Sitta pygmaea - Vigors, 1839
Pygmy Nuthatch
Other English Common Names: pygmy nuthatch
Taxonomic Status: Accepted
Related ITIS Name(s): Sitta pygmaea Vigors, 1839 (TSN 178788)
French Common Names: Sittelle pygmée
Spanish Common Names: Sita Enana
Unique Identifier: ELEMENT_GLOBAL.2.100063
Element Code: ABPAZ01030
Informal Taxonomy: Animals, Vertebrates - Birds - Perching Birds
Image 10772

© Dick Cannings

 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Aves Passeriformes Sittidae Sitta
Genus Size: D - Medium to large genus (21+ species)
Check this box to expand all report sections:
Concept Reference
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Concept Reference: American Ornithologists' Union (AOU). 1998. Check-list of North American birds. Seventh edition. American Ornithologists' Union, Washington, D.C. [as modified by subsequent supplements and corrections published in The Auk]. Also available online: http://www.aou.org/.
Concept Reference Code: B98AOU01NAUS
Name Used in Concept Reference: Sitta pygmaea
Taxonomic Comments: Constitutes a superspecies with and has been considered conspecific with S. pusilla by some authors (AOU 1983, 1998).
Conservation Status
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NatureServe Status

Global Status: G5
Global Status Last Reviewed: 09Apr2016
Global Status Last Changed: 02Dec1996
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Nation: United States
National Status: N5 (05Jan1997)
Nation: Canada
National Status: N4N5 (03Jan2018)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Arizona (S5), California (SNR), Colorado (S4), Idaho (S4), Montana (S4), Navajo Nation (S5), Nebraska (S3), Nevada (S3), New Mexico (S3B,S3N), Oregon (S4), South Dakota (S2S3), Texas (S3B), Utah (S3S4), Washington (S3S4), Wyoming (S2)
Canada British Columbia (S4)

Other Statuses

IUCN Red List Category: LC - Least concern

NatureServe Global Conservation Status Factors

Range Extent Comments: RESIDENT: southern interior British Columbia, northern Idaho, western Montana, central Wyoming and southwstern South Dakota south to northern Baja California, southern Nevada, central and southeastern Arizona, central New Mexico, extreme western Texas and extreme western Oklahoma, south in mountains to cental Mexico (AOU 1983). To elevations of 3000 m.

Other NatureServe Conservation Status Information

Protection Needs: See Thomas et al. (1993) for recommendations for the Pacific Northwest.

Distribution
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Global Range: RESIDENT: southern interior British Columbia, northern Idaho, western Montana, central Wyoming and southwstern South Dakota south to northern Baja California, southern Nevada, central and southeastern Arizona, central New Mexico, extreme western Texas and extreme western Oklahoma, south in mountains to cental Mexico (AOU 1983). To elevations of 3000 m.

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
NOTE: The maps for birds represent the breeding status by state and province. In some jurisdictions, the subnational statuses for common species have not been assessed and the status is shown as not-assessed (SNR). In some jurisdictions, the subnational status refers to the status as a non-breeder; these errors will be corrected in future versions of these maps. A species is not shown in a jurisdiction if it is not known to breed in the jurisdiction or if it occurs only accidentally or casually in the jurisdiction. Thus, the species may occur in a jurisdiction as a seasonal non-breeding resident or as a migratory transient but this will not be indicated on these maps. See other maps on this web site that depict the Western Hemisphere ranges of these species at all seasons of the year.
Endemism: occurs (regularly, as a native taxon) in multiple nations

U.S. & Canada State/Province Distribution
United States AZ, CA, CO, ID, MT, NE, NM, NN, NV, OR, SD, TX, UT, WA, WY
Canada BC

Range Map
Note: Range depicted for New World only. The scale of the maps may cause narrow coastal ranges or ranges on small islands not to appear. Not all vagrant or small disjunct occurrences are depicted. For migratory birds, some individuals occur outside of the passage migrant range depicted. For information on how to obtain shapefiles of species ranges see our Species Mapping pages at www.natureserve.org/conservation-tools/data-maps-tools.

Range Map Compilers: NatureServe, 2002; WILDSPACETM 2002


U.S. Distribution by County Help
State County Name (FIPS Code)
NE Cherry (31031), Dawes (31045), Sioux (31165)
SD Bennett (46007), Custer (46033), Fall River (46047), Pennington (46103)*
WY Albany (56001), Big Horn (56003), Carbon (56007), Converse (56009), Crook (56011), Fremont (56013), Hot Springs (56017), Johnson (56019), Laramie (56021), Lincoln (56023), Natrona (56025), Park (56029), Platte (56031), Sheridan (56033), Sublette (56035), Sweetwater (56037), Uinta (56041), Washakie (56043)*, Weston (56045)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
10 Clarks Fork Yellowstone (10070006)+, Little Wind (10080002)+, Upper Bighorn (10080007)+, Nowood (10080008)+, North Fork Shoshone (10080012)+, South Fork Shoshone (10080013)+*, Little Bighorn (10080016)+, Upper Tongue (10090101)+, Middle Fork Powder (10090201)+, Clear (10090206)+, Angostura Reservoir (10120106)+, Beaver (10120107)+, Hat (10120108)+, Middle Cheyenne-Spring (10120109)+, Rapid (10120110)+*, Middle Cheyenne-Elk (10120111)+*, Upper Belle Fourche (10120201)+, Redwater (10120203)+, Upper White (10140201)+, Snake (10150005)+, Upper North Platte (10180002)+, Pathfinder-Seminoe Reservoirs (10180003)+, Little Medicine Bow (10180005)+, Middle North Platte-Casper (10180007)+, Glendo Reservoir (10180008)+, Upper Laramie (10180010)+, Lower Laramie (10180011)+, Cache La Poudre (10190007)+, Lone Tree-Owl (10190008)+, Crow (10190009)+
14 Upper Green (14040101)+, Blacks Fork (14040107)+, Muddy (14040108)+, Great Divide closed basin (14040200)+, Little Snake (14050003)+
16 Central Bear (16010102)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Reproduction Comments: Clutch size is 4-9 (usually 6-8). Incubation, by female, lasts 15.5-16 days. Nestlings are altricial. Young leave nest at 22 days (Terres 1980). Cooperative breeding has been documented in California and Arizona; breeding units consisted of 2-5 birds; helpers (mostly yearlings, and offspring or siblings of the birds they aided) were found at about 30% of all nests in northern Arizona; nests with helpers sometimes more productive than those without helpers (Sydeman et al. 1988).
Ecology Comments: Often found in association with yellow-rumped warbler, plain titmouse, or mountain chickadee. Social throughout year. Travels in small family groups after nesting season. Family groups form larger loose flocks in fall and winter. Winter groups average 5-15 individuals; forage as a flock and roost communally within group territory (Sydeman et al. 1988).
Non-Migrant: Y
Locally Migrant: N
Long Distance Migrant: N
Terrestrial Habitat(s): Forest - Conifer, Woodland - Conifer
Special Habitat Factors: Standing snag/hollow tree
Habitat Comments: Pine forest and woodland, especially ponderosa pine, less frequently pinyon-juniper (AOU 1983). At night may roost in groups in tree cavities. For the Pacific Northwest, U.S. Forest Service et al. (1993) recommended maintaining adequate numbers (around 0.6/acre) of large snags (over 15-20 inches dbh, if possible) and green tree replacements for future snags (can be left in groups to reduce blowdown), in stands of ponderosa pine. Breeding pair digs a hole in dead wood, or uses an abandoned woodpecker hole. Nest hole is usually 2.5-18 m above ground. May be limited by nest site availability. In northern Arizona, breeding density was increased from 4-19 breeding pairs per 40 ha to 9-30 pairs after nest boxes were added (Brawn and Balda 1988). See Mitchell (1988) for specifications for the construction and placement of nest boxes.
Adult Food Habits: Granivore, Invertivore
Immature Food Habits: Granivore, Invertivore
Food Comments: Feeds on insects (wasps, ants, beetles, moths, grasshoppers, etc); also eats spiders and pine seeds. Forages on outer branches and twigs as well as along tree trunks.
Adult Phenology: Diurnal
Immature Phenology: Diurnal
Length: 11 centimeters
Weight: 11 grams
Economic Attributes Not yet assessed
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Management Summary Not yet assessed
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Population/Occurrence Delineation
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Group Name: Passerines

Use Class: Breeding
Subtype(s): Foraging Area, Nest Site, Nesting Colony
Minimum Criteria for an Occurrence: Evidence of historical breeding, or current and likely recurring breeding, at a given location, minimally a reliable observation of one or more breeding pairs in appropriate habitat. Be cautious about creating EOs for observations that may represent single breeding events outside the normal breeding distribution.

Mapping Guidance: Breeding occurrences include nesting areas as well as foraging areas.

For swallows and other species that have separate nesting and foraging areas, separations are based on nest sites or nesting areas, not to locations of foraging individuals. For example, nesting areas separated by a gap larger than the separation distance are different occurrences, regardless of the foraging locations of individuals from those nesting areas. This separation procedure is appropriate because nesting areas are the critical aspect of swallow breeding occurrences, tend to be relatively stable or at least somwhat predictable in general location, and so are the basis for effective conservation; foraging areas are much more flexible and not necessarily static.

Separation Distance for Unsuitable Habitat: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Significant dispersal and associated high potential for gene flow among populations of birds separated by tens of kilometers (e.g., Moore and Dolbeer 1989), and increasing evidence that individuals leave their usual home range to engage in extrapair copulations, as well as long foraging excursions of some species, make it difficult to circumscribe occurrences on the basis of meaningful population units without occurrences becoming too large. Hence, a moderate, standardized separation distance has been adopted for songbirds and flycatchers; it should yield occurrences that are not too spatially expansive while also accounting for the likelihood of gene flow among populations within a few kilometers of each other.

Be careful not to separate a population's nesting areas and foraging areas as different occurrences; include them in the same occurrence even if they are more than 5 km apart. Mean foraging radius (from nesting area) of Brown-headed Cowbird females was 4.0 kilometers in California, 1.2 kilometers in Illinois-Missouri (Thompson 1994). Yellow-headed Blackbirds, Brewer's Blackbirds, and probably Red-winged Blackbirds all forage up to 1.6 kilometers away from breeding colony (Willson 1966, Horn 1968). In one study, Brewer's Blackbirds were found as far as 10 kilometers from nesting area (Williams 1952), but this may be unusual.

For swallows and other parrerines with similar behavioral ecology, separation distance pertains to nest sites or nesting colonies, not to locations of foraging individuals. For example, nesting areas separated by a gap of more than 5 km are different occurrences, regardless of the foraging locations of individuals from those nesting areas. This separation procedure is appropriate because nesting areas are the critical aspect of swallow breeding occurrences, tend to be relatively stable or at least somwhat predictable in general location, and so are the basis for effective conservation; foraging areas are much more flexible and not necessarily static.

Be cautious about creating EOs for observations that may represent single breeding events outside the normal breeding distribution.

Unsuitable habitat: Habitat not normally used for breeding/feeding by a particular species. For example, unsuitable habitat for grassland and shrubland birds includes forest/woodland, urban/suburban, and aquatic habitats. Most habitats would be suitable for birds with versatile foraging habits (e.g., most corvids).

Date: 10Sep2004
Author: Hammerson, G.

Use Class: Migratory stopover
Subtype(s): Foraging Area, Roost Site
Minimum Criteria for an Occurrence: For most passerines: Evidence of recurring presence of migrating individuals (including historical) and potential recurring presence at a given location; minimally a reliable observation of 25 birds in appropriate habitat.

For swallows: Evidence of recurring presence of migrating flocks (including historical) and potential recurring presence at a given location; minimally a reliable observation of 100 birds in appropriate habitat (e.g., traditional roost sites).

Occurrences should be locations where the species is resident for some time during the appropriate season; it is preferable to have observations documenting presence over at least 7 days annually.

EOs should not be described for species that are nomadic during nonbreeding season: e.g., Lark Bunting.

Be cautious about creating EOs for observations that may represent single events.

Separation Distance for Unsuitable Habitat: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Separation distance somewhat arbitrary but intended to define occurrences of managable size for conservation purposes. Occurrences defined primarily on the basis of areas supporting concentrations of birds, rather than on the basis of distinct populations.

For swallows and other species with similar behavioral ecology, the separation distance pertains to communal roost sites rather than to foraging areas; the former tend to be more stable and specific over time than the latter.

Date: 03Sep2004
Author: Hammerson, G., and S. Cannings

Use Class: Nonbreeding
Subtype(s): Foraging Area, Roost Site
Minimum Criteria for an Occurrence: Any area used traditionally in the nonbreeding season (used for populations that are not resident in a location year-round). Minimally, reliable observations of 10 or more individuals in appropriate habitat for 20 or more days at a time. For G1-G3 species, observations of fewer individuals could constitute an occurrence of conservation value. Sites used during migration should be documented under the 'migratory stopover' location use class.

Separation Distance for Unsuitable Habitat: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Separation distance is necessarily arbitrary but attempts to balance the high mobility of birds with the need for occurrences of reasonable spatial scope. Note that a population's roost sites and foraging areas are parts of the same occurrence, even if they are more than 5 km apart.

For swallows and other species with similar behavioral ecology, the separation distance pertains to communal roost sites rather than to foraging areas; the former tend to be more stable and specific over time than the latter.

Date: 03Sep2004
Author: Hammerson, G.

Use Class: Nonmigratory
Minimum Criteria for an Occurrence: Occurrences are based on evidence of historical presence, or current and likely recurring presence, at a particular location. Such evidence minimally includes collection or reliable observation and documentation of one or more individuals in or near appropriate habitat.

These occurrence specifications are used for nonmigratory populations of passerine birds.

Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Significant dispersal and associated high potential for gene flow among populations of birds separated by tens of kilometers (e.g., Moore and Dolbeer 1989), and increasing evidence that individuals leave their usual home range to engage in extrapair copulations, as well as long foraging excursions of some species, make it difficult to circumscribe occurrences on the basis of meaningful population units without occurrences becoming too large. Hence, a moderate, standardized separation distance has been adopted for songbirds and flycatchers; it should yield occurrences that are not too spatially expansive while also accounting for the likelihood of gene flow among populations within a few kilometers of each other.

Be careful not to separate a population's nesting areas and breeding-season foraging areas as different occurrences; include them in the same occurrence even if they are more than 5 km apart. Blue jays have small summer home ranges but fly up to 4 kilometers to harvest mast (Tarvin and Woolfenden 1999). Flocks of pinyon jays range over 21-29 square kilometers (Ligon 1971, Balda and Bateman 1971); nesting and foraging areas may be widely separated. Tricolored blackbirds forage in flocks that range widely to more than 15 kilometers from the nesting colony (Beedy and Hamilton 1999).

Unsuitable habitat: Habitat not normally used for breeding/feeding by a particular species. For example, unsuitable habitat for grassland and shrubland birds includes forest/woodland, urban/suburban, and aquatic habitats. Most habitats would be suitable for birds with versatile foraging habits (e.g., most corvids).

Date: 10Sep2004
Author: Hammerson, G.
Notes: These specs pertain to nonmigratory species.
Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
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Authors/Contributors
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Element Ecology & Life History Edition Date: 20Jan1994
Element Ecology & Life History Author(s): Hammerson, G.

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

References
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