MRI,PAS,RSP; 2-PPN,DFR,MCN,JPN,EPN,JUN.
Sp: Prefers open stands of oak or mixed oak-coniferous woodland mixed with open grassy meadows or hillsides. Also occurs, at least in the southern Sierra, in open or even semi-closed ponderosa pine or mixed coniferous forest. Also occurs in open riparian habitat with scattered trees. Requires lookout perches on woodland edges or fence posts and telephone wires from which to forage. Cavity nester, requiring woodpecker-excavated holes or natural cavities in dead wood. Abundance: BBS: 8 routes;0. 30 birds/route. MAPS: 0. 17 ad/600 nh
Trends: BBS: IT;6. 5% per year
Demographics: MAPS: Prod. index: 33. 6% yg.
Potential risks and suggested causes of population trends: Risks include loss of snags, usurpation of nest holes by starlings, and loss of open oak woodlands and riparian areas to residential and other development. May be favored by some kinds of logging operations that open dense lower elevation forests, but tends to avoid areas grown up to dense chaparral or brush; thus, most logging operations may be detrimental to the species. Still, thespecies shows an increasing tendency in the Sierra.
MOUNTAIN BLUEBIRD - Sialia currucoides
Stat: SDM West: uS,rT,rW. East: uS,fT,rW.
Dist: T West: N:8-12; T:F-12; W:F-4. East: N:5-12; T:B-12; W:B-7.
Sign: WMT-6.
Hab: R: 3-(PPN),(MCN),LPN,ASP,EPN,MRI; 2-SCN.
F: 3-(PPN),(MCN),LPN,ASP,EPN,WTM,MRI,PAS; 2-SCN,ADS.
Sp: Requires open country with short grass for foraging and dead trees or snags with cavities for nesting. Thus, occurs most commonly at the edges of large meadows, grasslands, and alpine barrens or fell fields. Responds well to human-made structures for nesting in such habitats.
Abundance: BBS: 6 routes;0. 24 birds/route. MAPS:
Trends: BBS: ST; 0. 0% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Loss of snags is a risk, but, because this species generally occurs at higher elevations than most logging operations are conducted, may not be affected much by forestry practices.
TOWNSEND'S SOLITAIRE - Myadestes townsendi
Stat: SDM West: uS,iuW. East: uS,fW.
Dist: T West: N:5-10; W:F-9. East: N:7-10; W:B-9.
Sign: WMT-6. Ssp. townsendii - WMT-6.
Hab: R: 3-PPN,MCN,JPN; 2-RFR,[LPN],[EPN].
F: 3-MHW,PPN,MCN,JPN,PJN,JUN; 2-RFR,[LPN],[EPN],MRI,[MCP].
Sp: Prefers rather open forests and woodlands with a well developed shrubby understory, most often on ridges or well-drained slopes, but also less frequently on shady flats or in canyonbottoms. Nests on or near the ground under rocks or logs, at the base of a tree, or on cut banks. In winter on the east slope, virtually always associated with juniper berries, its winter mainstay. On the west slope in winter, utilizes other berries, especially mistletoe, toyon, and elderberries.
Abundance: BBS: 15 routes;1. 27 birds/route. MAPS:
Trends: BBS: PD;-2. 9% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Could be affected negatively or positively by logging operations depending on their type and extent. Climate changes that negatively affect berry crops would be major risk. Perhaps the recent tendency toward drought years may be partially responsible for the possible decline. However, at least in the vicinity of Tioga Pass, the species has apparently increased the upper elevational limit of its breeding range in recent years from about 9,000' to above 10,000', presumably in response to drier and more snow-free conditions (DeSante unpub. data).
SWAINSON'S THRUSH - Cartharus ustulatus
Stat: NTM West: rS,xT. East: rS.
Dist: TW,NCEWest: N:F-8; T:F-9. East: N:5-8.
Sign: CAN/WMT-3. Ssp. West slope: ustulatus - PAC-7 (oedicus according to Marshall [1988] - PAC-7); east slope: swainsoni - CAN/WMT- 3 (almae according to Grinnell and Miller [1944] and Marshall [1988] - RM/GB-8). AOU (/1957) did not recognize almae and merged it with swainsoni. Marshall (1988) recoqnized both almae and oedicus. Regardless of details of taxonomy, it is clear that the west slope and east slope Swainson's Thrushes represent different subspecies. Because the Swainson's Thrush has become so rare in the Sierra, its populations there are of little importance to the overall species' population or to the particular subspecific populations. However, it is critical to realize that we may now be witnessing the last days of the Swainson's Thrush in the Sierra.
Hab: R: 3-MRI.
F: 3-MRI; 2-MHW,MHC,DFR,MCN,RFR,EPN,RSP.
Sp: Requires dense, shrubby, understory vegetation on moist forested slopes near streams or the edges of meadows; or dense riparian vegetation along streams or in meadows but always in or on the edgeof a forested situation. The overstory forest is typically mixed hardwood-conifer, Douglas fir, mixed conifer, or red fir.
Abundance: BBS: 5 routes;0. 16 birds/route. MAPS: 0. 43 ad/600 nh
Trends: BBS: DT;-5. 4% per year
Demographics: MAPS: Prod. index: 0. 0% yg.
Potential risks and suggested causes of population trends: The Swainson's Thrush has been declining in the Sierra for at least 50 years. They were formerly recorded as being fairly common breeders in the Sierra at many locations, such as Yosemite Valley (Gaines 1988) and Whitaker's Forest (Marshall 1988), where they no longer occur. Marshall (1988) made a strong case that the cause of this remarkable decline (at least on the west slope) was deforestation on its Neotropical wintering grounds in subtropical and tropical primary forest in Mexico and Central America. I generally concur with this assessment, as no obvious extensive habitat changes seem to have occurred to its breeding habitat in the Sierra. The more open meadow/willow habitat of the Willow Flycatcher has been heavily impacted by grazing, but the Swainson's Thrushes that are or were present at some of these same meadows occupy(ied) the dense, shady edges of forest where grazing has much less of an impact. Nevertheless, grazing and associated cowbird parasitism could have played a role in the disappearance of the Swainson's Thrush. The species may now be so rare in the Sierra that birds may have difficulty in finding mates. An apparently unmated male Swainson's Thrush, for example, sang at Hodgdon Meadow in Yosemite National Park and was captured in the MAPS nets there in both 1990 and 1991. No mate or young, however, were ever seen, heard, or captured there. MAPS data overall, however, suggest that problems on the breeding grounds could also be contributing to the decline of this species. No young have ever been captured in MAPS nets at the three stations at which they occurred, despite the fact that a total of 22 individual adults were captured at these stations. Both males and females were simultaneously present in at least some years at two of the stations, Zumwaldt Meadow in Kings Canyon National Park and the Sierra Nevada Field Campus in the Tahoe National Forest. I can suggest no obvious reason for poor productivity at these stations or in the Sierra in general. Unfortunately, Sierran MAPS data on this rare species is too sparse to produce reliable estimates of adult survival rates for Sierran birds. Adding to the mystery, is the fact that east slope birds also seem to be declining despite the fact that they represent a different subspecies that winters in South America rather than in Mexico and Central America. Obviously, extensive work needs to be conducted on this species if it is to remain a viable component of the Sierran avifauna.
HERMIT THRUSH - Cartharus guttatus
Stat: NTM West: fS,uT,rW. East: fS,uT,rW.
Dist: T West: N:5-10; T:F-10; W:F-3. East: N:7-10; T:B-10; W:B-7.
Sign: CAN-WMT-3Ssp. sequoiensis - PCAL-11. Except for uncommon, local populations on some of the southern California mountains, this subspecies is limited entirely to the Sierra Nevada. Because populations in the Sierra are typically quite high, the Sierra is of extremely great importance to the survival of this subspecies which could very nearly be classified as a Sierran endemic. Although other races of Hermit Thrushes (gutttata, nana, and possibly slevini) migrate and winter in the Sierra, sequoiensis winters virtually entirely in Mexico and is rightly considered a Neotropical migrant.
Hab: R: 3-MHW,MHC,DFR,MCN,RFR,LPN,SCN,EPN,MRI; 2-PPN,JPN.
F: 3-MHW,MHC,PPN,DFR,MCN,JPN,RFR,LPN,SCN,EPN,MRI; 2-ASP,PJN,JUN,MCP,RSP.
Sp: At mid-elevations on the west slope prefers dense, shady, mostly mature mixed conifer and red fir forests but occurs less commonly in mixed hardwood-conifer and Douglas fir forests. At higher elevations and on the east slope, occurs in more open lodgepole pine, subalpine conifer, and aspen forests.
Abundance: BBS: 16 routes;6. 40 birds/route. MAPS: 1. 71 ad/600 nh
Trends: BBS: PI; 2. 2% per year
Demographics: MAPS: Prod. index: 31. 2% yg.
Potential risks and suggested causes of population trends: In sharp contrast to Swainson's Thrush, Hermit Thrush shows a possibly increasing trend of 2. 2% per year. The species typically winters in Mexico in more temperate montane habitats than Swainson's Thrush and, thus, currently may be less affected than Swainson's Thrush by deforestation on its wintering grounds. Logging of mid-elevation Sierran forests, especially old-growth and dense mature forests, is a major risk. Selective logging of higher elevation and east slope forests may present a smaller risk as the species regularly occurs there in more open forest.
AMERICAN ROBIN - Turdus migratorius
Stat: SDM West: cS,ifW. East: cS,ifW.
Dist: T West: N:F-10; W:F-4. East: N:B-10; W:B-8.
Sign: CONT-1. Ssp. propinquus - WEST-4. Robins are common and widespread in the Sierra which represents an important part of their range in California and a reasonably important part of the range of the subspecies propinquus.
Hab: R: 3-MHW,MHC,PPN,DFR,MCN,JPN,LPN,MRI,RSP; 2-RFR,SCN,ASP,EPN.
F: 3-MHW,MHC,PPN,DFR,MCN,JPN,LPN,WTM,MRI,MCP,RSP; 2-FR,SCN,ASP,EPN,PJN, JUN,PAS.
Sp: Requires moist tree-margined meadows, pastures, or lawns at virtually any elevation and in association with virtually any forest type. Requires a source of mud for nest building. Responds very favorably to the lawns and gardens around human habitations. Requires substantial crops of berries for winter sustenance.
Abundance: BBS: 17 routes; 32. 06 birds/route. MAPS: 3. 25 ad/600 nh
Trends: BBS: DD;-3. 1% per year***
Demographics: MAPS: Prod. index: 28. 4% yg.
Potential risks and suggested causes of population trends: Here is another of the ten Sierran landbirds that is definitely decreasing in the Sierra. Considering its widespread, nearly ubiquitous distribution and generally high abundance in the Sierra, this is a most surprising result. Perhaps the drought conditions that have often prevailed over the past 20 years has negatively impacted this species, which requires moist habitat for foraging and nest-building. It is also possible that drought conditions (and perhaps even the extreme El Nino conditions that occurred in 1982 and 1983) adversely affected the Sierra's berry crops, this species' major winter food source. This latter possibility is complicated because the robin populations wintering in the Sierra may not be the same populations that breed there. Other than extensive clearcutting, most logging operations may not greatly adversely affect robin populations. Extensive grazing that causes stream channelization will cause a general drying out of meadows which could adversely affect this species. Other risks are hard to suggest.
Stat: R West: cR,rT. East:
Dist: W West: N:F-5; T:F-7; W:F-5. East:
Sign: CAL-10. Also breeds in western Oregon and northwestern Baja California, so not entirely restricted to California. However, CAL-10 still represents the best importance classification. Ssp. henshawi - CAL-10 is probably a better classification than PCAL-11.
Hab: R: 2-MCP,RSP.
F: 2-MCP,RSP.
Sp: Requires dense brushland. Most common in dense hard chaparral,especially dense chamise, ceanothus, and poison oak.
Abundance: BBS: 10 routes;0. 75 birds/route. MAPS:
Trends: BBS: IT;2. 32% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Loss of foothill chaparral to development is a risk, as is the occurrence catastrophic fires due to years of fire suppression. The species, however, shows an increasing tendency in the Sierra.
SAGE THRASHER - Oreoscoptes montanus
Stat: SDM West: xT. East: rS?.
Dist: T West: T:4-9. East: N:B-8?.
Sign: RM/GB-8. This species nests commonly throughout the sagebrush east of the eastern base of the Sierran escarpment, but does not seem to nest in the sagebrush that covers the east slope of the Sierra except, perhaps, along the southeastern flank of the Sierra. In fact, there seems to be no record of this species actually on the east slope of the Sierra in the Yosemite region (Gaines 1988). Thus, like the Pinyon Jay, this species may not nest in the Sierra proper. At any rate, the Sierra is of negligible importance to the species' overall population.
Hab: R:
F: 2-JUN.
Sp: Requires sagebrush covered flats or gently rolling hills. Apparently does not occur on steep slopes even if the habitat is otherwise perfect.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: I can suggest no risks to this species on its breeding ground. However, the species may be impacted by loss of grassland habitat on its wintering grounds, although the impact should be less than for species that are more restricted to grassland habitats. No trend data exist for the this species in the Sierra.
CALIFORNIA THRASHER - Toxostoma redivivum
Stat: R West: lfR. East:
Dist: T West: N:F-3; W:F-3. East:
Sign: CAL-10. Ssp. sonomae northern part of west slope - PCAL-11; redivivum southern part of west slope -PCAL-11. Despite the fact that this species is not widely distributed in the Sierra, the foothills of the Sierra do constitute a significant portion of the overall range of this species, especially for the northern race sonomae. Thus, populations in the Sierra should be monitored closely.
Hab: R: 2-MCP,RSP,[MRI].
F: 2-MCP,RSP,[MRI].
Sp: Restricted to dense chaparral and, to a lesser degree, adjacent dense riparian habitats, and edges of dense live oak woodlands. Adapts, to some extent, to the neighborhood of human habitations provided considerable cover is maintained.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: Loss of habitat to development in the foothills is an important risk. Decreased production of foothill berry crops due to drought conditions could be another problem.
EUROPEAN STARLING - Sturnus vulgaris
Stat: SDM West: lcS,uW. East: lcS,lfW.
Dist: T West: N:F-5; W:F-4. East: N:B-8; W:B-7.
Sign: CONT-1. Starling populations in the Sierra are generally only a fraction of what they are in most other areas of their range, so the Sierra is not of great importance to their overall population.
Hab: R: 3-RSP; 2-MHW,MHC,PPN,PJN,JUN,MRI.
F: 3-WTM,PAS,RSP; 2-MHW,MHC,PPN,ASP,PJN,JUN,MRI.
Sp: Closely associated with human habitats such as urban and suburban areas, ranches, agricultural and pastoral areas, garbage dumps, and low-elevation campgrounds. Generally does not utilize areas remote rom human habitation except for nesting. Cavity nester that readily evicts most species from nests that it appropriates for its own use.
Abundance: BBS: 7 routes;2. 68 birds/route. MAPS:
Trends: BBS: IT; 5. 7% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Populations have shown a steady and dramatic increase since their invasion of California, first reported in 1942. Their invasion of the Sierra began in earnest in the 1960s and is apparently continuing to this day; the species shows an increasing tendency of 5. 7% per year on the seven Sierran BBS routes on which it occurred. Increased human use of the Sierra in all ways, especially increased residential development, and increased adaptation of the species to human habitations at ever-increasing altitudes are probably the major factors effecting its increase. I can identify no risks that this species faces. To the contrary, the presence of starlings can be a risk to numerous other cavity nesting species.
AMERICAN PIPIT - Anthus rubescens
Stat: SDM West: luS,rT,xW. East: luS,uT.
Dist: CSWest: N:10-12; T:F-12; W:F-5. East: N:10-12; T:B-12.
Sign: CAN-WMT-3. Ssp. alticola - RM/GB-8. American Pipits have apparently only recently colonized the alpine regions of the central and southern Sierra as all high country records prior to the 1970s occurred between late August and October, when transients would be expected. Old July records, however, exist for both Mt. Shasta and Mt. Lassen (Grinnell and Miller 1944). The racial identity of the pipits breeding in the Sierra has been ascertained by Miller and Green (1987) as alticola, the race breeding in the Great Basin and central Rocky Mountains. Although pipits are relatively uncommon in the alpine Sierra, this major range extension is of great importance to the overall distribution and population of the alticola subspecies. Except for several pairs breeding on the summit of Mt. San Gregorio in southern California, theentire breeding range of American Pipit in California lies in the alpine Sierra. It is critical, therefore, that the population of breeding pipits in the Sierra be monitored, at least at relatively infrequent intervals.
Hab: R: 3-ADS.
F: 3-WTM,ADS,BAR,PAS.
Sp: Requires moist alpine meadows, most often in the vicinity of lakes or tarns.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: Miller and Green (1987) suggest that American Pipits might have been eliminated from the Sierra during the most recent xerothermic period, 3,000 to 5,000 years ago, and that chance dispersal or prior colonization of the Great Basin ranges has allowed the species to recolonize the Sierra now that cooler and wetter conditions prevail. It is not clear at present whether pipits are increasing or decreasing in the Sierra, but casual observations in the Hall Natural Area suggest smaller numbers during the recent drought years (1987-1994) than during earlier wetter years (1978-1986) (DeSante pers. observ. ). Other than climate factors, I can suggest no risks that this species might be facing in the Sierra.
PHAINOPEPLA - Phainopepla nitens
Stat: R-SDM West: iuS,xT,irW. East: irS,xT.
Dist: TW,SE West: N:F-2; T:F-8; W:F-2. East: N:B-7; T:B-8.
Sign: SW-9. Ssp. lepida -SW-9. Phainopeplas are generally uncommon breeders in the Sierra which, therefore, constitutes a relatively unimportant part of the species overall range. However, the foothills of the Sierra constitute a relatively important part of the species' northern California range, so attempts to monitor the species in the Sierra should be made.
Hab: R: 3-RSP; 2-[MHW].
F: 3-RSP; 2-[MHW].
Sp: Requires open woodlands or scattered groves of small trees. Utilizes both oak woodland (live and blue oak) and riparian woodland. A special requirement, especially in the non-breeding season, is the presence of berries, particularly mistletoe berries and, to a lesser extent, elderberries.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: No population trend data exist for the Sierra, but loss of foothill oak habitat and poor productivity of berry crops during drought conditions are potential risks.
ORANGE-CROWNED WARBLER - Vermivora celata
Stat: SD-NTMWest: cS,cT. East: uS*,cT.
Dist: T West: N:F-4; T:F-11. East: N:6-8?; T:B-11.
Sign: CAN/WMT-3 (although occurs outside montane habitat over some of the western states). Ssp. lutescens west slope - PAC-7; orestera may breed locally on central portion of east slope, but positive evidence of breeding is still lacking. While a common breeder at low elevations on the west slope, Sierran breeding populations are probably relatively small compared to coast range populations. Extremely abundant, however, as a summer visitor to higher elevations in the Sierra, often outnumbering all other species. Thus, the Sierra may be of critical importance for molting and pre-migratory maintenance for this species.
Hab: R:
F: 3-MHW,MHC,MRI,MCP,RSP; 2-PPN,MCN,JPN,RFR,LPN,[SCN],ASP,EPN.
Sp: Limited to rather open to moderately dense, brushy woodlands at lower elevations for nesting. Shows a preference for interior live oak woodland, but also nests in canyon oak and blue oak woodland, especially if mixed with chaparral or other brush, and even in arborescent chaparral in the absence of woodland. Occurs in all habitats during up-mountain drift, but reaches greatest abundance in montane meadows and montane riparian situations where it is often the commonest species. Locations of suspected possible breeding on the central east slope are in streamside willows and aspens in the lower reaches of the major canyons.
Abundance: BBS: 15 routes;1. 91 birds/route. MAPS:
Trends: BBS: PD; -1. 8% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: Loss of oak woodland and chaparral habitat on the lower west slope is a risk; as is, to a lesser extent, cowbird parasitism. Loss of montane meadow and riparian habitat or degradation of this habitat by grazing is a serious risk. BBS data indicate that Sierran populations may be declining.
NASHVILLE WARBLER - Vermivora ruficapilla
Stat: NTM West: cS,fT. East: rS*,uT.
Dist: T West: N:3-6; T:F-11. East: N:6-9?; T:B-11.
Sign: CAN/WMT-3 (but absent from most of the Rocky Mountains and Great Basin where replaced by Virginia's Warbler). Ssp. ridgwayi - PAC-7. Verycommon in the Sierra which represents a very important part of this subspecies' range. Like the Orange-crowned Warbler, drifts up-slope in large numbers after the breeding season. May breed locally on the central part of the east slope, but there is no confirmed breeding record, although birds carrying food have been seen in Lee Vining Canyon (Gaines 1988).
Hab: R: 3-MHW,MHC,PPN,MCN,MRI,MCP.
F: 3-MHW,MHC,PPN,MCN,MRI,MCP,RSP; 2-DFR,JPN,RFR,LPN,ASP.
Sp: Prefers black oaks, canyon oaks, and maples mixed with conifers, particularly ponderosa pine and mixed conifers. Prefers relatively dry, rather open forest with a well developed shrubby understory. Upslope dispersal carries birds into virtually all habitats, although largest concentrations occur in montane meadows and montane riparian habitat.
Abundance: BBS: 15 routes;8. 89 birds/route. MAPS: 3. 61 ad/600 nh
Trends: BBS: PD; -2. 9% per year
Demographics: MAPS: Prod. index: 71. 3% yg.
Potential risks and suggested causes of population trends: Risks include forestry practices that remove or limit the requisite deciduous-conifer-brush combination that it prefers; loss or degradation of montane meadows and montane riparian habitat due to forestry practices and/or grazing is a major risk. Cowbird parasitism is also a risk. BBS data indicate a possibly decreasing population trend. The high MAPS productivity index may be an artifact of the large numbers of young that disperse up-slope.
VIRGINIA'S WARBLER - Vermivora virginiae
Stat: NTM West: xT. East: lirS,lrT.
Dist: T West: T:4-6. East: N:6-9; T:6-10.
Sign: RM/GB-8. Probably a recent colonist with a very tenuous foothold in the Sierra where it is very rare and irregular. Thus, the Sierra does not comprise an important part of the species range. However, the breeding range in California is limited to the White, Clark, New York, and occasionally, the northeastern San Bernardino Mountains and the species is quite uncommon; thus, the Sierra could become important for the species survival in California.
Hab: R: 3-MCP; 2-[EPN].
F: 3-MCP; 2-[EPN].
Sp: In the Sierra, prefers open woodlands of pinyon pine and mahoganymixed with tracts of shrubs; also occurs in riparian thickets.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS
Potential risks and suggested causes of population trends: Probably a recent colonist to the Sierra that is irregular in numbers from year to year. No trend data are available. Cowbird parasitism is a major risk.
YELLOW WARBLER - Dendroica petechia
Stat: NTM West: cS,xT. East: cS,xT.
Dist: T West: N:F-6; T:F-9. East: N:B-8; T:B-10.
Sign: CONT-1. Ssp. brewsteri west slope and northern and north-central portions of east slope - PAC-7; morcomi south-central and southern portions of east slope - RM/GB-8. AOU (1957) does not recognize brewsteri and merges it with morcomi, which would then be WEST-4.
Hab: R: 3-(PPN),(MCN),MRI,(MCP).
F: 3-PPN,MCN,MRI,MCP,RSP; 2-MHW.
Sp: Generally requires riparian habitat, particularly willows, cottonwoods, aspens, and alders, or willows in montane meadows. However, has apparently recently begun to adapt to dry, dense montane chaparral with only a few scattered trees and to monocultural tracts of re-seeded pine seedlings about six-feet tall.
Abundance: BBS: 16 routes;5. 62 birds/route. MAPS: 4. 18 ad/600 nh
Trends: BBS: PD; -3. 3% per year
Demographics: MAPS: Prod. index: 39. 8% yg. Ann. surv. rate: 0. 804 (0. 139);
Cap. prob. : 0. 672 (0. 120).
Potential risks and suggested causes of population trends: Loss of montane riparian habitat and degradation of montane meadows due to grazing are very serious risks. Cowbird parasitism is also a serious risk as this species is a favorite host species. May be adapting to the kind of vegetative growth that often develops after fires or clearcutting and to the early stages of pine plantations. If this adaptation is real and successful, some forestry practices that are deleterious to most species could be favorable to this species. Given the possibly decreasing trend, however, this is a species that should be monitored very closely.
YELLOW-RUMPED WARBLER - Dendroica coronata
Stat: SD-NTMWest: cS,cT,uW. East: cS,cT,rW.
Dist: T West: N:4-10; T:F-10; W:F-4. East: N:6-10; T:B-10; W:B-7.
Sign: CAN-WMT-3. Ssp. auduboni throughout the Sierra - PAC-7. Grinnell and Miller (1944) did not recognize memorabilis which AOU (1957) recognizes as breeding in the White and Inyo Mountains east of the Sierra. Grinnell and Miller included memorabilis in auduboni which would then have an importance classification of WMT-6. Regardless, Yellow-rumped Warblers are very common in the Sierra which constitutes an important part of their range.
Hab: R: 3-MHC,PPN,DFR,MCN,JPN,RFR,LPN,EPN; 2-SCN,ASP,PJN,MRI.
F: 3-MHW,MHC,PPN,DFR,MCN,JPN,RFR,LPN,ASP,EPN,MRI,RSP; 2-SCN,PJN,MCP,PAS.
Sp: Occurs in almost all varieties of conifer forests, in dense, shady situations as well as in dry, open situations, from ponderosa pine and Douglas fir forests up through subalpine conifers and down through eastside pine forests; notably less common in pinyon pines, however. Post-breeding dispersal concentrates many birds, particularly young, in montane meadows and montane riparian habitat.
Abundance: BBS: 17 routes; 15. 63 birds/route. MAPS: 5. 83 ad/600 nh
Trends: BBS: DS; 0. 3% per year
Demographics: MAPS: Prod. index: 68. 9% yg. Ann. surv. rate: 0. 883 (0. 218); Cap. prob. : 0. 280 (0. 123).
Potential risks and suggested causes of population trends: Because of its wide tolerance of varying conifer habitats, may be less affected by logging operations than some other warbler species; however, it is still a forest species and, as such, is dependent on the existence of, at least, an open forest. Loss and degradation of montane meadow and montane riparian habitat through grazing and other causes could be an important risk to dispersing young. As with most warblers, cowbird parasitism is a potential risk. BBS data indicate a definitely stable trend.
BLACK-THROATED GRAY WARBLER - Dendroica nigrescens
Stat: NTM West: cS,rT. East: rT.
Dist: T West: N:3-7; T:F-10. East: T:B-10.
Sign: WMT-6. Surprisingly, does not breed on the east slope of the Sierra. While common in suitable habitat in the Sierra, the Sierra plays a less important role for the overall population of this species than for most other montane warblers.
Hab: R: 3-MHW,MHC,PPN; 2-(PJN),(JUN).
F: 3-MHW,MHC,PPN; 2-MCN,PJN,JUN,MRI.
Sp: Prefers dry, sunny slopes, and open forest or woodland. Canyon oak is the preferred tree species, but also occurs readily in black oaks and ponderosa pines and uncommonly in Douglas firs and mixed conifers. Generally prefers a brushy understory of montane chaparral. While the species is quite common in pinyon pine and juniper habitat in the Great Basin ranges east of the Sierra, it apparently does not breed anywhere on the east slope of the Sierra. Post-breeding up-slope dispersal does not carry many birds much beyond the elevations of their breeding grounds and they are generally rare in montane meadows.
Abundance: BBS: 12 routes;3. 77 birds/route. MAPS: 0. 22 ad/600 nh
Trends: BBS: PS; 0. 1% per year Demographics: MAPS:
Potential risks and suggested causes of population trends: Its preference for canyon oaks and dry open forest makes this species potentially less adversely affected by most logging practices than many other warblers. Loss and degradation of montane meadows and montane riparian habitat may also be less of a risk than for other warblers. Loss of habitat to development, especially at the lower elevation stronghold of its range, could be a major risk, as is cowbird parasitism, especially where development encroaches on its breeding habitat.
HERMIT WARBLER - Dendroica occidentalis
Stat: NTM West: cS,uT. East: rT.
Dist: T West: N:4-8; T:F-10. East: T:9-10.
Sign: PAC-7. Populations of this species are very high in the Sierra, which represents an extremely important part of the species' overall range.
Hab: R: 3-MHC,PPN,DFR,MCN,JPN,RFR; 2-(MHW).
F: 3-MHC,PPN,DFR,MCN,JPN,RFR; 2-MHW,LPN,MRI,RSP.
Sp: Prefers relatively dense, shady, mostly mature conifer-dominated forest at mid-elevations. Preferred tree species are white, red, and Douglas firs, and sugar and ponderosa pines.
Abundance: BBS: 17 routes;10. 03 birds/route. MAPS: 5. 50 ad/600 nh
Trends: BBS: LS; -0. 7% per year
Demographics: MAPS: Prod. index: 55. 6% yg.
Potential risks and suggested causes of population trends: Because this species prefers mature, rather dense conifer forest, it is highly susceptible to most logging practices which could present a serious risk to the species. Congregates to some extent in montane meadows and montane riparian habitats during up-mountain dispersal, so degradation of these habitats presents at least a small risk. Like most warblers, cowbird parasitism also presents a risk. Despite these threats, shows a likely stable BBS trend.
MACGILLIVRAY'S WARBLER - Oporornis tolmiei
Stat: NTM West: fS,fT. East: fS,fT.
Dist: T West: N:3-8; T:F-10. East: N:6-8; T:B-10.
Sign: WMT-6. Ssp. tolmiei throughout the Sierra - WTM-6 (but absent from much of the central and southern Rocky Mountains and Great Basin where replaced by monticola, which, however, was not recognized by Grinnell and Miller [1994]). Other subspecies have been described and perhaps occur in the Sierra, but I am not familiar with the literature on them. This species is very common in the Sierra which constitutes an important part of the species' range.
Hab: R: 3-(DFR),MRI; 2-[MHC],[MCN],[RFR].
F: 3-(DFR),MRI; 2-[MHC],[MCN],[JPN],[RFR],[LPN],[SCN],[EPN],MCP.
Sp: Prefers moist montane riparian thickets, the margins of montane meadows, and the shrubby understories of moist, generally dense forests. Occurs commonly in up-slope dispersal and, perhaps even more commonly, in migration in montane meadows and montane riparian habitat at higher elevations.
Abundance: BBS: 15 routes;4. 46 birds/route. MAPS: 12. 54 ad/600 nh
Trends: BBS: LS; -0. 6 per year
Demographics: MAPS: Prod. index: 51. 0% yg. Ann. surv. rate: 0. 508 (0. 078);
Cap. prob. : 0. 679 (0. 090).
Potential risks and suggested causes of population trends: The loss and degradation of montane riparian habitat and montane meadows due to grazing and other causes is a serious risk. Logging practices that open-up dense moist forest or destroy the shrubby understory of such forests also provide a serious risk. Encroaching development into the lower elevations of its breeding range, and the cowbird parasitism that can be associated with such development are also risks. The likely stable BBS trend for this species is similar to that for Hermit Warbler.
COMMON YELLOWTHROAT - Geothylpis trichas
Stat: SD-NTMWest: rS?,rT. East: rS*,rT.
Dist: T West: N:F-7?; T:F-7. East: N:B-7?; T:B-10.
Sign: CONT-1. Ssp. arizela west slope - PAC-7; occidentalis east slope - RM/GB-8. Grinnell and Miller (1944) did not recognize arizela and merged it with occidentalis. If this taxonomy is followed then the appropriate importance classification of the expanded occidentalis would be WUS-5 (although the subspecies is absent from the Southwest). Although this species breeds in marshes in the Central Valley and east of the eastern base of the Sierran escarpment, there may not be any valid breeding records in the Sierra proper, except, perhaps, for the lowest foothills of the west slope. Nevertheless, territorial males have been present for extended periods in summer on both the east and west slopes of the Sierra, so breeding is possible. Regardless, the Sierra is very unimportant to the species' overall population, both in California and continent-wide.
Hab: R: 3-WTM,MRI.
F: 3-WTM,MRI.
Sp: Generally restricted to moist situations with low dense cover; prefers cattails, bulrushes, sedges, and willow thickets, especially in or bordering marshes, ponds, and wet meadows.
Abundance: BBS: MAPS:
Trends: BBS:
Demographics: MAPS:
Potential risks and suggested causes of population trends: Loss and degradation of marshes, wet meadows, and dense riparian habitats due to grazing and other causes is a very serious risk. Flooding (or drying-up) of the lower reaches of foothill river valleys due to dam construction and water diversion is also a major risk. This species is also very susceptible to cowbird parasitism, especially in areas where grazing comes in contact with their habitat.
WILSON'S WARBLER - Wilsonia pusilla
Stat: NTM West: uS,cT. East: uS,cT.
Dist: T West: N:4-10; T:F-11. East: N:8-10; T:B-11.
Sign: CAN/WMT-3. Ssp. chryseola throughout Sierra - PAC-7. The pilealata race occurs commonly as a migrant in the Sierra, especially on the east
slope, but does not breed in the Sierra. Sierran populations of this species are considerably smaller than populations in the coast ranges; thus the Sierra may be less importance to this species than certain other PAC-7 species.
Hab: R: 3-ASP,MRI; 2-[MHC],[DFR],[MCN],[RFR],LPN,[SCN].
F: 3-ASP,MRI,RSP; 2-MHW,MHC,PPN,DFR,MCN,JPN,[RFR],LPN,[SCN],EPN,MCP.
Sp: At mid-elevations, generally restricted to moist montane riparian habitat and moist deciduous trees and thickets on the edges of montane meadows; less commonly in the moist understory of humid, mature coniferous forests. At high elevations and on the east slope occurs most commonly in the willows of montane meadows, on moist, willow-covered subalpine slopes, and in riparian aspen woodlands. Up-slope dispersal and migration concentrates large numbers in the willows of montane meadows.
Abundance: BBS: 13 routes;1. 95 birds/route. MAPS: 8. 82 ad/600 nh
Trends: BBS: DT;-6. 2% per year
Demographics: MAPS: Prod. index: 54. 8% yg. Ann. surv. rate: 0. . 458 (0. 095);
Cap. prob. : 0. 665 (0. 117).
Potential risks and suggested causes of population trends: Loss and degradation of montane riparian habitats and montane meadows due to grazing and other causes is a serious risk. Forestry practices that eliminate or degrade humid mature and old-growth forest is another serious risk. The species is also very susceptible to cowbird parasitism which is another serious risk. Except for Common Yellowthroat, this species seems more dependent on humid conditions than any other warbler; thus drying climate trends could present another risk. Because the species also shows a negative trend over western U. S. as a whole, its Sierran populations should be very carefully monitored.
YELLOW-BREASTED CHAT - Icteria virens
Stat: NTM West: rS,xT. East: rT?.
Dist: T West: N:F-2; T:F-4. East: T:B-7.
Sign: US-2. Ssp. auricollis - WUS-5. Although the species occurs east of the eastern base of the Sierran escarpment as a rare breeder in the Owens Valley and as a rare transient north at least to the Mono Basin, I know of no definite records of breeders or transients on the east slope of the Sierra proper, although I suspect that it does occur rarely as a transient in the lower reaches of the major canyons draining the east slope.
Hab: R:
F: 2-MRI.
Sp: Restricted to low, dense riparian growth, primarily willow thickets and tangles of blackberries and tall weeds, in the lower foothills of the west slope.
Abundance: BBS: 2 routes;0. 23 birds/route. MAPS:
Trends: BBS: UN;3. 5% per year
Demographics: MAPS:
Potential risks and suggested causes of population trends: This species has decreased drastically along the rivers and streams in the lower foothills of the west slope over the last 50 years, primarily due to dams, water diversions, and logging of riparian forests. Whereas Grinnell and Miller (1944) considered it fairly common, now it is rare at best. Because of the sparseness of the data, the Sierran BBS population trend must be considered unknown. Serious continued risks include further loss and degradation of riparian habitats to residential, commercial, and agricultural development, water projects, and grazing; and cowbird parasitism.
WESTERN TANAGER - Piranga ludoviviana
Stat: NTM West: fS,uT. East: fS,uT.
Dist: T West: N:3-8; T:F-10. East: N:6-8; T:B-10.
Sign: WMT-6. This species is quite common in the Sierra which, therefore, plays an important role in its overall range.
Hab: R: 3-(MHW),MHC,PPN,MCN,JPN,RFR,[EPN],MRI; 2-DFR,PJN.
F: 3-MHW,MHC,PPN,MCN,JPN,RFR,[EPN],MRI,RSP; 2-DFR,PJN.
Sp: Favors relatively open forest with a mixture of trees, but seems tooccur commonly in both dry and moist conditions. Tends to avoid both extremely dense, closed forests and very open woodland situations. Occurs widely in coniferous forests of most kinds(digger, lodgepole, and pinyon pines are usually avoided for nesting), and in mixed hardwood, aspen, and riparian forests, but,in the latter situations, usually requires the presence of at least a few conifers of some kind.
Abundance: BBS: 17 routes; 20. 06 birds/route. MAPS: 2. 51 ad/600 nh
Trends: BBS: DS; -0. 4% per year
Demographics: MAPS: Prod. index: 43. 4% yg.
Potential risks and suggested causes of population trends: Risks include extensive logging operations, although, because Western Tanagers tend to prefer relatively open forests, some kinds of logging practices may not be totally detrimental. Loss of montane riparian habitat could be a relatively minor factor as could cowbird parasitism. BBS data, however, indicate thatWestern Tanager populations are stable in the Sierra.
GREEN-TAILED TOWHEE - Pipilo chlorurus
Stat: NTM West: uS,rT. East: fS,uT.
Dist: T West: N:5-8; T:F-10. East: N:5-9; T:B-10.
Sign: RM/GB-8. This species is much less common in the Sierra (especially on the west slope) than in many other parts of its range; thus, the Sierra is less important to its overall populations than for many other RM/GB-8 species.
Hab: R: 3-MHW,MHC,(PPN),(MCN),PJN,MCP; 2-(DFR),JUN,MRI.
F: 3-MHW,MHC,PPN,MCN,PJN,MCP; 2-(DFR),JUN,MRI.
Sp: The presence of montane chaparral is a firm requisite for this species. It can be mixed with coniferous forest but only if the forest is sparse and the site is dry and well insolated. On the east slope, where it is much more common, mountain mahogany mixed with sagebrush is preferred. Up-mountain dispersal carries birds into montane riparian and wet meadow habitats.
Abundance: BBS: 12 routes;3. 44 birds/route. MAPS: 0. 40 ad/600 nh
Trends: BBS: LD;-3. 9% per year**
Demographics: MAPS: Prod. index: 27. 3% yg.
Potential risks and suggested causes of population trends: Catastrophic fires and extensive logging operations may be a temporary risk, but could also serve to increase the species total population. Loss and degradation of montane riparian and meadow habitat could adversely affect up-mountain dispersers. Cowbird parasitism is a serious risk. The species' Sierranpopulations are likely decreasing. Perhaps, problems on the wintering rangein southern Arizona and northern Mexico may be responsible.
SPOTTED TOWHEE - Pipilo maculatus
Stat: R-SDM West: cS,rT,cW. East: uS,rT,uW.
Dist: T West: N:F-6; T:F-10; W:F-5. East: N:B-8; T:B-10; W:B-7.
Sign: CONT-1. Ssp. falcinellus west slope and southern portion of east slope - PCAL-11; curtatus northern and central portions of east slope - RM/GB-8.
Hab: R: 3-MCP,RSP; 2-MHW,MHC,PPN,DFR,MCN,EPN,PJN,JUN,MRI.
F: 3-MCP,RSP; 2-MHW,MHC,PPN,DFR,MCN,EPN,PJN,JUN,MRI.
Sp: Favors large, relatively dense thickets or shrubs with accumulations of leaf litter. On the west slope, prefers arid foothill chaparral, montane chaparral, and shrubby understories of open woodland and forest, particularly oak woodland and ponderosa pine forest; generally occurs in riparian situations only in the lowest foothills. On the east slope, prefers relatively dense and tall brush, often in ravine and canyon bottoms and at the bases of cliffs; often associated with riparian willow thickets and with scattered pinyons, junipers, and mountain mahoganies.
Abundance: BBS: 16 routes;8. 55 birds/route. MAPS: 0. 29 ad/600 nh
Trends: BBS: PI; 1. 7% per year
Demographics: MAPS: Prod. index: 45. 5% yg.
Potential risks and suggested causes of population trends: Most forestry practices and even catastrophic fires could be favorable or, at least, not very detrimental, to this species. Lack of strong association with riparian habitat and montane meadows (at least on the west slope) eliminates risks common to many other Sierra species. Cowbird parasitism remains a relatively small risk. Thus, it is not surprising that possible increase of 1. 7% per year has been recorded on BBS routes.