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Home/Species/ Black-headed Grosbeak

Pheucticus melanocephalus

(Swainson, 1827)

Black-headed Grosbeak

G5Secure Found in 355 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
Least concernIUCN
Identity
Unique IDELEMENT_GLOBAL.2.106480
Element CodeABPBX61040
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVertebrate Animal
IUCNLeast concern
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomAnimalia
PhylumCraniata
ClassAves
OrderPasseriformes
FamilyCardinalidae
GenusPheucticus
Other Common Names
Cardinal à tête noire (FR) Picogordo Tigrillo (ES)
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/.
Taxonomic Comments
Where ranges overlap in Great Plains, hybridizes with P. ludovicianus (AOU 1998). Although regarded as conspecific by a few authors, they are properly regarded as constituting a superspecies (AOU 1998).
Conservation Status
Rank MethodExpertise without calculation
Review Date2016-04-09
Change Date1996-12-03
Range Extent Comments
BREEDS: southwestern British Columbia, east to southwestern Saskatchewan, northeastern Montana, northwestern North Dakota, south along Pacific coast to northern Baja California, central and southeastern Arizona, eastern New Mexico and south into mainland of Mexico; east to central Nebraska, central Kansas, western Oklahoma, western Texas. WINTERS: in Mexico (Terres 1980).
Ecology & Habitat

Habitat

Deciduous forest and woodland, pine-oak association, oak scrub, pinyon-juniper woodland and deciduous thickets (Subtropical and Temperate zones) (AOU 1983). Often found on edges of ponds, streams, or forests. Usually nests in open woodlands or in trees and shrubs near streams and swamps, usually 1-8 m above ground.

Ecology

Both the male and female defend their nesting territory against other breeding pairs. Jays are primary nest predators in New Mexico (Hill 1988).

Reproduction

Clutch size typically is 3-4. Incubation, by both parents, lasts 12-13 days. Altricial young are tended by both parents, leave nest in 9-12 days. See Hill (1988) for information on reproduction in New Mexico.
Terrestrial Habitats
Forest - HardwoodForest - ConiferForest - MixedWoodland - HardwoodWoodland - ConiferWoodland - MixedShrubland/chaparral
Palustrine Habitats
FORESTED WETLANDRiparian
Other Nations (2)
CanadaN5B,NUM
ProvinceRankNative
British ColumbiaS5BYes
AlbertaS3BYes
SaskatchewanSUBYes
United StatesN5B
ProvinceRankNative
South DakotaS5BYes
NevadaS4BYes
WashingtonS5BYes
WyomingS4B,S5NYes
UtahS4BYes
CaliforniaSNRBYes
KansasS3BYes
AlabamaSNRMYes
OregonS5BYes
MontanaS5BYes
TexasS4BYes
OklahomaS1NYes
ColoradoS4BYes
ArkansasSNAYes
New MexicoS5B,S5NYes
IdahoS5BYes
NebraskaS5Yes
ArizonaS5Yes
North DakotaSNRBYes
Navajo NationS4BYes
New JerseySNAYes
Roadless Areas (355)
Arizona (25)
AreaForestAcres
Black CanyonPrescott National Forest10,683
BoulderTonto National Forest40,359
Butterfly Roadless AreaCoronado National Forest42,296
Catalina St. Pk. Roadless AreaCoronado National Forest951
Cdo WsaCoronado National Forest1,955
CenterfireApache-Sitgreaves National Forests13,130
ChiricahuaCoronado National Forest76,876
GaliuroCoronado National Forest28,333
Happy ValleyCoronado National Forest7,972
HellsgateTonto National Forest6,171
Hot AirApache-Sitgreaves National Forests31,712
Lime CreekTonto National Forest42,568
MazatzalTonto National Forest16,942
Middle Dragoon RoadlessCoronado National Forest10,543
Middle Romero WSRCoronado National Forest60
NolanApache-Sitgreaves National Forests6,780
Oracle RoadlessCoronado National Forest22,365
PicachoTonto National Forest4,969
PinalenoCoronado National Forest130,920
PipestemApache-Sitgreaves National Forests34,598
Santa RitaCoronado National Forest6,078
Sierra Ancha Wilderness ContiguousTonto National Forest7,787
TumacacoriCoronado National Forest44,594
WhetstoneCoronado National Forest20,728
Willis CanyonKaibab National Forest9,688
California (135)
AreaForestAcres
AgnewSequoia National Forest9,561
AntimonyLos Padres National Forest40,911
Arroyo SecoAngeles National Forest4,703
Barker ValleyCleveland National Forest11,940
Bear MountainLos Padres National Forest913
Bell MeadowStanislaus National Forest7,968
Benton RangeInyo National Forest9,637
Birch CreekInyo National Forest28,816
Black ButteLos Padres National Forest5,116
Black CanyonInyo National Forest32,421
Black Mtn.Sequoia National Forest15,102
Blue Creek Rare ISix Rivers National Forest12,134
Bucks LakePlumas National Forest680
Cactus Springs BSan Bernardino National Forest3,106
Cahuilla MountainSan Bernardino National Forest6,952
CajonSan Bernardino National Forest7,548
CalienteCleveland National Forest5,953
Carson - IcebergStanislaus National Forest56,430
ChannellSequoia National Forest45,429
ChicoSequoia National Forest39,836
ChinquapinShasta-Trinity National Forest22,040
Chips CreekLassen National Forest29,089
Chips CreekPlumas National Forest12,940
Circle MountainSan Bernardino National Forest6,375
City CreekSan Bernardino National Forest9,997
ColdwaterCleveland National Forest8,402
Coyote NorthInyo National Forest11,932
Crystal CreekSan Bernardino National Forest6,783
Cucamonga AAngeles National Forest1,249
Cucamonga BSan Bernardino National Forest11,933
Cucamonga CSan Bernardino National Forest4,106
Cutca ValleyCleveland National Forest14,530
CuyamaLos Padres National Forest19,631
Deep CreekSan Bernardino National Forest23,869
Dennison PeakSequoia National Forest6,293
Devil GulchSierra National Forest30,490
Devil's Gate (CA)Humboldt-Toiyabe National Forest9,946
Devils RockShasta-Trinity National Forest16,209
DomeStanislaus National Forest11,085
Dry LakesLos Padres National Forest17,043
EagleStanislaus National Forest16,116
Eagle PeakCleveland National Forest6,481
East YubaTahoe National Forest17,968
Excelsior (CA)Inyo National Forest45,607
Fish CanyonAngeles National Forest29,886
Fox MountainLos Padres National Forest52,072
Glass MountainInyo National Forest52,867
Granite ChiefTahoe National Forest6,546
Granite PeakSan Bernardino National Forest450
Greenhorn CreekSequoia National Forest28,226
GrindstoneMendocino National Forest26,031
Grouse LakesTahoe National Forest19,085
Hixon FlatSan Bernardino National Forest8,095
Hoover - Mt.olsenHumboldt-Toiyabe National Forest624
Horse Creek RidgeSan Bernardino National Forest8,969
Horse Mdw.Inyo National Forest5,687
IshiLassen National Forest21,805
KangarooKlamath National Forest40,617
Kings RiverSierra National Forest52,999
LaddCleveland National Forest5,300
Log Cabin SaddlebagInyo National Forest15,165
Magic MountainAngeles National Forest15,542
Malduce BuckhornLos Padres National Forest14,177
ManzanaLos Padres National Forest2,101
MatilijaLos Padres National Forest5,218
Middle ForkPlumas National Forest29,278
Middle YubaTahoe National Forest7,379
Mill CreekLassen National Forest7,587
Mill CreekSequoia National Forest27,643
Mill PeakSan Bernardino National Forest7,884
Mokelumne - SprattHumboldt-Toiyabe National Forest613
MosesSequoia National Forest22,077
Mt. JacksonHumboldt-Toiyabe National Forest20,721
Mt. OlsenInyo National Forest2,161
Mt. Shasta AShasta-Trinity National Forest676
Mt. Shasta BShasta-Trinity National Forest2,809
Nevahbe RidgeInyo National Forest302
NightStanislaus National Forest3,173
No NameCleveland National Forest4,897
NordhoffLos Padres National Forest12,031
North Fork American RiverTahoe National Forest38,495
North Fork SmithSix Rivers National Forest37,898
North MountainStanislaus National Forest7,856
Orleans Mtn. CSix Rivers National Forest15,589
PacksaddleSix Rivers National Forest3,862
PaiuteInyo National Forest58,712
Pine CreekCleveland National Forest503
Pleasant ViewAngeles National Forest26,395
PortugueseKlamath National Forest18,915
PyramidEldorado National Forest24,347
Pyramid Peak BSan Bernardino National Forest7,194
Raywood Flat BSan Bernardino National Forest11,373
RinconSequoia National Forest54,610
Robinson PeakHumboldt-Toiyabe National Forest5,835
Rock Creek WestInyo National Forest3,626
Rouse HillSan Bernardino National Forest13,745
RussianKlamath National Forest21,771
San DimasAngeles National Forest7,160
San Gabriel AddAngeles National Forest2,527
Santa CruzLos Padres National Forest21,182
Sawmill - BadlandsLos Padres National Forest51,362
Sespe - FrazierLos Padres National Forest106,910
Sespe - FrazierAngeles National Forest4,254
Sheep MountainAngeles National Forest21,098
Sill HillCleveland National Forest5,294
Silver HillHumboldt-Toiyabe National Forest4,423
SinkardHumboldt-Toiyabe National Forest2,004
SiskiyouKlamath National Forest54,039
Siskiyou BSix Rivers National Forest18,871
Skeleton GladeMendocino National Forest9,237
Slate Mtn.Sequoia National Forest12,299
SnoozerKlamath National Forest23,414
Snow MountainMendocino National Forest14,457
Soldier CanyonInyo National Forest40,589
SoliderSix Rivers National Forest14,918
South ForkShasta-Trinity National Forest16,786
South SierraInyo National Forest41,853
South SierraSequoia National Forest8,008
Strawberry PeakAngeles National Forest7,245
SugarloafSan Bernardino National Forest8,206
TequepisLos Padres National Forest9,080
Timbered CraterLassen National Forest4,096
TinemahaInyo National Forest27,060
TrabucoCleveland National Forest23,341
Tragedy - Elephants BackEldorado National Forest20,866
WaterhouseStanislaus National Forest4,394
Weaver BallyShasta-Trinity National Forest829
West YubaTahoe National Forest16,059
WestforkAngeles National Forest4,407
Whisky CreekInyo National Forest865
White LedgeLos Padres National Forest18,632
Wild Horse Mtn. (CA)Humboldt-Toiyabe National Forest28,822
Wonoga Pk.Inyo National Forest11,272
WoodpeckerSequoia National Forest11,936
WoolstaffSequoia National Forest41,445
Colorado (5)
AreaForestAcres
Comanche Peak Adjacent AreaArapaho & Roosevelt NFs44,158
Dome PeakRoutt NF35,716
HermosaSan Juan NF148,103
Long ParkRoutt NF42,100
San MiguelSan Juan NF64,263
Idaho (9)
AreaForestAcres
Bear CreekCaribou-Targhee National Forest118,582
Borah PeakSalmon-Challis National Forest130,463
HoodooNez Perce-Clearwater National Forest153,868
Italian PeakCaribou-Targhee National Forest141,158
NeedlesPayette National Forest131,279
PalisadesCaribou-Targhee National Forest122,002
Peace RockBoise National Forest191,734
Pioneer MountainsSalmon-Challis National Forest172,460
Pioneer MountainsSawtooth National Forest119,563
Montana (22)
AreaForestAcres
Big Snowy Mountains WsaLewis and Clark National Forest88,003
Bmss Ra 1485Flathead National Forest334,275
BridgerGallatin National Forest45,059
Buckhorn Ridge (MT)Kootenai National Forest34,716
Cabin Creek Wildlife Management Area OcdGallatin National Forest35,048
Cabinet Face East #671Kootenai National Forest50,326
Cattle GulchBeaverhead-Deerlodge National Forest19,390
Freezeout MountainBeaverhead-Deerlodge National Forest97,305
Gallatin FringeGallatin National Forest51,571
HoodooLolo National Forest105,162
Hyalite - Porcupine - Buffalo Horn Wilderness Study AreaGallatin National Forest143,991
Lazyman GulchHelena National Forest11,614
Line Creek PlateauCuster National Forest24,825
LionheadGallatin National Forest33,549
Mt. Gmt Area HCuster National Forest1,335
North AbsarokaGallatin National Forest159,075
North AbsarokaCuster National Forest21,063
QuiggLolo National Forest67,267
Red Lodge Creek HellroaringCuster National Forest17,210
Scotchman Peaks (MT)Kootenai National Forest53,909
Selway - Bitterroot (01067)Bitterroot National Forest114,953
Silver KingBeaverhead-Deerlodge National Forest64,289
Nevada (19)
AreaForestAcres
Angel Peak NorthHumboldt-Toiyabe National Forest12,577
Bald Mtn.Humboldt-Toiyabe National Forest41,598
Cave CreekHumboldt-Toiyabe National Forest6,145
CottonwoodHumboldt-Toiyabe National Forest18,161
Currant - East SlopeHumboldt-Toiyabe National Forest10,101
Duck Creek Mtns.Humboldt-Toiyabe National Forest12,165
Humboldt - Angel LkHumboldt-Toiyabe National Forest1,008
North SchellHumboldt-Toiyabe National Forest30,773
Pearl PeakHumboldt-Toiyabe National Forest71,405
Red MountainHumboldt-Toiyabe National Forest30,242
Rose - EvansHumboldt-Toiyabe National Forest4,782
Rose - GalenaHumboldt-Toiyabe National Forest3,711
Rose - Whites CanyonHumboldt-Toiyabe National Forest2,568
Ruby - Lamoille CynHumboldt-Toiyabe National Forest32,771
Snake - Big WashHumboldt-Toiyabe National Forest4,146
Snake - ChokecherryHumboldt-Toiyabe National Forest30,845
South SchellHumboldt-Toiyabe National Forest125,614
Toiyabe RangeHumboldt-Toiyabe National Forest99,225
West SchellHumboldt-Toiyabe National Forest21,656
New Mexico (32)
AreaForestAcres
Apache Kid ContiguousCibola National Forest67,542
Arroyo de los FrijolesSanta Fe National Forest5,277
Aspen MountainGila National Forest23,784
Black CanyonSanta Fe National Forest1,922
Bull CanyonCarson National Forest11,512
Capitan MountainsLincoln National Forest14,069
Chama WS RiverSanta Fe National Forest4,168
Columbine - Hondo Wilderness Study AreaCarson National Forest43,739
Contiguous To Black & Aldo Leopold WildernessGila National Forest111,883
Contiguous To Gila Wilderness & Primitive AreaGila National Forest79,049
Devils CreekGila National Forest89,916
Frisco BoxGila National Forest38,979
Juan de Gabaldon GrantSanta Fe National Forest8,023
Latir PeakCarson National Forest3,573
Little TesuqueSanta Fe National Forest815
Meadow CreekGila National Forest34,167
Nichols ReservoirSanta Fe National Forest1,518
NolanGila National Forest13,051
Ortega PeakLincoln National Forest11,545
Pacheco CanyonSanta Fe National Forest1,012
Peloncillo (NM)Coronado National Forest43,339
RendijaSanta Fe National Forest2,176
Ryan HillCibola National Forest34,201
San JoseCibola National Forest16,950
Sawyers PeakGila National Forest59,743
South Guadalupe MountainsLincoln National Forest20,930
Thompson PeakSanta Fe National Forest33,001
Tucson MountainLincoln National Forest16,905
Virgin CanyonSanta Fe National Forest6,068
West Face Sacramento MountainsLincoln National Forest41,176
Wheeler Peak WildernessCarson National Forest2,677
White CapCibola National Forest8,036
Oregon (22)
AreaForestAcres
Coleman RimFremont National Forest10,638
Crane MountainFremont National Forest23,096
EagleMt. Hood National Forest16,841
ElkhornWillamette National Forest9,380
Hebo 1aSiuslaw National Forest13,930
HellholeUmatilla National Forest65,679
HomesteadWallowa-Whitman National Forest5,817
Hurricane CreekWallowa-Whitman National Forest1,606
Imnaha FaceWallowa-Whitman National Forest29,575
LarchMt. Hood National Forest12,961
Lookout MountainOchoco National Forest14,115
Metolius BreaksDeschutes National Forest11,141
Mt. EmilyWallowa-Whitman National Forest8,421
Mt. JeffersonDeschutes National Forest2,282
Mt. BaileyUmpqua National Forest18,401
ReservoirWallowa-Whitman National Forest13,641
Sheep DivideWallowa-Whitman National Forest16,201
Sky Lakes AWinema National Forest3,940
South KalmiopsisSiskiyou National Forests104,477
TenmileSiuslaw National Forest10,818
Twin MountainWallowa-Whitman National Forest58,533
Walla Walla RiverUmatilla National Forest34,416
South Dakota (1)
AreaForestAcres
Indian CreekBuffalo Gap National Grassland24,666
Texas (1)
AreaForestAcres
Big CreekNational Forests in Texas1,447
Utah (45)
AreaForestAcres
0401005Ashley National Forest38,930
418001Uinta National Forest5,697
418012Uinta National Forest25,758
418024Uinta National Forest51,699
418025Uinta National Forest32,698
418026Uinta National Forest14,038
418027Uinta National Forest13,884
418040Uinta National Forest1,702
Boulder MountainWasatch-Cache National Forest8,852
Box - Death HollowDixie National Forest3,175
Burch CreekWasatch-Cache National Forest6,938
Capital ReefDixie National Forest763
CottonwoodDixie National Forest6,754
FishhookDixie National Forest12,959
Fishlake MountainFishlake National Forest25,217
High Uintas (UT)Wasatch-Cache National Forest102,398
Hilgard MountainFishlake National Forest28,389
Joe LottFishlake National Forest19,826
LakesWasatch-Cache National Forest121,967
Lava BedsDixie National Forest14,944
Lewis PeakWasatch-Cache National Forest11,616
Lone Peak ContiguousWasatch-Cache National Forest874
Mahogany RangeWasatch-Cache National Forest11,409
Middle FrancisWasatch-Cache National Forest3,296
MogotsuDixie National Forest16,762
Mt. AireWasatch-Cache National Forest9,681
Mt. Logan NorthWasatch-Cache National Forest18,930
Mt. Logan SouthWasatch-Cache National Forest17,014
Mt. Logan WestWasatch-Cache National Forest5,285
Mt. NaomiWasatch-Cache National Forest41,922
Mt. OlympusWasatch-Cache National Forest9,982
New Home BenchDixie National Forest10,513
NoblettsWasatch-Cache National Forest3,116
North FrancisWasatch-Cache National Forest8,148
Oak CreekFishlake National Forest54,053
Pine Valley MountainsDixie National Forest57,673
Right Hand Fork LoganWasatch-Cache National Forest15,023
SanpitchManti-Lasal National Forest29,129
Solomon BasinFishlake National Forest19,963
South FrancisWasatch-Cache National Forest3,374
Temple PeakWasatch-Cache National Forest24,081
Twin PeaksWasatch-Cache National Forest6,157
Upper South ForkWasatch-Cache National Forest16,811
WellsvilleWasatch-Cache National Forest1,717
White PineWasatch-Cache National Forest1,942
Washington (21)
AreaForestAcres
Alpine Lakes Adj.Wenatchee National Forest57,104
Black CanyonOkanogan National Forest9,681
Blue SlideWenatchee National Forest17,505
EntiatWenatchee National Forest72,617
Glacier Peak KMt Baker-Snoqualmie National Forest47,269
Goat Rocks AdjWenatchee National Forest6,108
Granite MountainOkanogan National Forest27,428
Jefferson RidgeOlympic National Forest6,512
Jupiter RidgeOlympic National Forest10,148
Liberty BellOkanogan National Forest108,495
Mt. Baker MaMt Baker-Snoqualmie National Forest24,847
Mt. Baker Noisy - DiobsudMt Baker-Snoqualmie National Forest56,039
Nason RidgeWenatchee National Forest19,329
Pasayten RimOkanogan National Forest17,074
Rock CreekWenatchee National Forest32,239
SawtoothOkanogan National Forest122,194
Slide RidgeWenatchee National Forest11,430
South QuinaultOlympic National Forest11,081
TaneumWenatchee National Forest26,140
Thorp Mtn.Wenatchee National Forest22,717
Twin LakesWenatchee National Forest22,496
Wyoming (18)
AreaForestAcres
Bear RocksBighorn National Forest25,023
Grayback RidgeBridger-Teton National Forest295,113
Gros Ventre MountainsBridger-Teton National Forest106,418
Horse Creek MesaBighorn National Forest77,808
Little BighornBighorn National Forest133,949
Middle ForkShoshone National Forest51,772
Pacific Creek - Blackrock CreekBridger-Teton National Forest24,658
PalisadesTarghee National Forest1,121
Phillips RidgeBridger-Teton National Forest10,108
Salt River RangeBridger-Teton National Forest235,661
Sheep MountainMedicine Bow-Routt National Forest17,626
Sibley LakeBighorn National Forest10,367
South Beartooth HighwayShoshone National Forest105,570
Spread Creek - Gros Ventre RiverBridger-Teton National Forest166,097
Teton Corridor TrailheadsBridger-Teton National Forest286
West Slope TetonsTarghee National Forest47,448
West Slope WindsBridger-Teton National Forest143,252
Wilderness Study AreaTarghee National Forest51,961
References (22)
  1. American Ornithologists' Union (AOU). 1983. Check-list of North American Birds, 6th edition. Allen Press, Inc., Lawrence, Kansas. 877 pp.
  2. 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 <i>The Auk</i>]. Also available online: http://www.aou.org/.
  3. Balda, R. P., and G. C. Bateman. 1971. Flocking and annual cycle of the piñon jay, <i>Gymnorhinus cyanocephalus</i>. Condor 73:287-302.
  4. BirdLife International. 2004b. Threatened birds of the world 2004. CD ROM. BirdLife International, Cambridge, UK.
  5. Hagan, J. M., III, and D. W. Johnston, editors. 1992. Ecology and conservation of neotropical migrant landbirds. Smithsonian Institution Press, Washington, D.C. xiii + 609 pp.
  6. Harrison, C. 1978. A Field Guide to the Nests, Eggs and Nestlings of North American Birds. Collins, Cleveland, Ohio.
  7. Hill, G. E. 1988. Age, plumage brightness, territory quality, and reproductive success in the black-headed grosbeak. Condor 90:379-388.
  8. Horn, H. S. 1968. The adaptive significance of colonial nesting in the Brewer's Blackbird. Ecology 49:682-694.
  9. Howell, S. N. G., and S. Webb. 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press, Oxford, UK.
  10. Ligon, J. D. 1971. Late summer-autumnal breeding of the piñon jay in New Mexico. Condor 73:147-153.
  11. 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.
  12. 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.
  13. 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.
  14. Ridgely, R. S. 2002. Distribution maps of South American birds. Unpublished.
  15. Sauer, J.R., and S. Droege. 1992. Geographical patterns in population trends of Neotropical migrants in North America. Pages 26-42 in J.M. Hagan, III, and D.W. Johnston, editors. Ecology and conservation of Neotropical migrant landbirds. Smithsonian Institution Press, Washington, DC.
  16. 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.
  17. Tarvin, K. A., and G. E. Woolfenden. 1999. Blue Jay (<i>Cyanocitta cristata</i>). No. 469 IN A. Poole and F. Gill, editors. The birds of North America. The Birds of North America, Inc., Philadelphia, PA. 32pp.
  18. Terres, J. K. 1980. The Audubon Society encyclopedia of North American birds. Alfred A. Knopf, New York.
  19. Thompson, F. R., III. 1994. Temporal and spatial patterns of breeding brown-headed cowbirds in the midwestern United States. Auk 111:979-990.
  20. Williams, L. 1952b. Breeding behavior of the Brewer blackbird. Condor 54:3-47.
  21. Willson, M. F. 1966. Breeding ecology of the Yellow-headed Blackbird. Ecological Monographs 36:51-77.
  22. Zook, J. L. 2002. Distribution maps of the birds of Nicaragua, Costa Rica, and Panama. Unpublished.