Empidonax alnorum - Brewster, 1895
Alder Flycatcher
Other English Common Names: alder flycatcher
Other Common Names: Maria-Fibui, Papa-Moscas-Fibiu
Taxonomic Status: Accepted
Related ITIS Name(s): Empidonax alnorum Brewster, 1895 (TSN 178340)
French Common Names: moucherolle des aulnes
Spanish Common Names: Mosquero Ailero, Mosqueta Boreal
Unique Identifier: ELEMENT_GLOBAL.2.104821
Element Code: ABPAE33030
Informal Taxonomy: Animals, Vertebrates - Birds - Perching Birds
Image 10974

© Jeff Nadler

 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Aves Passeriformes Tyrannidae Empidonax
Genus Size: C - Small genus (6-20 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: Empidonax alnorum
Taxonomic Comments: Formerly regarded as a single species, E. traillii (Traill's Flycatcher), conspecific withE. traillii (Willow Flycatcher) (AOU 1983, 1998).
Conservation Status
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NatureServe Status

Global Status: G5
Global Status Last Reviewed: 07Apr2016
Global Status Last Changed: 02Dec1996
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Nation: United States
National Status: N5B (19Mar1997)
Nation: Canada
National Status: N5B,N5M (26Jan2018)

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 Alabama (SNA), Alaska (S5B), Arkansas (SNA), Colorado (SNA), Connecticut (S3B), Delaware (SNA), District of Columbia (S1N), Florida (SNA), Georgia (SNRN), Illinois (S2), Indiana (S2B), Iowa (S3N), Kansas (SNA), Kentucky (SNA), Louisiana (SNA), Maine (S4S5B), Maryland (S2B), Massachusetts (S4B), Michigan (S5), Minnesota (SNRB), Mississippi (SNA), Missouri (SNA), Montana (S3B), Nebraska (SNRN), New Hampshire (S5B), New Jersey (S4B), New York (S5B), North Carolina (S2B), North Dakota (SU), Ohio (S3), Oklahoma (S2N), Pennsylvania (S3S4B), South Carolina (SNA), South Dakota (SNA), Tennessee (S1), Texas (S4), Vermont (S5B), Virginia (S1S2B), West Virginia (S3B), Wisconsin (S4B)
Canada Alberta (S5B), British Columbia (S5B), Labrador (S4B,SUM), Manitoba (S5B), New Brunswick (S5B,S5M), Newfoundland Island (S4B,SUM), Northwest Territories (S4B), Nova Scotia (S5B), Nunavut (SUB,SUM), Ontario (S5B), Prince Edward Island (S5B), Quebec (S5B), Saskatchewan (S5B,S5M), Yukon Territory (S5B)

Other Statuses

IUCN Red List Category: LC - Least concern

NatureServe Global Conservation Status Factors

Range Extent Comments: BREEDING: central Alaska and Yukon east across central Canada to southern Labrador and Newfoundland, south to southern British Columbia, northern North Dakota, Great Lakes region, Pennsylvania, southeastern New York, and northern Massachusetts; in Appalachians to southwestern Virginia, northeastern Tennessee, and northwestern North Carolina (Lowther 1999). NON-BREEDING: East base of Andes from central Colombia to Bolivia; possibly northern Argentina (Stiles and Skutch 1989, Lowther 1999).

Short-term Trend Comments: North American Breeding Bird Survey data indicate a significant population increase in North America between 1966 and 1989 (Droege and Sauer 1990).

Other NatureServe Conservation Status Information

Distribution
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Global Range: BREEDING: central Alaska and Yukon east across central Canada to southern Labrador and Newfoundland, south to southern British Columbia, northern North Dakota, Great Lakes region, Pennsylvania, southeastern New York, and northern Massachusetts; in Appalachians to southwestern Virginia, northeastern Tennessee, and northwestern North Carolina (Lowther 1999). NON-BREEDING: East base of Andes from central Colombia to Bolivia; possibly northern Argentina (Stiles and Skutch 1989, Lowther 1999).

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 AK, AL, AR, CO, CT, DC, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NY, OH, OK, PA, SC, SD, TN, TX, VA, VT, WI, WV
Canada AB, BC, LB, MB, NB, NF, NS, NT, NU, ON, PE, QC, SK, YT

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)
CT Hartford (09003), Litchfield (09005), Middlesex (09007), New London (09011)
IN Elkhart (18039), Kosciusko (18085), La Porte (18091), Lagrange (18087), Porter (18127), St. Joseph (18141), Steuben (18151)
MD Allegany (24001), Baltimore County (24005), Garrett (24023), Harford (24025)*, Montgomery (24031)*
MT Teton (30099)
NC Alleghany (37005), Ashe (37009), Avery (37011), Buncombe (37021), Haywood (37087), Jackson (37099), Mitchell (37121), Transylvania (37175), Watauga (37189), Yancey (37199)
ND Cavalier (38019)
NJ Sussex (34037)
TN Carter (47019), Johnson (47091)
VA Augusta (51015), Bland (51021)*, Grayson (51077), Highland (51091), Scott (51169), Smyth (51173), Tazewell (51185), Wise (51195)
WV Tucker (54093)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
01 Lower Connecticut (01080205)+, Farmington (01080207)+, Thames (01100003)+, Housatonic (01100005)+
02 Rondout (02020007)+, Lower Susquehanna (02050306)+, Gunpowder-Patapsco (02060003)+, South Branch Potomac (02070001)+, North Branch Potomac (02070002)+, South Fork Shenandoah (02070005)+, Middle Potomac-Catoctin (02070008)+*
04 Little Calumet-Galien (04040001)+, St. Joseph (04050001)+
05 Cheat (05020004)+, Youghiogheny (05020006)+, Upper New (05050001)+, Middle New (05050002)+*, Tippecanoe (05120106)+
06 North Fork Holston (06010101)+*, South Fork Holston (06010102)+, Watauga (06010103)+, Upper French Broad (06010105)+, Pigeon (06010106)+, Nolichucky (06010108)+, Tuckasegee (06010203)+, Upper Clinch (06010205)+
07 Kankakee (07120001)+
09 Lower Pembina River (09020316)+
10 Teton (10030205)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Basic Description: A small bird (flycatcher).
Reproduction Comments: Clutch size is 3-4. Incubation, by female, lasts 12-14 days. Young leave nest at 13-14 days.
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: Y
Mobility and Migration Comments: Arrives in North American nesting areas generally in May-June (Terres 1980). Migrates through Costa Rica in definite waves, late August-early November and March-late May (Stiles and Skutch 1989). Arrives in southeastern Peru in mid- to late October (Keast and Morton 1980).
Palustrine Habitat(s): Bog/fen, FORESTED WETLAND, Riparian, SCRUB-SHRUB WETLAND
Terrestrial Habitat(s): Old field, Shrubland/chaparral
Habitat Comments: Brushy and scrubby growth, thickets, deciduous forest edge, open second growth, and swamps. Nonbreeding: also woodland, but migrants seldom enter tall shady second growth or woodland (Stiles and Skutch 1989). Nests in damp thickets of alder and various shrubs, in bogs, along marshy borders of lakes, and in brush along stream banks, less than 2 m above ground (Harrison 1979).
Adult Food Habits: Invertivore
Immature Food Habits: Invertivore
Food Comments: Eats mainly insects obtained by flycatching (Bent 1942) or from vegetation; also eats some berries (Stiles and Skutch 1989).
Adult Phenology: Diurnal
Immature Phenology: Diurnal
Length: 15 centimeters
Weight: 14 grams
Economic Attributes Not yet assessed
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Management Summary Not yet assessed
Help
Population/Occurrence Delineation
Help
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: 13Jan1995
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
Help
  • Alabama Ornithological Society. 2006. Field checklist of Alabama birds. Alabama Ornithological Society, Dauphin Island, Alabama. [Available online at http://www.aosbirds.org/documents/AOSChecklist_april2006.pdf ]

  • Allen, C. R., S. Demarais, and R. S. Lutz. 1994. Red imported fire ant impact on wildlife: an overview. The Texas Journal of Science 46(1):51-59.

  • American Ornithologists Union (AOU). 1998. Check-list of North American Birds. 7th edition. American Ornithologists Union, Washington, D.C. 829 pages.

  • American Ornithologists' Union (AOU). 1983. Check-list of North American Birds, 6th edition. Allen Press, Inc., Lawrence, Kansas. 877 pp.

  • 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/.

  • Andrews, R. R. and R. R. Righter. 1992. Colorado Birds. Denver Museum of Natural History, Denver. 442 pp.

  • Aquin, P. 1999. Évaluation de la situation des groupes taxonomiques des oiseaux du Québec. Ministère de l'Environnement et de la Faune. 13 pages.

  • B83COM01NAUS - Added from 2005 data exchange with Alberta, Canada.

  • Balda, R. P., and G. C. Bateman. 1971. Flocking and annual cycle of the piñon jay, Gymnorhinus cyanocephalus. Condor 73:287-302.

  • Bent, A.C. 1942. Life histories of North American flycatchers, larks, swallows, and their allies. U.S. National Museum Bulletin 179. Washington, DC.

  • Bierly, M.L. 1980. Bird Finding in Tennessee. 3825 Bed- ford Ave., Nashville, TN 37125.

  • BirdLife International. 2004b. Threatened birds of the world 2004. CD ROM. BirdLife International, Cambridge, UK.

  • Bull, John. 1974. Birds of New York State. Doubleday, Garden City, New York. 655 pp.

  • Campbell, R.W., N.K. Dawe, I. McTaggart-Cowan, J.M. Cooper, G.W. Kaiser, M.C.E. McNall and G.E.J. Smith 1997. The Birds of British Columbia, Vol. 3, Passerines: Flycatchers through Vireos. UBC Press in cooperation with Environ. Can., Can. Wildl. Serv. and B.C. Minist. Environ., Lands and Parks, Wildl. Branch. 700pp.

  • DICKINSON, MARY B., ED. 1999. FIELD GUIDE TO THE BIRDS OF NORTH AMERICA, 3RD ED. NATIONAL GEOGRAPHIC SOCIETY, WASHINGTON, D.C. 480 PP.

  • Desrosiers A., F. Caron et R. Ouellet. 1995. Liste de la faune vertébrée du Québec. Les publications du Québec. 122

  • Dionne C. 1906. Les oiseaux de la province de Québec. Dussault et Proulx.

  • Droege, S., and J.R. Sauer. 1990. North American Breeding Bird Survey, annual summary, 1989. U.S. Fish and Wildlife Service, Biological Report 90(8). 22 pp.

  • Dunn, E. H., C. M. Downes, and B. T. Collins. 2000. The Canadian Breeding Bird Survey, 1967-1998. Canadian Wildlife Service Progress Notes No. 216. 40 pp.

  • Erskine, A. J. 1992. Atlas of breeding birds of the Maritime Provinces. Nimbus Publishing and the Nova Scotia Museum, Halifax, Nova Scotia.

  • Godfrey, W. E. 1986. The birds of Canada. Revised edition. National Museum of Natural Sciences, Ottawa. 596 pp. + plates.

  • Gorski, L. G. 1969. Systematics and ecology of sibling species of Traills Flycatcher. Ph. D. dissertation, University of Connecticut, Storrs, Connecticut.

  • Gorski, L.G. 1971. Traills Flycatchers of the fee-bee-o songform wintering in Peru. Auk 88:429-431.

  • Harrison, C. 1978. A Field Guide to the Nests, Eggs and Nestlings of North American Birds. Collins, Cleveland, Ohio.

  • Harrison, H. H. 1979. A field guide to western birds' nests. Houghton Mifflin Company, Boston. 279 pp.

  • Horn, H. S. 1968. The adaptive significance of colonial nesting in the Brewer's Blackbird. Ecology 49:682-694.

  • Howell, S. N. G., and S. Webb. 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press, Oxford, UK.

  • Imhof, T. A. 1976. Alabama birds. Second edition. University of Alabama Press, Tuscaloosa. 445 pages.

  • Johnsgard, P. A. 1986. Birds of the Rocky Mountains with particular reference to national parks in the Northern Rocky Mountain region. Colorado Associated University Press, Boulder. xi + 504 pp.

  • Keast, A., and E.S. Morton. 1980. Migrant birds in the neotropics: ecology, distribution, and conservation. Smithsonian Institution Press, Washington, DC.

  • Ligon, J. D. 1971. Late summer-autumnal breeding of the piñon jay in New Mexico. Condor 73:147-153.

  • Lowery, George H. 1974. The Birds of Louisiana. LSU Press. 651pp.

  • Lowther, P.E. 1999. Alder Flycatcher (EMPIDONAX ALNORUM). In A. Poole and F. Gill, editors, The Birds of North America, No. 446. The Birds of North America, Inc., Philadelphia, PA. 20 pp.

  • Lowther, P.E. 1999. Alder Flycatcher. The Birds of North America. Vol. 12, No. 446: American Orinithologists' Union. The Academy of Natural Sciences of Philadelphia.

  • Mirarchi, R.E., editor. 2004. Alabama Wildlife. Volume 1. A checklist of vertebrates and selected invertebrates: aquatic mollusks, fishes, amphibians, reptiles, birds, and mammals. The University of Alabama Press, Tuscaloosa, Alabama. 209 pages.

  • Montana Bird Distribution Online Database. 2001. Helena, Montana, USA. April-September 2003. http://nhp.nris.state.mt.us/mbd/.

  • Moore, W. S., and R. A. Dolbeer. 1989. The use of banding recovery data to estimate dispersal rates and gene flow in avian species: case studies in the Red-winged Blackbird and Common Grackle. Condor 91:242-253.

  • Mount, R. H., editor. 1986. Vertebrate animals of Alabama in need of special attention. Alabama Agricultural Experiment Station, Auburn University, Alabama. 124 pages.

  • New York State Breeding Bird Atlas. 1984. Preliminary species distribution maps, 1980-1984. New York State Department of Environmental Conservation, Wildlife Resources Center. Delmar, NY.

  • New York State Department of Environmental Conservation. Checklist of the amphibians, reptiles, birds, and mammals of New York State, including their protective status. Nongame Unit, Wildlife Resources Center, Delmar, NY.

  • Nicholson, C.P. 1997. Atlas of the breeding birds of Tennessee. The University of Tennessee Press. 426 pp.

  • Ouellet H., M. Gosselin et J.P. Artigau. 1990. Nomenclature française des oiseaux d'Amérique du Nord. Secrétariat d'État du Canada. 457 p.

  • Parker III, T. A., D. F. Stotz, and J. W. Fitzpatrick. 1996. Ecological and distributional databases for neotropical birds. The University of Chicago Press, Chicago.

  • Parks Canada. 2000. Vertebrate Species Database. Ecosystems Branch, 25 Eddy St., Hull, PQ, K1A 0M5.

  • Peterjohn, B. J., J. R. Sauer, and S. Orsillo. 1995. Breeding bird survey: population trends 1966-1992. Pages 14-21 in E. T. LaRoe, G. S. Farris, C. E. Puckett, P. D. Doran, and M. J. Mac, editors. Our Living Resources. National Biological Service, Washington, D.C.

  • Ridgely, R. S. 2002. Distribution maps of South American birds. Unpublished.

  • Ridgely, R. S. and J. A. Gwynne, Jr. 1989. A Guide to the Birds of Panama. 2nd edition. Princeton University Press, Princeton, USA.

  • Sedgwick, J. A. 2000. Willow Flycatcher (Empidonax traillii). In The Birds of North America. No. 533 (A. Poole and F. Gill, eds.). The Birds of North America, Inc. Philadelphia, Pennsylvania.

  • Sibley, D. A. 2000a. The Sibley guide to birds. Alfred A. Knopf, New York.

  • Spahn, R. 1987. Highlights of the spring season. Kingbird 37(3):133-142.

  • Stiles, F. G. and A. F. Skutch. 1989. A guide to the birds of Costa Rica. Cornell University Press, Ithaca, New York, USA. 511 pp.

  • Tarvin, K. A., and G. E. Woolfenden. 1999. Blue Jay (Cyanocitta cristata). No. 469 IN A. Poole and F. Gill, editors. The birds of North America. The Birds of North America, Inc., Philadelphia, PA. 32pp.

  • Terres, J. K. 1980. The Audubon Society encyclopedia of North American birds. Alfred A. Knopf, New York.

  • Thompson, F. R., III. 1994. Temporal and spatial patterns of breeding brown-headed cowbirds in the midwestern United States. Auk 111:979-990.

  • Williams, L. 1952b. Breeding behavior of the Brewer blackbird. Condor 54:3-47.

  • Willson, M. F. 1966. Breeding ecology of the Yellow-headed Blackbird. Ecological Monographs 36:51-77.

  • Winkler, K. 1994. Divergence in the mitochondrial DNA of EMPIDONAX TRAILLII and E. ALNORUM, with notes on hybridization. Auk 111:710-713.

  • Zook, J. L. 2002. Distribution maps of the birds of Nicaragua, Costa Rica, and Panama. Unpublished.

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Citation for data on website including State Distribution, Watershed, and Reptile Range maps:
NatureServe. 2018. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed:

Citation for Bird Range Maps of North America:
Ridgely, R.S., T.F. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, B.E. Young, and J.R. Zook. 2003. Digital Distribution Maps of the Birds of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Bird Range Maps of North America:
"Data provided by NatureServe in collaboration with Robert Ridgely, James Zook, The Nature Conservancy - Migratory Bird Program, Conservation International - CABS, World Wildlife Fund - US, and Environment Canada - WILDSPACE."

Citation for Mammal Range Maps of North America:
Patterson, B.D., G. Ceballos, W. Sechrest, M.F. Tognelli, T. Brooks, L. Luna, P. Ortega, I. Salazar, and B.E. Young. 2003. Digital Distribution Maps of the Mammals of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Mammal Range Maps of North America:
"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:
http://www.natureserve.org/library/birdDistributionmapsmetadatav1.pdf.

Full metadata for the Mammal Range Maps of North America is available at:
http://www.natureserve.org/library/mammalsDistributionmetadatav1.pdf.

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