Spatula discors - (Linnaeus, 1766)
Blue-winged Teal
Other English Common Names: blue-winged teal
Other Common Names: Marreca-Sará
Synonym(s): Anas discors Linnaeus, 1766
Taxonomic Status: Accepted
Related ITIS Name(s): Anas discors Linnaeus, 1766 (TSN 175086)
French Common Names: sarcelle à ailes bleues
Spanish Common Names: Cerceta Ala Azul, Pato Media Luna, Pato de Alas Az
Unique Identifier: ELEMENT_GLOBAL.2.106246
Element Code: ABNJB10130
Informal Taxonomy: Animals, Vertebrates - Birds - Waterfowl
Image 11090

© Jeff Nadler

 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Aves Anseriformes Anatidae Spatula
Check this box to expand all report sections:
Concept Reference
Help
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: Anas discors
Taxonomic Comments: May hybridize in the wild with A. cyanoptera (AOU 1983). Formerly (AOU 1983, 1998) considered part of Anas, but now treated as separate on the basis of genetic data (Gonzalez et al. 2009) which indicate that Anas as previously constituted was paraphyletic, and further that it consisted of four deeply divergent clades, now recognized as the separate genera Sibirionetta, Spatula, Mareca, and Anas (cf. Livezey 1991). Linear sequence of genera and species follows Gonzalez et al. (2009). (AOU 2017).
Conservation Status
Help

NatureServe Status

Global Status: G5
Global Status Last Reviewed: 06Apr2016
Global Status Last Changed: 21Nov1996
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Nation: United States
National Status: N5B,N5N (05Jan1997)
Nation: Canada
National Status: N5B,N5M (29Jan2018)

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 (S2B,S4N), Alaska (S4B), Arizona (S2B,S5N), Arkansas (S2B,S5N), California (SNRB,SNRN), Colorado (S5B), Connecticut (SHB), Delaware (S3B), District of Columbia (S2N), Florida (SNRN), Georgia (S5), Idaho (S2B), Illinois (S3), Indiana (S4B), Iowa (S4B,S5N), Kansas (S3B), Kentucky (S1S2B), Louisiana (S4B,S5N), Maine (S4S5B), Maryland (S2B,S3S4N), Massachusetts (S2B,S5M), Michigan (S3), Minnesota (SNRB), Mississippi (S4N), Missouri (SNRB,SNRM), Montana (S5B), Navajo Nation (S1N), Nebraska (S5), Nevada (S2), New Hampshire (S3B), New Jersey (S5), New Mexico (S3B,S4N), New York (S2S3B,SNRN), North Carolina (SHB,S2N), North Dakota (SNRB), Ohio (S3), Oklahoma (S4S5), Oregon (S4), Pennsylvania (S3B), Rhode Island (S1B), South Carolina (SNRB,SNRN), South Dakota (S5B), Tennessee (S2B), Texas (S3B,S5N), Utah (S3B), Vermont (S2B), Virginia (S1B,S2N), Washington (S5B), West Virginia (S1B), Wisconsin (S3S4B), Wyoming (S4N,S5B)
Canada Alberta (S5B), British Columbia (S4S5B), Labrador (S2M), Manitoba (S5B), New Brunswick (S4B,S4M), Newfoundland Island (SUB,S1M), Northwest Territories (S4B), Nova Scotia (S3S4B), Nunavut (SUB,SUM), Ontario (S4), Prince Edward Island (S3B), Quebec (S3S4B), Saskatchewan (S5B,S5M), Yukon Territory (S4B)

Other Statuses

IUCN Red List Category: LC - Least concern

NatureServe Global Conservation Status Factors

Range Extent: >2,500,000 square km (greater than 1,000,000 square miles)
Range Extent Comments: BREEDS: southern Canada south to southern California, New Mexico, central Texas, Louisiana, and North Carolina; also recently in Hawaii (Aimakapa Pond, Hawaii). Breeding abundance is highest in the prairie pothole region of the north-central U.S. and south-central Canada. NORTHERN WINTER: southern U.S. south to southern Peru, central Argentina, and southern Brazil (mainly to nothern South America); the most common and widespread migrant duck in Colombia and Costa Rica); common in Puerto Rico and the Virgin Islands; regular in recent years in Hawaii. Major wintering concentrations occur along the Gulf Coast of Mexico and in Caribbean coastal areas of Venezuela, Colombia, and Guyana (Gammonley and Fredrickson 1995). In the U.S., the highest winter densities occur in southern Texas and peninsular Florida (Root 1988).

Population Size: >1,000,000 individuals
Population Size Comments: Breeding population estimates, subject to considerable bias and error, ranged between 2.7 million and 5.8 million between 1955 and 1990, with no clear long-term trend (Gammonley and Fredrickson 1995). The May 1996 breeding population survey yielded an estimate of 6.4 million birds, greater than the 1995 estimate of 5.1 million and 53% above the long-term average (USFWS 1996).

Short-term Trend: Relatively Stable (<=10% change)

Other NatureServe Conservation Status Information

Protection Needs: Minimize loss and degradation of wetlands in winter range.

Distribution
Help
Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) BREEDS: southern Canada south to southern California, New Mexico, central Texas, Louisiana, and North Carolina; also recently in Hawaii (Aimakapa Pond, Hawaii). Breeding abundance is highest in the prairie pothole region of the north-central U.S. and south-central Canada. NORTHERN WINTER: southern U.S. south to southern Peru, central Argentina, and southern Brazil (mainly to nothern South America); the most common and widespread migrant duck in Colombia and Costa Rica); common in Puerto Rico and the Virgin Islands; regular in recent years in Hawaii. Major wintering concentrations occur along the Gulf Coast of Mexico and in Caribbean coastal areas of Venezuela, Colombia, and Guyana (Gammonley and Fredrickson 1995). In the U.S., the highest winter densities occur in southern Texas and peninsular Florida (Root 1988).

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, AZ, CA, CO, CT, DC, DE, FL, GA, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NN, NV, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY
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 2005; 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)*, Windham (09015)*
ID Ada (16001), Bear Lake (16007), Bingham (16011), Blaine (16013), Bonner (16017), Boundary (16021), Camas (16025), Canyon (16027), Custer (16037), Fremont (16043), Jefferson (16051), Kootenai (16055), Lincoln (16063), Nez Perce (16069)
KY Caldwell (21033), Christian (21047), Fulton (21075), Hardin (21093), Jefferson (21111)*, Jessamine (21113), Simpson (21213), Trigg (21221), Union (21225), Warren (21227)
RI Newport (44005)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
01 Lower Connecticut (01080205)+*, Cape Cod (01090002)+, Quinebaug (01100001)+*, Housatonic (01100005)+*
05 Lower Kentucky (05100205)+, Upper Green (05110001)+, Barren (05110002)+, Lower Cumberland (05130205)+, Red (05130206)+, Silver-Little Kentucky (05140101)+*, Highland-Pigeon (05140202)+
08 Obion (08010202)+
16 Bear Lake (16010201)+
17 Lower Kootenai (17010104)+, Pend Oreille Lake (17010214)+, Coeur D'alene Lake (17010303)+, Upper Spokane (17010305)+, Idaho Falls (17040201)+, Upper Henrys (17040202)+, American Falls (17040206)+, Lake Walcott (17040209)+, Beaver-Camas (17040214)+, Camas (17040220)+, Little Wood (17040221)+, Lower Boise (17050114)+, Middle Snake-Payette (17050115)+, Upper Salmon (17060201)+, Clearwater (17060306)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
Help
Reproduction Comments: Nesting begins in late April in the Midwest. Peak nesting occurs usually in late May in the U.S., in early June in Canada (Gammonley and Fredrickson 1995). Clutch size 6-15 (usually 9-11). Incubation 23-27 days, by female. Nestlings precocial, tended by female. First flight of young occurs 35-44 days after hatching (Terres 1980). First breeds at one year; most yearling females nest. Renesting is likely if nest loss occurs early in laying period and/or when wetland conditions are good (Gammonley and Fredrickson 1995).
Ecology Comments: Nonbreeding: usually in flocks. A few weeks after incubation begins, males form molting flocks in or away from breeding areas. May feed with other dabbling ducks, coots, and shorebirds. The size of local breeding populations varies annually in response to habitat conditions. Has the highest annual mortality rate (reaching 65%) of all the dabbling ducks; this probably is due to hunting and the long over-ocean migration that most individuals experience. Large numbers of nests are lost to mammalian and avian predators. Most post-hatching mortality occurs in the first two weeks. Annual survival rate is somwehat over 50% in adults and 32-44% in juveniles (Gammonley and Fredrickson 1995).
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: Y
Mobility and Migration Comments: Migrates north to breeding areas in late northern spring. Arrives in prairie breeding areas mainly in late April and May. Southward migration is relatively early. Begins to migrate south in August-September (Terres 1980), with males generally preceding females and immatures; most are gone from the upper Midwest by early October. Present in South America from early September to late April, rarely to early June (Hilty and Brown 1986). Arrives in Costa Rica September-October, departs by end of April or May (Stiles and Skutch 1989). Those wintering in South America begin moving northward through Mexico in January (Gammonley and Fredrickson 1995). Migrates usually in conspecific flocks.
Estuarine Habitat(s): Herbaceous wetland, Lagoon, River mouth/tidal river, Tidal flat/shore
Riverine Habitat(s): Low gradient
Lacustrine Habitat(s): Shallow water
Palustrine Habitat(s): HERBACEOUS WETLAND, Riparian
Terrestrial Habitat(s): Cropland/hedgerow, Grassland/herbaceous
Habitat Comments: Marshes, ponds, sloughs, lakes, and sluggish streams. In migration and when not breeding, in both freshwater and brackish situations (AOU 1983); prefers freshwater marshes, ponds, and sloughs, but occurs also in river pools, salt ponds, coastal lagoons, estuaries, and flooded pastures (Costa Rica, Stiles and Skutch 1989; Gammonley and Fredrickson 1995). Commonly colonizes newly available habitats.

Optimal nesting habitats include semi-permanent wetlands, ponds, and seasonal wetlands surrounded by grassland (Brewer et al. 1991). Nests usually on the ground among tall grasses or sedges, usually near water; seems to prefer to nest in native grass comunities in good range condition (Gammonley and Fredrickson 1995). Nest cover is provided by matted residual herbaceous vegetation (Gammonley and Fredrickson 1995). In the Midwest, bluegrass is the preferred nesting cover; also commonly uses hayfields and sedge meadows within 100 m of water (Brewer et al. 1991). Broods often use semi-permanent wetlands that include about 50% open water and a good supply of aquatic insects and other invertebrates (Brewer et al. 1991). Stock ponds with well-developed emergent vegetation provide locally important brood habitat (Gammonley and Fredrickson 1995). Females change breeding sites from year to year in response to changes in wetland condtitions (Gammonley and Fredrickson 1995). Male breeding territories include one or two small ponds within the home range (Gammonley and Fredrickson 1995).

Adult Food Habits: Herbivore, Invertivore
Immature Food Habits: Herbivore, Invertivore
Food Comments: Omnivorous; feeds mainly in shallowly flooded wetlands. Feeds on vegetative parts of aquatic plants (algae, duckweeds, pondweeds, etc.) as well as seeds (sedges, pondweeds, grasses, etc.). Also consumes large amounts of aquatic invertebrates, which are especially important in the breeding season and in the diet of the young. See Gammonley and Fredrickson (1995) for further details.
Adult Phenology: Diurnal
Immature Phenology: Diurnal
Phenology Comments: Broods are more active and more easily observed in early morning and late afternoon (Gammonley and Fredrickson 1995). Molting males, flightless for about a month, tend to feed at night.
Length: 39 centimeters
Weight: 409 grams
Economic Attributes
Help
Economic Comments: Hunted especially during special early seasons, with the greatest harvest in the Mississippi and Central flyways; harvest rate south of the U.S. is poorly known, but probably at least 21% of the total harvest occurs there (Gammonley and Fredrickson 1995).
Management Summary
Help
Management Requirements: Restoration of temporary and seasonal wetlands is particularly needed in agricultural landscapes (Gammonley and Fredrickson 1995). Maintenance of optimal nesting habitat may require active management (allowing dead vegetation to accumulate; periodic burning, mowing, or grazing to prevent it from becoming too dense); disturbance should be performed after the peak hatching period; seeded dense nesting cover used by mallards and gadwalls seems to be less attractive to blue-winged teal (Gammonley and Fredrickson 1995).

See Barker et al. (1990) for information on the effects of different livestock grazing systems on nesting success in North Dakota.

See Marcy (1986) for specifications for the construction and placement of wire nest baskets.

Population/Occurrence Delineation
Help
Group Name: Dabbling Ducks

Use Class: Breeding
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.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 10 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Separation distance a compromise between three times average home range diameters (about 5-6 kilometers), and the great mobility of these birds. Home ranges: female Black Duck, mean 130 hectares during prelaying and laying period (n = 7, Ringelman et al. 1982); Mallards, mean 283 hectares (Dzubin 1955), 210 hectares (females) and 240 hectares (males) (Gilmer et al. 1975).
Breeding site fidelity: female Black Ducks in New England, 25% returned to nest in the following year, most within 91 meters of previous nest (Coulter and Miller 1968).

Inferred Minimum Extent of Habitat Use (when actual extent is unknown): 1.6 km
Inferred Minimum Extent Justification: Diameter of average home range of Mallards (Gilmer et al. 1975).
Date: 08Mar2001
Author: Cannings, S.

Use Class: Migratory stopover
Subtype(s): Staging area, Foraging area, Roosting area
Minimum Criteria for an Occurrence: Evidence of recurring presence of migrating or staging flocks (including historical); and potential recurring presence at a given location, minimally a reliable observation of 25 birds/0.5 square kilometer in appropriate habitat. 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. Be cautious about creating EOs for observations that may represent single events.
Separation Distance for Unsuitable Habitat: 10 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Separation distance somewhat arbitrary; set at 10 kilometers to define occurrences of managable size for conservation purposes. Occurrences defined primarily on the basis of areas supporting concentrations of foraging birds, rather than on the basis of distinct populations.
Date: 11Apr2002
Author: Cannings, S.

Use Class: Nonbreeding
Subtype(s): Molting area, Wintering area, Non-breeding feeding concentration area, Roosting area
Minimum Criteria for an Occurrence: Evidence of recurring presence of molting or wintering flocks (including historical); and potential recurring presence at a given location, minimally a reliable observation of 25 birds/0.5 square kilometer in appropriate habitat. 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 20 days annually. Be cautious about creating EOs for observations that may represent single events.
Mapping Guidance: Map roosting and feeding areas with separate polygons in same EO.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 10 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Separation distance somewhat arbitrary; set at 10 kilometers to define occurrences of managable size for conservation purposes. Wintering flocks of American Black Ducks fly an average of 10 kilometres from roost to foraging area, but have been recorded flying up to 43 kilometres (Frazer et al. 1990). However, occurrences defined primarily on the basis of areas supporting concentrations of foraging birds, rather than on the basis of distinct populations.
Date: 29May2001
Author: Cannings, S.
Population/Occurrence Viability
Help
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
Help
Authors/Contributors
Help
Element Ecology & Life History Edition Date: 31Aug1995
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 ]

  • American Ornithological Society (AOS). Chesser, R. T., K. J. Burns, C. Cicero, J. L. Dunn, A. W. Kratter, I. J. Lovette, P. C. Rasmussen, J. V. Remsen, Jr., J. D. Rising, D. F. Stotz, and K. Winker. 2017. Fifty-eighth supplement to the American Ornithological Society's Check-list of North American Birds. The Auk: Ornithological Advances 134:751-773. DOI: 10.1642/AUK-17-72.1.

  • 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/.

  • American Ornithologists' Union (AOU). Chesser, R.T., K.J. Burns, C. Cicero, J.L. Dunn, A.W. Kratter, I.J. Lovette, P.C. Rasmussen, J.V. Remsen, Jr., J.D. Rising, D.F. Stotz, and K. Winker. 2017. Fifty-eighth Supplement to the American Ornithologists' Union Check-list of North American Birds. The Auk 134:751-773.

  • 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.

  • BUCKELEW, A. AND G. HALL. 1994. WV BREEDING BIRD ATLAS. UNIVERSITY OF PITTSBURGH PRESS.

  • Barbour, R.W. et al. 1973. Kentucky Birds.

  • Barker, W. T., et al. 1990. Effects of specialized grazing systems on waterfowl production in southcentral North Dakota. Trans. 55th North American Wildl. & Nat. Res. Conf., pp. 462-474.

  • Bellrose, F.C. 1976. Ducks, geese and swans of North America. Stackpole Books, Harrisburg, PA.

  • Bennett, L.J. 1938. The blue-winged teal: its ecology and management. Ames, Iowa. 144pp.

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

  • Braun, M. J., D. W. Finch, M. B. Robbins, and B. K. Schmidt. 2000. A field checklist of the birds of Guyana. Smithsonian Institution, Washington, D.C.

  • Brewer, R., G.A. McPeek, and R.J. Adams, Jr. 1991. The Atlas of Breeding Birds of Michigan. Michigan State University Press, East Lansing, Michigan. xvii + 594 pp.

  • Campbell, R.W., N.K. Dawe, I.McT. Cowan, J.M. Cooper, G. Kaiser, and M.C.E. McNall. 1990. The Birds of British Columbia, Vol. 1. Nonpasserines: Introduction, Loons through Waterfowl. Royal B.C. Mus. in association with Environ. Can., Can. Wildl. Serv. 514pp.

  • Canadian Wildlife Service. 1995. Last Mountain Lake and Stalwart National Wildlife Areas: Bird Checklist - Fourth Edition. Environment Canada. Ottawa, ON.

  • Canadian Wildlife Service. 1996. Population status and trends in waterfowl in Canada. Bird Trends (Canadian Wildlife Service) 5: 1-7.

  • Castro, I. and A. Phillips. 1996. A guide to the birds of the Galapagos Islands. Princeton University Press, Princeton, New Jersey, USA.

  • Coulter, M. W., and W. R. Miller. 1968. Nesting biology of Black Ducks and Mallards in northern New England. Vermont Fish and Game Department Bulletin 68-2.

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

  • DIVISION OF NATURAL RESOURCES. 1994. HUNTING AND TRAPPING REGULATIONS. WV DIVISION OF NATURAL RESOURCES, CHARLESTON, WV.

  • 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.

  • Downes, C.M., and B.T. Collins. 2007. Canadian Bird Trends Web site Version 2.2. Canadian Wildlife Service, Environment Canada, Gatineau, Quebec, K1A 0H3.

  • 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.

  • Dzubin, A. 1955. Some evidence of home range in waterfowl. Transactions of the North American Wildlife Conference 20:278-298.

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

  • Frazer, C., J. R. Longcore, and D. G. McAuley. 1990a. Habitat use by postfledging American black ducks in Maine and New Brunswick. Journal of Wildlife Management 54:451-459.

  • Gammonley, J. H., and L. H. Fredrickson. 1995. Life history and management of the blue-winged teal. USDI National Biological Service, Waterfowl Management Handbook 13.1.8. 7 pp.

  • Gilmer, D. S., I. J. Ball, L. M. Cowardin, J. H. Riechmann, and J. R. Tester. 1975. Habitat use and home range of mallards breeding in Minnesota. Journal of Wildlife Management 39:781-789.

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

  • HALL, G. 1983. BIRDS OF WV. CARNEGIE MUSEUM OF NATURAL HISTORY.

  • 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.

  • Hilty, S.L. and W. L. Brown. 1986. A Guide to the Birds of Colombia. Princeton University Press, Princeton, USA. 836 pp.

  • 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.

  • Imhof, T. A. 1976. Alabama birds. Second edition. Univ. Alabama Press, Tuscaloosa. 445 pp.

  • Jackson, G. D. 1991. Field identification of teal in North America: female-like plumages. Part I: blue-winged, cinnamon, and green-winged teal. Birding 23(3):124-133.

  • Livezey, B. C. 1991. A phylogenetic analysis and classification of recent dabbling ducks (tribe Anatini) based on comparative morphology. Auk 108:471-507.

  • Marcy, L. E. 1986. Waterfowl nest baskets. Section 5.1.3, US Army Corps of Engineers Wildlife Resources Management Manual. Tech. Rep. EL-86-15. Waterways Expt. Station, Vicksburg, Mississippi. 16 pp.

  • McAtee W.L. 1959. Folk - names of candian birds. National Museum of Canada. Folk - names of candian birds. National Museum of Canada. 74 pages.

  • Mills, Charles E. 1991. The Birds of a Southern Indiana Coal Mine Reclamation Project. 69 Ind. Aud. Q. 65-79.

  • 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.

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

  • North American Waterfowl Management Plan. 1998. Expanding the vision 1998 update. Canadian Wildlife Service. 32 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.

  • Paton, P. W. C., A. Taylor, and P. R. Ashman. 1984. Blue- winged teal nesting in Hawaii. Condor 86:219.

  • Peterson, R. T. 1980. A field guide to the birds of eastern and central North America. Fourth Edition. Houghton Mifflin Co., Boston, MA. 384 pages.

  • Peterson, R.T. 1980b. A field guide to the birds of eastern and central North America. Houghton Mifflin Company, Boston.

  • Peterson, R.T. 1990b. A field guide to western birds. Houghton Mifflin Company, Boston.

  • Poole, A. F. and F. B. Gill. 1992. The birds of North America. The American Ornithologists' Union, Washington, D.C. and The Academy of Natural Sciences, Philadelphia, PA.

  • Raffaele, H. A. 1983a. A guide to the birds of Puerto Rico and the Virgin Islands. Fondo Educativo Interamericano, San Juan, Puerto Rico. 255 pp.

  • Raffaele, H., J. Wiley, O. Garrido, A. Keith, and J. Raffaele. 1998. A guide to the birds of the West Indies. Princeton University Press, Princeton, NJ. 511 pp.

  • Rappole, J.H., Morton, E.S., Lovejoy, T.E. and Ruos, J.L. 1983. Nearctic avian migrants in the Neotropics. U.S. Department of the Interior, Fish and Wildlife Service and World Wildlife Fund, 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.

  • Ringelman, J. K., J. R. Longcore, and R. B. Owen, Jr. 1982. Nest and brood attentiveness in female Black Ducks. Condor 84:110-116.

  • Rohwer, Frank C., William P. Johnson and Elizabeth R. Loos. 2002. Blue-winged Teal. The Birds of North America. Vol. 16, No. 625. American Orinithologists' Union. The Academy of Natural Sciences of Philadelphia.

  • Root, T. 1988. Atlas of wintering North American birds: An analysis of Christmas Bird Count data. University of Chicago Press. 336 pp.

  • See SERO listing

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

  • Sinclair, P.H., W.A. Nixon, C.D. Eckert and N.L. Hughes. 2003. Birds of the Yukon Territory. UBC Press, Vancouver, BC. 595pp.

  • 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.

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

  • U.S. Fish and Wildlife Service (USFWS). 22 July 1996. Migratory bird hunting; proposed frameworks for early-season migratory bird hunting regulations. Federal Register

  • Wilkins, K.A., M.C. Otto and G.W. Smith. 2000. Trends in duck breeding populations, 1955-2000. Administrative Report. Office of Migratory Bird Management. U.S. Fish and Wildlife Service. 19 pp.

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

  • eBird. 2016. eBird: An online database of bird distribution and abundance [web application]. eBird, Cornell Lab of Ornithology, Ithaca, New York. Available: http://www.ebird.org. Accessed in 2016.

Use Guidelines & Citation

Use Guidelines and Citation

The Small Print: Trademark, Copyright, Citation Guidelines, Restrictions on Use, and Information Disclaimer.

Note: All species and ecological community data presented in NatureServe Explorer at http://explorer.natureserve.org were updated to be current with NatureServe's central databases as of March 2018.
Note: This report was printed on

Trademark Notice: "NatureServe", NatureServe Explorer, The NatureServe logo, and all other names of NatureServe programs referenced herein are trademarks of NatureServe. Any other product or company names mentioned herein are the trademarks of their respective owners.

Copyright Notice: Copyright © 2018 NatureServe, 4600 N. Fairfax Dr., 7th Floor, Arlington Virginia 22203, U.S.A. All Rights Reserved. Each document delivered from this server or web site may contain other proprietary notices and copyright information relating to that document. The following citation should be used in any published materials which reference the web site.

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.

Restrictions on Use: Permission to use, copy and distribute documents delivered from this server is hereby granted under the following conditions:
  1. The above copyright notice must appear in all copies;
  2. Any use of the documents available from this server must be for informational purposes only and in no instance for commercial purposes;
  3. Some data may be downloaded to files and altered in format for analytical purposes, however the data should still be referenced using the citation above;
  4. No graphics available from this server can be used, copied or distributed separate from the accompanying text. Any rights not expressly granted herein are reserved by NatureServe. Nothing contained herein shall be construed as conferring by implication, estoppel, or otherwise any license or right under any trademark of NatureServe. No trademark owned by NatureServe may be used in advertising or promotion pertaining to the distribution of documents delivered from this server without specific advance permission from NatureServe. Except as expressly provided above, nothing contained herein shall be construed as conferring any license or right under any NatureServe copyright.
Information Warranty Disclaimer: All documents and related graphics provided by this server and any other documents which are referenced by or linked to this server are provided "as is" without warranty as to the currentness, completeness, or accuracy of any specific data. NatureServe hereby disclaims all warranties and conditions with regard to any documents provided by this server or any other documents which are referenced by or linked to this server, including but not limited to all implied warranties and conditions of merchantibility, fitness for a particular purpose, and non-infringement. NatureServe makes no representations about the suitability of the information delivered from this server or any other documents that are referenced to or linked to this server. In no event shall NatureServe be liable for any special, indirect, incidental, consequential damages, or for damages of any kind arising out of or in connection with the use or performance of information contained in any documents provided by this server or in any other documents which are referenced by or linked to this server, under any theory of liability used. NatureServe may update or make changes to the documents provided by this server at any time without notice; however, NatureServe makes no commitment to update the information contained herein. Since the data in the central databases are continually being updated, it is advisable to refresh data retrieved at least once a year after its receipt. The data provided is for planning, assessment, and informational purposes. Site specific projects or activities should be reviewed for potential environmental impacts with appropriate regulatory agencies. If ground-disturbing activities are proposed on a site, the appropriate state natural heritage program(s) or conservation data center can be contacted for a site-specific review of the project area (see Visit Local Programs).

Feedback Request: NatureServe encourages users to let us know of any errors or significant omissions that you find in the data through (see Contact Us). Your comments will be very valuable in improving the overall quality of our databases for the benefit of all users.