Lanius ludovicianus - Linnaeus, 1766
Loggerhead Shrike
Other English Common Names: loggerhead shrike
Taxonomic Status: Accepted
Related ITIS Name(s): Lanius ludovicianus Linnaeus, 1766 (TSN 178515)
French Common Names: pie-grièche migratrice
Spanish Common Names: Alcaudón Verdugo
Unique Identifier: ELEMENT_GLOBAL.2.104527
Element Code: ABPBR01030
Informal Taxonomy: Animals, Vertebrates - Birds - Perching Birds
Image 11067

© Jeff Nadler

 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Aves Passeriformes Laniidae Lanius
Genus Size: D - Medium to large genus (21+ species)
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: Lanius ludovicianus
Taxonomic Comments: Constitutes a superspecies with L. excubitor and L. sphenocercus (AOU 1998).
Conservation Status
Help

NatureServe Status

Global Status: G4
Global Status Last Reviewed: 09Apr2016
Global Status Last Changed: 07Feb2001
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G4 - Apparently Secure
Reasons: Still widespread and common in some areas but has been declining throughout North America since the 1960s, and perhaps earlier. The decline is particularly severe in the northeastern and north-central regions. The species is now extirpated from most of the Northeast, and is nearly extirpated from Minnesota, Wisconsin, and Michigan. Part of the decline can be attributed to reforestation and loss of open habitat and thus represents a return to pre-settlement conditions when shrikes were probably absent from much of the heavily forested northern states. However, the decline has proceeded beyond what can be explained by habitat loss, as much suitable habitat remains unoccupied in most northern states. Further, decline has been recorded in all regions of the country, even those with much open habitat. Thus, the decline remains unexplained. Pesticides, loss of wintering habitat quality, and/or dependency on roadside habitat with high predation pressure have been suggested as possible causes. Of most urgent importance is research to unravel the cause of decline, and to identify critical habitat features.
Nation: United States
National Status: N4 (28Mar2001)
Nation: Canada
National Status: N3B,N3M (07Dec2017)

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 (S4), Arizona (S4), Arkansas (S3), California (S4), Colorado (S3S4B), Connecticut (SXN), Delaware (SHB), District of Columbia (SHN,SXB), Florida (S4), Georgia (S3), Idaho (S3), Illinois (S3), Indiana (S3B), Iowa (S3B,S3N), Kansas (S4B,S2N), Kentucky (S4B,S4N), Louisiana (S4), Maine (SHB,S1?N), Maryland (S1B), Massachusetts (SXB,S1N), Michigan (SNR), Minnesota (S1B), Mississippi (S4B,S4N), Missouri (S2), Montana (S3B), Navajo Nation (S4), Nebraska (S2S3), Nevada (S4), New Hampshire (SHB), New Jersey (SNA), New Mexico (S3B,S4N), New York (S1B), North Carolina (S3B,S3N), North Dakota (SU), Ohio (S1), Oklahoma (S4), Oregon (S3B,S2N), Pennsylvania (SNRB), South Carolina (S3), South Dakota (S3S4B), Tennessee (S1B,S2N), Texas (S4B), Utah (S4B,S3S4N), Vermont (SHB), Virginia (S2B,S3N), Washington (S3B), West Virginia (S1B,S2N), Wisconsin (S1B), Wyoming (S3)
Canada Alberta (S3B), Manitoba (S1B), New Brunswick (SX), Nova Scotia (SX), Ontario (S2B), Quebec (S1B), Saskatchewan (S3B)

Other Statuses

Implied Status under the U.S. Endangered Species Act (USESA): PS
Comments on USESA: The San Clemente Island (California) population (subspecies mearnsi) is listed by USFWS as Endangered. Considered of Moderate Priority on 1996 WatchList (Carter et al. 1996).
Implied Status under the Committee on the Status of Endangered Wildlife in Canada (COSEWIC):E,T
Comments on COSEWIC: The species was considered a single unit and designated Threatened in April 1986. The excubitorides and the migrans subspecies were designated separately in April 1991, and the original designation was de-activated.
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: BREEDING: California, eastern Oregon, eastern Washington, and central Alberta eastward across southern Canada to southwestern New Brunswick and Nova Scotia, and south to southern Baja California, throughout Mexico to Oaxaca and Veracruz,the Gulf Coast, and southern Florida (AOU 1983). Recently has been disappearing from the northeastern portion of the breeding range. In the northeastern U.S., breeds in in western Maryland, extreme eastern West Virginia, and Virginia (perhaps several dozen pairs); extirpated elsewhere (Bartgis 1992, R. W. MacDonald pers. comm.). NON-BREEDING: central Washington, eastern Oregon, California, southern Nevada, northern Arizona, northern New Mexico, and (east of the Rockies) the southern half of breeding range south to the Gulf Coast, southern Florida, and Mexico (AOU 1983).

Area of Occupancy: 2,501 to >12,500 4-km2 grid cells
Area of Occupancy Comments: Resident throughout southern half of US and also breeds in parts of Canada and north central US. Actual area of occupancy unknown.

Number of Occurrences: 81 to >300
Number of Occurrences Comments: This species is represented by a large number of occurrences (subpopulations). It has an extremely large range and population size (Birdlife International, 2014) and Partners in Flight (2013) estimates a global population of almost six million individuals.

Population Size: >1,000,000 individuals
Population Size Comments: Based on Partners in Flight numbers (2013).

Number of Occurrences with Good Viability/Integrity: Some to very many (13 to >125)
Viability/Integrity Comments: With such a large range and population size, the species should have at least some good element occurrences. Actual number unknown.

Overall Threat Impact: High
Overall Threat Impact Comments: PESTICIDES: Since shrikes are high on the food chain, pesticides have been implicated as a potential cause of the decline (Fraser and Luukkonen 1986). DDE, a metabolite of DDT, has been detected in eggs from Illinois and Virginia (Anderson and Duzan 1978), but crushed eggs associated with eggshell thinning have not been reported. While there is evidence of some eggshell thinning in Illinois, there is no apparent eggshell thinning in California and Florida (Hands et al. 1989). The relatively high nesting and fledging success rate in the areas of marked decline indicate that pesticides have not reduced reproduction (Brooks 1988, Gawlik and Bildstein 1990, Kridelbaugh 1982, Luukkonen 1987, Novak 1989). Young exposed to dieldrin have been shown to attack and kill prey more slowly than unexposed birds (Busbee 1977). Wide-scale use of organochlorides was curtailed in the U.S. in the 1970s, yet the population decline continues. Blumton et al. (1989) reported that necropsies on six Virginia shrikes showed traces of pesticide contamination, but drew no conclusions on the relationship between contamination and mortality. Pesticides may pose a greater threat in reducing food availability; clutch and brood sizes declined after the introduction of organochlorines; and significant declines on the Canadian prairies corresponded with dieldrin treatment of grasshoppers, which make up 30-75% of the diet (Yosef 1996, Yosef 1994, C. Campbell in Cadman 1985).

FOOD AVAILABILITY: Pesticides may affect populations through reducing food availability (see comments under PESTICIDES above). In Virginia, Luukkonen (1987) reported several nests with malnourished nestlings and developmental variability within a brood, both evidence of limited food availability at some sites. However, on a broader scale, early breeding, brood reduction, and multiple broods should off-set any local problems from food shortages, at least for the nesting season (Luukkonen 1987). In the Midwest, excessive winter mortality may be an important cause of the decline; reduced food supplies may weaken shrikes and cause them to move into woodlots occupied by raptors (Byrd and Johnston 1991).

PREDATION: Predation is the leading cause of nest failure, but nest predation does not appear to constitute an important limiting factor (Bartgis 1992).

BREEDING HABITAT LOSS/DEGRADATION: Limited evidence from most of the Northeast suggests that lack of suitable breeding habitat limits abundance in this region. Habitat loss has been caused by farmland abandonment, development, and widespread changes in farming practices (Novak 1989). Although acreage in pasture has decreased dramatically since World War II in New York and Virginia, there apparently is a substantial amount of unoccupied habitat remaining in both states (Luukkonen 1987, Novak 1989). There also seems to be considerable unoccupied breeding habitat in Maryland and West Virginia (Bartgis, pers. comm.). At least on a local level in Virginia, habitat loss may be the primary problem (Ridd, pers. comm.). Luukkonen (1987) expressed concerns about the fragmenting of potential habitat into islands in the Ridge and Valley of Virginia. Occasional use of marginal habitat may be partially to blame for the decline in Virginia. In southern Idaho, nearly 70% of original sagebrush steppe has been destroyed by agriculture and other development (Woods 1994). In the north-central states, however, habitat loss may explain some of the decline, but not all of it. In Missouri, declining populations coincided with regions with the highest proportion of lands being converted from pasture to row crops (Kridelbaugh 1982). Several reports have concluded that much suitable habitat remains unoccupied in Michigan, Minnesota, and Wisconsin, although shrikes now are nearly absent from these states (Brooks and Temple 1990, Robbins 1991). However, Luukkonen (pers. comm.) questioned the availability of adequately sized pastures for habitat in Michigan. Threats in western Canada (Telfer et al. 1989) include habitat loss such as the conversion of unimproved pasture to cropland (Telfer 1992). In eastern Canada, declines probably have been due to loss of breeding habitat to changing agricultural practices, industrial development, residential development, and vegetation succession (Cadman 1986, 1991). Yosef and Grubb (1992) suggested that a human-caused reduction in the number of hunting perches is at least partially responsible for the decline.

WINTER HABITAT LOSS: Populations that winter along the Gulf Coast have lost much habitat, and remaining habitats are often impoverished by red fire-ants and associated pesticide-control procedures (Lymn and Temple 1991). Because of relatively high reproductive success in southern Minnesota, Brooks (1988) concluded that the 20% mean annual rate of decline in the population in the region was "probably due to factors on their nonbreeding range" to the south. Brooks (1988) further summarized concerns that the decline in Minnesota is possibly caused by decreases in winter habitat in the breeding birds' wintering range. She stated that "if resident (southern) shrike populations are being limited by habitat availability, migrant shrikes wintering in the same area are almost certainly being forced to occupy marginal habitats that are not being held by territorial residents." However, a banding study in Missouri indicated that the winter and summer populations in that state are completely separate (Kridelbaugh 1982). Conclusive evidence that factors during the nonbreeding season are limiting is not available (Yosef 1994).

COWBIRD PARASITISM/NEST PREDATION: A study documented cowbird nest parasitism in shrikes in Iowa, but the frequency was very low, only 3 out of 261 nests (DeGeus 1991). The same study found a high incidence of nest predation among shrikes nesting along roadsides (86% of all losses), and only 35% nesting success overall. Predation is apparently more intense in roadside and other linear habitats (DeGeus 1990). If shrikes are utilizing roadside habitat extensively throughout their range, high nest predation may be one explanation for their decline.

OTHER MORTALITY: Locally, mortality from vehicle collisions may be significant. A high incidence of automobile-caused mortality was noted by Miller (1931). Shrikes typically fly low to the ground, sometimes across roadways, and often feed on roads. Inexperienced juveniles have been observed following adults across highways and learning from adults to feed on highways (Hershberger 1989, Novak 1989). In many areas, hedgerows, barbed-wire fences, and other habitat features utilized by shrikes are concentrated along roadways. Fledglings and other juveniles are frequently killed by automobiles. Automobile collisions killed all three fledglings produced at an Ontario nest and four of seven young fledged over three years at a New York site (Novak 1989). Juveniles killed by vehicle collisions in the summer have also been observed in both Virginias (Bartgis 1989, Luukkonen 1987) and Maryland (Hershberger 1990). Blumton et al. (1989) reported that automobiles accounted for 29% of the observed fall and winter mortality among Virginia shrikes.

FIRE ANTS: In Florida, Yosef and Lohrer (1995) found no evidence of an effect of imported red fire-ants on territory size and prey capture rate, but cautioned that insecticides used to control red fire-ants are likely to be detrimental (see PESTICIDES and WINTER HABITAT LOSS).

DISTURBANCE: Shrikes are not particularly alarmed by proximity to human activity. Brooks (1988) noted that nests near buildings had a success rate similar to those farther away from buildings. In Virginia, a shrike continued to incubate a nest in a tree after the top was trimmed off (Luukkonen 1987), although a Maryland nest in a tree was abandoned after a multiflora rose concealing it was killed with herbicide (Dean, pers. comm.). Some shrikes have nested less than 3 m from a road, but were not flushed by passing vehicles (Bartgis 1989, Luukkonen 1987). Food shortages may occasionally limit nesting success.

Short-term Trend: Decline of 10-50%
Short-term Trend Comments: North American Breeding Bird Survey (BBS) data indicate a significant 1.80% annual decline occurred in North America from 2002 to 2012 (Sauer, et. al. 2014). BBS data for 1980-2000 indicated ongoing, significant declines, although the rates of these declines were slowing down for some populations. Rangewide, the decline was 2.2% annually for this 20 year period (Sauer et al. 2001). Regionally, the declines were 3% annually (46% overall) for the eastern region, 1.9% annually (32% overall) for the central region, and 1.6% annually (28% overall) for the west.

Even though there is no evidence to suggest that the species has recovered to any great extent since 1980, it is still common enough in most of the southern portion of its range that most states in the region do not provide special protection or monitor populations.

Long-term Trend: Decline of 70-90%
Long-term Trend Comments: This species has undergone a large and statistically significant decrease over the last 40 years in North America (-71.2% decline over 40 years, equating to a -26.7% decline per decade; data from Breeding Bird Survey and/or Christmas Bird Count: Butcher a. (Birdlife International, 2014)). Has declined significantly nearly rangewide (Robbins et al. 1986, Sauer et al. 2001). A slow decline began in the 1930s and continued until the late 1960s and 1970s when the decline accelerated. This pattern is well-documented in the literature for all but the Southern Great Plains and the West (Fruth 1988). North American Breeding Bird Survey (BBS) data for the period 1966-2000 indicate a 71% population decline rangewide (-3.6% annually), with regional declines of 78% in the east, 65% in the central region, and 75% in the western region. Since declines began before 1966, these are conservative figures for overall declines during the past century. Christmas Bird Count data for 1961-1978 documented a 22% decline in winter sightings nationwide (Morrison 1981). Declined in recent decades in western Canada (Telfer et al. 1989, Telfer 1992) and in eastern Canada (Cadman 1986, 1991).

Intrinsic Vulnerability: Not intrinsically vulnerable
Intrinsic Vulnerability Comments: Reproductive rates are potentially high; could expand current numbers and range if the factors responsible for decline could be eliminated (Yosef 1996).

Environmental Specificity: Moderate to broad.
Environmental Specificity Comments: Inhabitas ecotones and may not be as tolerant of human-induced changes as other species (Yosef, 1996).

Other NatureServe Conservation Status Information

Inventory Needs: Continue monitoring the population levels of this declining species within Florida.

Protection Needs: The most effective land protection for shrikes will probably require regional land use planning tools, such as zoning, special agricultural districts, and agricultural easements, that will help maintain large areas of suitable habitat. Sites with both regular summer and winter use should be priorities for protection in the Northeast. In many circumstances, acquisition may be unfeasible because of agricultural land values and the need to keep the land in production in order to maintain it as shrike habitat. Acquisition may also be of limited value until the cause of the decline can be determined. In New York, Maryland, and the Virginias, landowner contact programs will probably be more effective. These programs can appeal to a farm owner's sense of pride in the land while offering guidance to assure that key landscape features, such as suitable nest trees, are maintained. Because of the limited opportunities for habitat acquisition, existing federal facilities within primary shrike range, such as Antietam National Battlefield and the Leetown National Fisheries Center, should be encouraged to manage for shrike habitat when appropriate (Bartgis 1992).

Distribution
Help
Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) BREEDING: California, eastern Oregon, eastern Washington, and central Alberta eastward across southern Canada to southwestern New Brunswick and Nova Scotia, and south to southern Baja California, throughout Mexico to Oaxaca and Veracruz,the Gulf Coast, and southern Florida (AOU 1983). Recently has been disappearing from the northeastern portion of the breeding range. In the northeastern U.S., breeds in in western Maryland, extreme eastern West Virginia, and Virginia (perhaps several dozen pairs); extirpated elsewhere (Bartgis 1992, R. W. MacDonald pers. comm.). NON-BREEDING: central Washington, eastern Oregon, California, southern Nevada, northern Arizona, northern New Mexico, and (east of the Rockies) the southern half of breeding range south to the Gulf Coast, southern Florida, and Mexico (AOU 1983).

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 AL, AR, AZ, CA, CO, CTextirpated, DCextirpated, DE, FL, GA, IA, ID, IL, IN, KS, KY, LA, MAextirpated, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NN, NV, NY, OH, OK, OR, PA, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY
Canada AB, MB, NBextirpated, NSextirpated, ON, QC, SK

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)
AZ Apache (04001), Coconino (04005), La Paz (04012), Navajo (04017), Yuma (04027)
CA Alameda (06001), Butte (06007), Contra Costa (06013), Fresno (06019), Imperial (06025), Inyo (06027), Kern (06029), Los Angeles (06037), Merced (06047), Monterey (06053), Riverside (06065), San Bernardino (06071), San Diego (06073), San Joaquin (06077), San Luis Obispo (06079), Stanislaus (06099), Tulare (06107)
DE New Castle (10003)*, Sussex (10005)*
GA Chatham (13051), Glynn (13127), Lowndes (13185), Mcintosh (13191)
ID Ada (16001), Bannock (16005), Bear Lake (16007), Butte (16023), Camas (16025), Cassia (16031), Clark (16033), Custer (16037), Elmore (16039), Gooding (16047), Jefferson (16051), Jerome (16053), Lincoln (16063), Oneida (16071), Owyhee (16073), Twin Falls (16083), Valley (16085)
IL Adams (17001)*, Alexander (17003), Bond (17005), Bureau (17011), Carroll (17015), Cass (17017)*, Champaign (17019)*, Christian (17021), Clay (17025), Clinton (17027), Coles (17029)*, Crawford (17033)*, Cumberland (17035), DeKalb (17037)*, DuPage (17043), Edwards (17047), Effingham (17049), Fayette (17051), Greene (17061)*, Grundy (17063), Hancock (17067), Henry (17073), Jackson (17077), Jasper (17079), Jefferson (17081), Jo Daviess (17085), Johnson (17087), Kane (17089)*, Kendall (17093), La Salle (17099), Lawrence (17101), Lee (17103), Marion (17121), Mason (17125), Massac (17127)*, Mcdonough (17109), Mclean (17113), Menard (17129)*, Mercer (17131), Monroe (17133), Morgan (17137)*, Moultrie (17139)*, Ogle (17141)*, Peoria (17143), Perry (17145), Piatt (17147)*, Pike (17149)*, Pope (17151)*, Pulaski (17153), Putnam (17155)*, Randolph (17157)*, Richland (17159), Saline (17165), Sangamon (17167)*, Shelby (17173)*, St. Clair (17163)*, Stark (17175), Tazewell (17179), Union (17181), Wabash (17185), Washington (17189)*, Wayne (17191), Whiteside (17195), Will (17197), Winnebago (17201), Woodford (17203)
IN Adams (18001)*, Allen (18003), Clark (18019), Clay (18021)*, Clinton (18023)*, Daviess (18027), Dearborn (18029)*, Delaware (18035)*, Dubois (18037), Elkhart (18039)*, Gibson (18051), Greene (18055), Hamilton (18057)*, Hancock (18059)*, Harrison (18061), Jackson (18071)*, Jasper (18073), Knox (18083), La Porte (18091), Lagrange (18087), Lake (18089)*, Lawrence (18093), Madison (18095)*, Marion (18097), Martin (18101), Montgomery (18107)*, Newton (18111), Ohio (18115), Orange (18117), Owen (18119), Parke (18121), Perry (18123), Pike (18125), Porter (18127), Posey (18129), Putnam (18133), Randolph (18135), Rush (18139), Spencer (18147), St. Joseph (18141), Sullivan (18153), Tippecanoe (18157)*, Vanderburgh (18163), Vigo (18167), Wabash (18169)*, Warrick (18173), White (18181), Whitley (18183)*
MA Berkshire (25003)*, Essex (25009)*, Franklin (25011)*, Hampshire (25015)*, Plymouth (25023)*, Worcester (25027)*
MD Baltimore (city) (24510)*, Baltimore County (24005)*, Carroll (24013)*, Frederick (24021)*, Montgomery (24031)*, Washington (24043)*
MI Allegan (26005)*, Alpena (26007)*, Benzie (26019)*, Chippewa (26033)*, Clare (26035)*, Emmet (26047)*, Grand Traverse (26055)*, Huron (26063)*, Manistee (26101)*, Missaukee (26113)*, Oceana (26127)*, Osceola (26133)*, Presque Isle (26141)*
MN Aitkin (27001), Anoka (27003), Benton (27009), Big Stone (27011), Blue Earth (27013), Brown (27015), Carver (27019), Chippewa (27023), Chisago (27025), Clay (27027), Cottonwood (27033), Dakota (27037), Dodge (27039), Douglas (27041), Fillmore (27045), Freeborn (27047), Goodhue (27049), Grant (27051), Hennepin (27053), Houston (27055), Jackson (27063), Lac Qui Parle (27073), Le Sueur (27079), Lincoln (27081), Lyon (27083), Meeker (27093), Morrison (27097), Murray (27101), Olmsted (27109), Otter Tail (27111), Pipestone (27117), Polk (27119), Pope (27121), Redwood (27127), Rice (27131), Scott (27139), Sherburne (27141), Sibley (27143), Steele (27147), Stevens (27149), Swift (27151), Wabasha (27157), Waseca (27161), Washington (27163), Wilkin (27167), Winona (27169), Wright (27171), Yellow Medicine (27173)
MO Adair (29001), Atchison (29005), Barton (29011), Benton (29015), Buchanan (29021), Carroll (29033), Cass (29037), Cedar (29039), Dade (29057), Daviess (29061), DeKalb (29063), Dunklin (29069), Harrison (29081), Henry (29083), Holt (29087), Lawrence (29109), Macon (29121), Mississippi (29133), Nodaway (29147), Pemiscot (29155), Pettis (29159), Saline (29195), St. Clair (29185), Stoddard (29207), Vernon (29217), Wright (29229)
MS Alcorn (28003)*, Chickasaw (28017)*, Claiborne (28021)*, Forrest (28035)*, Grenada (28043), Hinds (28049)*, Holmes (28051)*, Jackson (28059)*, Lamar (28073), Lauderdale (28075)*, Montgomery (28097), Oktibbeha (28105)*, Pearl River (28109)*, Rankin (28121)*
MT Big Horn (30003), Blaine (30005), Broadwater (30007), Carbon (30009), Carter (30011), Cascade (30013), Chouteau (30015), Custer (30017), Dawson (30021), Fallon (30025), Fergus (30027), Garfield (30033), Golden Valley (30037), Hill (30041), Jefferson (30043), Liberty (30051), McCone (30055), Meagher (30059), Musselshell (30065), Petroleum (30069), Phillips (30071), Powder River (30075), Prairie (30079), Richland (30083), Roosevelt (30085), Rosebud (30087), Sheridan (30091), Stillwater (30095), Teton (30099), Toole (30101), Valley (30105), Wheatland (30107), Wibaux (30109), Yellowstone (30111)
ND Sioux (38085), Stark (38089), Walsh (38099)*
NE Arthur (31005), Brown (31017), Cherry (31031), Keya Paha (31103), Lancaster (31109), Loup (31115), Pierce (31139), Platte (31141), Wayne (31179), York (31185)
NJ Middlesex (34023), Monmouth (34025), Morris (34027)
NM Cibola (35006), Eddy (35015), Mckinley (35031), Otero (35035), Sandoval (35043)
NY Clinton (36019), Franklin (36033), Jefferson (36045), Lewis (36049)*, Monroe (36055)*, Oneida (36065)*, Orleans (36073), St. Lawrence (36089)
OH Adams (39001), Brown (39015), Clark (39023), Fayette (39047), Hamilton (39061), Highland (39071), Madison (39097), Pickaway (39129), Seneca (39147), Union (39159)*, Warren (39165), Wood (39173)
OK Alfalfa (40003), Beaver (40007), Cimarron (40025), Comanche (40031), Ellis (40045), Grant (40053), Harmon (40057), Harper (40059), Jefferson (40067), Kiowa (40075), Major (40093), McClain (40087), Oklahoma (40109), Roger Mills (40129), Stephens (40137), Texas (40139), Tillman (40141)
PA Adams (42001), Allegheny (42003)*, Beaver (42007)*, Blair (42013)*, Crawford (42039)*, Erie (42049)*, Franklin (42055), Greene (42059)*, Lawrence (42073)*, Mercer (42085)*
SC Florence (45041)*
SD Bennett (46007), Custer (46033), Faulk (46049), Hughes (46065), Jackson (46071)*, Pennington (46103), Perkins (46105), Sanborn (46111), Shannon (46113), Stanley (46117)
TN Carroll (47017), Dyer (47045), Loudon (47105), Rutherford (47149)
VA Augusta (51015), Bath (51017), Bland (51021)*, Botetourt (51023)*, Clarke (51043), Culpeper (51047), Cumberland (51049), Fauquier (51061), Giles (51071), Greensville (51081), Highland (51091)*, Lee (51105), Loudoun (51107), Lunenburg (51111), Montgomery (51121), Prince George (51149)*, Pulaski (51155), Roanoke (51161)*, Roanoke (City) (51770)*, Russell (51167), Scott (51169), Smyth (51173), Tazewell (51185), Warren (51187), Washington (51191), Wythe (51197)
VT Addison (50001)*
WA Adams (53001)+, Benton (53005)+, Douglas (53017)+, Franklin (53021)+, Grant (53025)+, Kittitas (53037)+, Klickitat (53039)+, Lincoln (53043)+, Okanogan (53047)+, Walla Walla (53071)+, Yakima (53077)+
WI Ashland (55003), Barron (55005), Chippewa (55017), Columbia (55021), Dane (55025), Door (55029), Dunn (55033), Eau Claire (55035), Green (55045), Iowa (55049), Juneau (55057), La Crosse (55063), Marquette (55077), Menominee (55078)*, Monroe (55081), Oconto (55083), Ozaukee (55089), Pepin (55091)*, Polk (55095), Portage (55097), Richland (55103), Rock (55105), Rusk (55107), Sauk (55111), St. Croix (55109), Trempealeau (55121)
WV Berkeley (54003), Grant (54023), Greenbrier (54025), Hampshire (54027)*, Hardy (54031), Jefferson (54037), Mineral (54057), Monroe (54063), Pocahontas (54075)
WY Albany (56001), Big Horn (56003), Campbell (56005), Carbon (56007), Converse (56009), Crook (56011), Fremont (56013), Goshen (56015), Hot Springs (56017), Johnson (56019), Laramie (56021), Lincoln (56023), Natrona (56025), Niobrara (56027), Park (56029), Platte (56031), Sheridan (56033), Sublette (56035), Sweetwater (56037), Teton (56039), Uinta (56041), Washakie (56043), Weston (56045)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
01 Deerfield (01080203)+*, Charles (01090001)+*
02 Mohawk (02020004)+*, Hackensack-Passaic (02030103)+, Sandy Hook-Staten Island (02030104)+, Raritan (02030105)+, Brandywine-Christina (02040205)+*, Broadkill-Smyrna (02040207)+*, Upper Juniata (02050302)+*, Lower Susquehanna-Swatara (02050305)+, Gunpowder-Patapsco (02060003)+*, South Branch Potomac (02070001)+, North Branch Potomac (02070002)+, Conococheague-Opequon (02070004)+, South Fork Shenandoah (02070005)+, Shenandoah (02070007)+, Middle Potomac-Catoctin (02070008)+, Monocacy (02070009)+, Rapidan-Upper Rappahannock (02080103)+, Upper James (02080201)+, Middle James-Willis (02080205)+, Lower James (02080206)+*, Appomattox (02080207)+*
03 Upper Roanoke (03010101)+*, Meheriin (03010204)+, Lower Pee Dee (03040201)+*, Ogeechee Coastal (03060204)+, Altamaha (03070106)+, Cumberland-St. Simons (03070203)+, Alapaha (03110202)+, Upper Tombigbee (03160101)+*, Noxubee (03160108)+*, Chunky-Okatibbee (03170001)+*, Upper Leaf (03170004)+*, Black (03170007)+, Mississippi Coastal (03170009)+*, Middle Pearl-Strong (03180002)+*
04 Bad-Montreal (04010302)+, Waiska (04020203)+*, Manitowoc-Sheboygan (04030101)+, Door-Kewaunee (04030102)+, Duck-Pensaukee (04030103)+, Oconto (04030104)+*, Upper Fox (04030201)+, Little Calumet-Galien (04040001)+, St. Joseph (04050001)+, Black-Macatawa (04050002)+*, Pere Marquette-White (04060101)+*, Muskegon (04060102)+*, Betsie-Platte (04060104)+*, Boardman-Charlevoix (04060105)+*, Lone Lake-Ocqueoc (04070003)+*, Thunder Bay (04070006)+*, Pigeon-Wiscoggin (04080103)+*, Cedar-Portage (04100010)+, Sandusky (04100011)+, Chautauqua-Conneaut (04120101)+*, Oak Orchard-Twelvemile (04130001)+, Irondequoit-Ninemile (04140101)+*, Black (04150101)+, Chaumont-Perch (04150102)+, Upper St. Lawrence (04150301)+, English-Salmon (04150307)+, Otter Creek (04150402)+*, Lake Champlain (04150408)+
05 Lower Monongahela (05020005)+*, Upper Ohio (05030101)+*, Shenango (05030102)+*, Upper New (05050001)+, Middle New (05050002)+, Greenbrier (05050003)+, Upper Scioto (05060001)+, Lower Scioto (05060002)+, Paint (05060003)+, Upper Great Miami (05080001)+, Ohio Brush-Whiteoak (05090201)+, Little Miami (05090202)+, Middle Ohio-Laughery (05090203)+, Upper Wabash (05120101)+, Eel (05120104)+*, Tippecanoe (05120106)+, Wildcat (05120107)+*, Middle Wabash-Little Vermilion (05120108)+, Sugar (05120110)+*, Middle Wabash-Busseron (05120111)+, Embarras (05120112)+, Lower Wabash (05120113)+, Little Wabash (05120114)+, Skillet (05120115)+, Upper White (05120201)+, Lower White (05120202)+, Eel (05120203)+, Driftwood (05120204)+*, Flatrock-Haw (05120205)+, Upper East Fork White (05120206)+*, Lower East Fork White (05120208)+, Patoka (05120209)+, Stones (05130203)+, Blue-Sinking (05140104)+, Lower Ohio-Little Pigeon (05140201)+, Highland-Pigeon (05140202)+, Lower Ohio-Bay (05140203)+*, Saline (05140204)+, Lower Ohio (05140206)+*
06 South Fork Holston (06010102)+, Lower Little Tennessee (06010204)+, Upper Clinch (06010205)+, Powell (06010206)+
07 Elk-Nokasippi (07010104)+, Crow Wing (07010106)+*, Long Prairie (07010108)+, Platte-Spunk (07010201)+, Clearwater-Elk (07010203)+, Crow (07010204)+, Twin Cities (07010206)+, Upper Minnesota (07020001)+, Pomme De Terre (07020002)+, Lac Qui Parle (07020003)+, Hawk-Yellow Medicine (07020004)+, Chippewa (07020005)+, Redwood (07020006)+*, Middle Minnesota (07020007)+, Cottonwood (07020008)+, Blue Earth (07020009)+, Le Sueur (07020011)+, Lower Minnesota (07020012)+, Lower St. Croix (07030005)+, Rush-Vermillion (07040001)+, Cannon (07040002)+, Buffalo-Whitewater (07040003)+*, Zumbro (07040004)+, La Crosse-Pine (07040006)+, Root (07040008)+, Lower Chippewa (07050005)+, Eau Claire (07050006)+, Red Cedar (07050007)+, Coon-Yellow (07060001)+, Upper Iowa (07060002)+, Apple-Plum (07060005)+, Castle Rock (07070003)+, Lower Wisconsin (07070005)+, Flint-Henderson (07080104)+, Shell Rock (07080202)+, Crawfish (07090002)+, Pecatonica (07090003)+, Sugar (07090004)+, Lower Rock (07090005)+, Kishwaukee (07090006)+*, Green (07090007)+, Des Moines Headwaters (07100001)+, Upper Des Moines (07100002)+, East Fork Des Moines (07100003)+, The Sny (07110004)+*, North Fork Salt (07110005)+, Kankakee (07120001)+, Iroquois (07120002)+, Des Plaines (07120004)+, Upper Illinois (07120005)+, Lower Fox (07120007)+, Lower Illinois-Senachwine Lake (07130001)+, Vermilion (07130002)+, Lower Illinois-Lake Chautauqua (07130003)+, Mackinaw (07130004)+, Spoon (07130005)+, Upper Sangamon (07130006)+*, South Fork Sangamon (07130007)+, Lower Sangamon (07130008)+*, Salt (07130009)+*, La Moine (07130010)+, Lower Illinois (07130011)+*, Macoupin (07130012)+*, Cahokia-Joachim (07140101)+*, Upper Mississippi-Cape Girardeau (07140105)+, Big Muddy (07140106)+, Cache (07140108)+, Upper Kaskaskia (07140201)+*, Middle Kaskaskia (07140202)+, Lower Kaskaskia (07140204)+
08 Obion (08010202)+, South Fork Obion (08010203)+, Upper Hatchie (08010207)+*, New Madrid-St. Johns (08020201)+, Lower St. Francis (08020203)+, Little River Ditches (08020204)+, Yalobusha (08030205)+, Lower Mississippi-Natchez (08060100)+*, Upper Big Black (08060201)+*, Lower Big Black (08060202)+*
09 Bois De Sioux (09020101)+, Otter Tail (09020103)+, Upper Red (09020104)+, Buffalo (09020106)+, Eastern Wild Rice (09020108)+, Sandhill-Wilson (09020301)+, Red Lake (09020303)+, Park (09020310)+*
10 Jefferson (10020005)+, Upper Missouri (10030101)+, Upper Missouri-Dearborn (10030102)+, Smith (10030103)+, Sun (10030104)+, Marias (10030203)+, Willow (10030204)+, Teton (10030205)+, Bullwhacker-Dog (10040101)+, Arrow (10040102)+, Fort Peck Reservoir (10040104)+, Big Dry (10040105)+, Little Dry (10040106)+, Upper Musselshell (10040201)+, Middle Musselshell (10040202)+, Flatwillow (10040203)+, Box Elder (10040204)+, Lower Musselshell (10040205)+, Upper Milk (10050002)+, Middle Milk (10050004)+, Big Sandy (10050005)+, Sage (10050006)+, Lodge (10050007)+, Battle (10050008)+, Peoples (10050009)+, Cottonwood (10050010)+, Lower Milk (10050012)+, Frenchman (10050013)+, Beaver (10050014)+, Rock (10050015)+, Porcupine (10050016)+, Prarie Elk-Wolf (10060001)+, Redwater (10060002)+, Big Muddy (10060006)+, Upper Yellowstone-Lake Basin (10070004)+, Clarks Fork Yellowstone (10070006)+, Upper Yellowstone-Pompeys Pillar (10070007)+, Upper Wind (10080001)+, Little Wind (10080002)+, Popo Agie (10080003)+, Lower Wind (10080005)+, Badwater (10080006)+, Upper Bighorn (10080007)+, Nowood (10080008)+, Greybull (10080009)+, Big Horn Lake (10080010)+, Shoshone (10080014)+, Little Bighorn (10080016)+, Upper Tongue (10090101)+, Lower Tongue (10090102)+, Middle Fork Powder (10090201)+, Upper Powder (10090202)+, South Fork Powder (10090203)+, Salt (10090204)+, Crazy Woman (10090205)+, Clear (10090206)+, Middle Powder (10090207)+, Little Powder (10090208)+, Lower Powder (10090209)+, Mizpah (10090210)+, Lower Yellowstone-Sunday (10100001)+, Big Porcupine (10100002)+, Rosebud (10100003)+, Lower Yellowstone (10100004)+, Upper Little Missouri (10110201)+, Boxelder (10110202)+, Beaver (10110204)+, Antelope (10120101)+, Dry Fork Cheyenne (10120102)+, Upper Cheyenne (10120103)+, Beaver (10120107)+, Hat (10120108)+, Middle Cheyenne-Spring (10120109)+, Upper Belle Fourche (10120201)+, Upper Lake Oahe (10130102)+, Upper Heart (10130202)+, Lower Cannonball (10130206)+, Upper Moreau (10130305)+, Fort Randall Reservoir (10140101)+, Bad (10140102)+, Upper White (10140201)+, Middle White (10140202)+, Little White (10140203)+, Niobrara Headwaters (10150002)+, Middle Niobrara (10150004)+, Snake (10150005)+, Keya Paha (10150006)+, Middle James (10160006)+, Snake (10160008)+, Lower Big Sioux (10170203)+, Rock (10170204)+, Upper North Platte (10180002)+, Pathfinder-Seminoe Reservoirs (10180003)+, Medicine Bow (10180004)+, Little Medicine Bow (10180005)+, Sweetwater (10180006)+, Middle North Platte-Casper (10180007)+, Glendo Reservoir (10180008)+, Middle North Platte-Scotts Bluff (10180009)+, Upper Laramie (10180010)+, Lower Laramie (10180011)+, Horse (10180012)+, Upper Lodgepole (10190015)+, Salt (10200203)+, Dismal (10210002)+, Upper North Loup (10210006)+, Loup (10210009)+, North Fork Elkhorn (10220002)+, Tarkio-Wolf (10240005)+, Platte (10240012)+, One Hundred and Two (10240013)+, Upper Big Blue (10270201)+, Upper Grand (10280101)+, Lower Grand (10280103)+, Little Chariton (10280203)+, Little Osage (10290103)+, Marmaton (10290104)+, Harry S. Missouri (10290105)+, Sac (10290106)+, South Grand (10290108)+, Lake of the Ozarks (10290109)+, Upper Gasconade (10290201)+, Lamine (10300103)+, Blackwater (10300104)+
11 Upper Cimarron (11040002)+, Upper Cimarron-Liberal (11040006)+, Lower Cimarron-Eagle Chief (11050001)+, Lower Cimarron-Skeleton (11050002)+, Lower Salt Fork Arkansas (11060004)+, Spring (11070207)+, Upper Beaver (11100101)+, Lower Beaver (11100201)+, Lower Wolf (11100203)+, Lower Salt Fork Red (11120202)+, Middle North Fork Red (11120302)+, Lower North Fork Red (11120303)+, Blue-China (11130102)+, Farmers-Mud (11130201)+, Cache (11130202)+, West Cache (11130203)+, Northern Beaver (11130208)+, Middle Washita (11130303)+
13 Rio Puerco (13020204)+, Arroyo Chico (13020205)+, Rio San Jose (13020207)+, Tularosa Valley (13050003)+, Delaware (13070002)+
14 Upper Green (14040101)+, New Fork (14040102)+, Upper Green-Slate (14040103)+, Big Sandy (14040104)+, Bitter (14040105)+, Upper Green-Flaming Gorge Reservoir (14040106)+, Blacks Fork (14040107)+, Muddy (14040108)+, Vermilion (14040109)+, Great Divide closed basin (14040200)+, Little Snake (14050003)+, Muddy (14050004)+, Lower San Juan-Four Corners (14080201)+
15 Jadito Wash (15020014)+, Lower Little Colorado (15020016)+, Havasu-Mohave Lakes (15030101)+, Imperial Reservoir (15030104)+, Lower Colorado (15030107)+
16 Upper Bear (16010101)+, Central Bear (16010102)+, Curlew Valley (16020309)+
17 Chief Joseph (17020005), Okanogan (17020006), Upper Columbia-Entiat (17020010), Moses Coulee (17020012), Upper Crab (17020013), Banks Lake (17020014), Lower Crab (17020015), Upper Columbia-Priest Rapids (17020016), Upper Yakima (17030001), Lower Yakima, Washington (17030003), Gros Ventre (17040102)+, Portneuf (17040208)+, Lake Walcott (17040209)+, Raft (17040210)+, Goose (17040211)+, Upper Snake-Rock (17040212)+, Salmon Falls (17040213)+, Medicine Lodge (17040215)+, Big Lost (17040218)+, Big Wood (17040219)+, Camas (17040220)+, Little Wood (17040221)+, C. J. Idaho (17050101)+, Bruneau (17050102)+, Middle Snake-Succor (17050103)+, Upper Owyhee (17050104)+, South Fork Owyhee (17050105)+, Jordan (17050108)+, Lower Boise (17050114)+, North Fork Payette (17050123)+, Lower Snake (17060110), Upper Salmon (17060201)+, Middle Columbia-Lake Wallula (17070101), Walla Walla (17070102)
18 Butte Creek (18020158)+, South Fork Kern (18030002)+, Upper Kaweah (18030007)+, Tulare-Buena Vista Lakes (18030012)+, Middle San Joaquin-Lower (18040001)+, Middle San Joaquin-Lower (18040002)+, San Joaquin Delta (18040003)+, San Francisco Bay (18050004)+, Estrella (18060004)+, Salinas (18060005)+, Central Coastal (18060006)+, Santa Clara (18070102)+, San Pedro Channel Islands (18070107)+, San Jacinto (18070202)+, Santa Ana (18070203)+, Santa Margarita (18070302)+, Owens Lake (18090103)+, Antelope-Fremont Valleys (18090206)+, Coyote-Cuddeback Lakes (18090207)+, Mojave (18090208)+, Southern Mojave (18100100)+, Whitewater River (18100201)+, Carrizo Creek (18100202)+, San Felipe Creek (18100203)+, Salton Sea (18100204)+
PA PA-03 (PA-03)+*
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
Help
Basic Description: A bird (shrike).
General Description: Slightly smaller than American robin (TURDUS MIGRATORIUS); total length averages 23 cm; stout, hooked, all-dark bill; bluish-gray head and back; white or grayish-white underparts, very faintly barred in adults; broad black mask extending above eye and thinly across top of bill; gray to whitish rump; black tail with white tip; large white patches in the black wings; juveniles are paler and barred overall, with brownish-gray upperparts and buffy wing patches; males and females are similar in appearance (Miller 1931, NGS 1983, Fraser and Luukkonen 1986). Most nests are made of coarse twigs with a lining of plant material and animal hair (Fraser and Luukkonen 1986).
Diagnostic Characteristics: Differs from northern shrike (LANIUS EXCUBITOR) in having the base of the lower mandible black instead of pale, unbarred or barely barred underparts (adults), a shorter and less hooked bill, a darker head and back, and a more extensive black mask. Differs from the northern mockingbird (MIMUS POLYGLOTTOS) in having a black mask and a shorter, less curved bill.
Reproduction Comments: Male courtship behavior involves singing, flashing of white wing and tail markings, zigzagging flights and occasional chases of the female, and feeding of the female (Miller 1931, Bent 1950, Kridelbaugh 1982). Primarily monogamous, but polygny known (Yosef 1992, 1996). In Oklahoma, completed nests were found from mid-March through late June; nesting peaked in mid-April, with second nestings from late May to late June (Tyler 1992). In Missouri and Illinois, nesting peaked in late April, with a second peak in late May in Missouri (Tyler 1992). In Maryland, second nesting attempts occurred in June and July (Bartgis 1992). In Virginia, egg-laying extended from early April to mid-June (Byrd and Johnston 1991). Egg laying began in Colorado in early May. Egg dates for California and Florida are mainly February-July, March-June in Arizona and Texas. Single eggs are laid at intervals of one day. Clutch size usually averages 4-6. Incubation usually lasts 16-18 days (Lukkonen 1987, Tyler 1992), probably begins with the laying of the penultimate egg. Male feeds female during incubation. Young tended by both adults, fledge in about 17-20 days, independent in 36 days. Young generally stay concealed in foliage during the first few days out of the nest. About two weeks after leaving the nest, fledglings begins to capture food for themselves; they contunue to be fed by adults for about two more weeks (Luukkonen 1987, Novak 1989). By this time, adults and young begin foraging in areas away from the nesting territory (Novak 1989). In New York, family groups began to break up and disperse in August (Novak 1989). Renesting after nest failure is frequent in the Virginias and Maryland (Luukkonen 1987, Davidson 1988; Bartgis, pers. comm.), but second nesting attempts may be less common in the northern part of the range (Brooks and Temple 1986, Fruth 1988, Novak 1989). A third nesting attempt, usually unsuccessful, may follow an unsuccessful second nesting. Sometimes female leaves fledglings in care of male (Kridelbaugh 1982, Novak 1989); female may renest elsewhere with another male (Novak 1989, Haas and Sloane 1989).

Probability of survival from start of incubation to fledging ranged from 43% to 72% in several studies in different areas (see Tyler 1992). Nesting success tends to be fairly high (range was 50-74% in several studies in the eastern U.S.); generally at least 60% of nesting attempts fledge at least one young (Luukkonen 1987, Brooks 1988, Blumton et al. 1989, Novak 1989, Gawlik and Bildstein 1990, Bartgis 1992). Average number of young fledged per successful nest was 2.6, 3.5, 4.0, and 4.7 in Virginia, New York, Virginia, and South Carolina, respectively (Blumton et al. 1989, Novak 1989, Luukkonen 1987, and Gawlik and Bildstein 1990, respectively). Nest failure was attributed to cold wet weather and predation in New York (Novak 1989) and to predation, abandonment, and inadequate support of nests in Virginia (Luukkonen 1987). Nesting success tends to be better with dry, warm conditions than during cool, wet periods (Kridelbaugh 1982).

Ecology Comments: Territorial throughout the year. Size of territory may be about 10-16 ha in semidesert. In Florida, territory size varied from about 0.7 ha to 18 ha (Yosef and Grubb 1994). In New York, successful nesting pairs foraged over an area of 5.7-9.3 ha; the smallest area of active pasture in the nesting territory was about 5.5 ha (Novak 1989). Miller (1931) reported nesting territories of 4.4 to 16 ha. Kridelbaugh (1982) reported an average territory size of 4.6 ha in Missouri, with territory size increasing significantly after fledging. In Minnesota during the nesting season, shrikes foraged up to a quarter mile away from the nest (Brooks 1988). In general, nesting territories are smaller in areas with a greater amount of good quality habitat (Kridelbaugh 1982). In Virginia, juveniles established 2 ha to 36 ha (mean 19 ha) fall and winter territories, although use of woody habitats in inclement weather significantly enlarged the home range (Blumton et al. 1989). In Virginia, winter home ranges averaged 52 ha (Blumton et al. 1989).

Breeding and winter territories may or may not be separate. Males and females defend separate territories during the nonbreeding season.

In Virginia, juveniles 10-13 weeks old moved an average of 5.5 km from parents' territory to fall territory; predation by hawks and owls accounted for most fall and winter mortality, with the heaviest mortality in January when temperatures were coldest (Blumton et al. 1989). Suspected nest and fledgling predators in the northeastern North America include black rat snake (ELAPHE OBSOLETA), blue jay (CYANOCITTA CRISTATA), sharp-shinned hawk (ACCIPITER STRIATUS), domestic cat, and house wren (TROGLODYTES AEDON) (Luukkonen 1987, Novak 1989).

Habitat Type: Terrestrial
Non-Migrant: Y
Locally Migrant: Y
Long Distance Migrant: Y
Mobility and Migration Comments: Withdraws southward from northern half of breeding range for winter. Banding returns indicate that birds from as far north as Alberta and Quebec winter from southern Kansas, Missouri, and Virginia south to Alabama, Louisiana, and Texas (Fruth 1988). Shrikes in Wisconsin begin moving south in August. In Oklahoma and Missouri, begins to arrive and set up breeding teritories in mid-February (Tyler 1992). Returns to nesting areas in New York in mid- to late April (Novak 1989). Shrikes breeding in the Virginias and Maryland frequently are resident, but there appears to be some southward movement. Shrikes that formerly bred in New England apparently followed a predominantly coastal migration route (Milburn 1981). Nonmigratory in much of California, especially in southern and central coastal regions (Matthews and Moseley 1990).
Terrestrial Habitat(s): Cropland/hedgerow, Desert, Grassland/herbaceous, Old field, Savanna, Shrubland/chaparral
Habitat Comments: BREEDING: Open country with scattered trees and shrubs, savanna, desert scrub (southwestern U.S.), and, occasionally, open woodland; often perches on poles, wires or fenceposts (Tropical to Temperate zones) (AOU 1983). Suitable hunting perches are an important part of the habitat (Yosef and Grubb 1994).

For nesting, prefers shortgrass pastures in western Canada, Texas (Telfer 1992), and many other areas (Luukkonen 1987, Novak 1989, Gawlik and Bildstein 1990, Bartgis 1992). In Missouri, pasture land surrounded 67% of 60 nests (Kridelbaugh 1982). In New York, occupied nest sites were in pasture areas with less than 20% woody cover (Novak 1989). However, others have found no preference for short-grass areas (e.g., see Chavez-Ramirez et al. 1994). Historically, orchards seemingly were used with some frequency (see Novak 1989). In the upper Midwest, Brooks (1988) found that nestling growth rate, nesting success, and fledgling success were positively correlated with percentage of home range coverage in grassland. In Virginia, pairs nesting in active pastures produced twice as many young as did those in other habitats (Luukkonen 1987).

Nests in shrubs or small trees (deciduous or coniferous, e.g., in eastern North America, JUNIPERUS VIRGINIANA, CRATAEGUS sp., MACLURA POMIFERA, ROSA MULTIFLORA). In northern latitudes, nest sites include spruce and fir trees (Bent 1950, Brooks 1988). In some areas, vine-covered plants are preferred (Luukkonen 1987, Novak 1989). In Missouri, nests in multiflora rose were less successful than were those in trees, perhaps because the nests in roses were lower and poorly supported (Kridelbaugh 1982). In South Carolina, nests in JUNIPERUS fledged a larger number of young than did nests in other sites (5.0 young per successful nest vs. 4.0) (Gawlik and Bildstein 1990). Nests generally are 1.5-3 m above ground, in a crotch or on top of an old nest. In New York, nests were typically 1.5-2.5 m high in trees 4-5 m tall, and usually they were more than a meter back from the outside of the tree (Novak 1989). In Virginia, average nest height was 2.6 m in trees averaging 6.8 m tall; nest height was higher (mean 5.5 m) in second and third nesting attempts (Luukkonen 1987). Nests often in isolated woody plants but also commonly along fencelines or hedgerows (Brooks 1988, Luukkonen 1987), in an open area in a wooded area or in open country. Tends to nest in areas with several potential suitable nesting trees/shrubs (Brooks 1988).

Sometimes nests in the same site in successive years, but return rates generally are low; males are most likely to reoccupy previous breeding territories (Kridelbaugh 1982, Luukkonen 1987, Brooks 1988, Bartgis 1989, Haas and Sloane 1989). In Minnesota and Virginia, respectively, 50% and 30% of breeding territories were not occupied the following year; in Virginia, reoccupation was more frequent in active pasture than in pastures allowed to grow tall (Brooks 1988, Luukonen 1987). Causes of variation in rates of territory reoccupancy have been discussed but available evidence is inconclusive and may differ in different areas (cf. Brooks 1988, Luukkonen 1987, Novak 1989, Haas and Sloane 1989). For a particular pair during a single season, nesting attempts after the first one generally are close to the first site (mean 90 m in Virginia) (Luukkonen 1987). Both sexes are involved in nest site selection and nest construction (Kridelbaugh 1982).

NON-BREEDING: During periods of cold with snow cover, sometimes moves into woodlots (Byrd and Johnston 1991). In winter in Virginia, many move from pastures to shrub and open forest habitats during periods of cold, wet weather (Blumton et al. 1989).

Adult Food Habits: Carnivore, Invertivore
Immature Food Habits: Carnivore, Invertivore
Food Comments: Feeds primarily on large insects (especially beetles and orthopterans), also other invertebrates, small birds, lizards, frogs, and rodents; sometimes scavenges (Fraser and Luukkonen 1986). Diet varies with season and location; in parts of the range, most of the food eaten in winter may be vertebrates, which comprise only a small part of the diet in California. In California, the summer diet comprises mainly insects (Terres 1980). Captures prey usually via a short flight from a perch; sometimes hovers kestrel-like or walks when foraging (Bent 1950, Luukkonen 1987). Sometimes impales food items on a plant thorn or on barbed wire (Fraser and Luukkonen 1986); such items may be eaten later or fed to young (Applegate 1977).
Adult Phenology: Diurnal
Immature Phenology: Diurnal
Length: 23 centimeters
Weight: 47 grams
Economic Attributes Not yet assessed
Help
Management Summary
Help
Stewardship Overview: In the north-central and northeastern U.S. and adjacent Canada, maintenance of suitable habitat away from roads, encouragement of farming practices that retain or establish hedgerows and permanent pastures, and minimization of pesticide use in shrike habitat may be beneficial.
Restoration Potential: Since reproductive success rates are relatively high for shrikes, there seems to be excellent potential for the species to significantly expand its existing population if the cause or causes of the decline can be identified and eliminated. Although there has been substantial loss of suitable habitat in the Northeast and perhaps elsewhere, there appears to be enough remaining unoccupied suitable habitat that existing areas can accommodate a larger population than that which currently exists. However, trends in habitat loss are likely to continue and may ultimately limit the possibility of any long-term expansion. Release of captive-bred individuals eventually may be a useful management tool (Bartgis 1992). See Cade (1992) for information on successful captive breeding.
Management Requirements: Until the cause of the decline can be determined, maintaining suitable nesting and wintering habitat in areas of regular shrike activity is worthwhile. Maintaining suitable nesting habitat in the Northeast will require keeping suitable landscape features in active pastures. Suitable nest tree criteria are described under Habitat. Kridelbaugh (1982) recommended discouraging multiflora rose (unsupported bushes, not those that climb up trees) in a breeding area since they provide poor nest support. Potential perch sites are also important. In Virginia, pastures with many potential perches had higher productivity (Luukkonen 1987). In New York, Novak (1989) reported tall isolated shrubs were typically present near nest sites at a density of three or more shrubs per hectare. Removal of fences, hedgerows, and woody vegetation eliminates potential perches and lowers habitat quality (Luukkonen 1987). Adding hunting perches can enhance habitat and can also increase the size of a local population (territory size may be decreased and thus more territories can be accommodated into a given area) (Yosef and Grubb 1994).

The timing of habitat selection could cause shrikes to select marginal habitat. For example, a hayfield selected in early spring could appear to be similar to an active pasture, but it would be quite different once vegetation begins to grow (Luukkonen 1987). However, in the states where shrikes are resident, birds have the opportunity to continually evaluate habitat. Changes in location, timing and intensity of grazing could still decrease the predictability of habitat suitability (Luukkonen 1987). Consequently, active grazing regimes should be maintained at the nest site, or if stock use is rotated between fields, there should be adjacent fields so that foraging activity will require minimal changes.

Herbaceous vegetation that is allowed to grow too tall or woody vegetation that becomes too dense eliminates the area as potential foraging habitat. Thorny shrubs, barbed-wire fences, and other objects suitable for impaling prey are also significant features of habitat that should be maintained. For specific sites in the Northeast where it is important to maintain a given shrike territory, landscape features that could attract activity to roadways, such as perches and potential nesting trees near highways, might be eliminated if similar features occur away from roadways. Such management could reduce mortality resulting from collisions with automobiles. However, for the northcentral states, Hands et al. (1989) recommended maintaining perches along a road since shrikes frequently use roadsides. If highway mortality at a site has severe impacts on local nesting success, speed bumps and traffic enforcement may be required. Chavez-Ramirez et al. (1994) cautioned that management practices developed in agricultural systems may not be appropriate in natural grasslands.

Hands et al. (1989) recommended restricting pesticide use in shrike habitat in order to avoid depressing the abundance of potential prey items. Also, for local situations where predation is identified as a problem, predator management may be necessary once nest and fledgling predators are identified (Hands et al. 1989).

Monitoring Requirements: The fact that BBS data indicate significant declines in all regions of the country, as well as extreme declines in northern regions, suggests that a periodic nationwide monitoring program would be prudent. The population in the northeastern and north-central U.S. has become small enough, particularly outside Virginia, that the loss of any breeding pair may be significant. Consequently, tracking nesting locations and nesting attempts in all states is probably worthwhile. This may identify site-specific problems that can be ameliorated and help contribute to understanding causes of the decline. Monitoring is especially difficult in states with a great deal of unoccupied suitable habitat. BBS and Christmas Bird Counts will continue to be valuable tools for monitoring this species rangewide, but more concentrated efforts are needed in states with very low populations (Bartgis 1992). In Maryland, New York, West Virginia, Minnesota, Wisconsin and Michigan where there are few shrikes, nesting territories should be monitored every year. This may alert biologists to potentially avoidable losses in habitat quality for each occupied territory, and in these states any avoidable losses should be prevented. In Virginia, annual monitoring of each territory may not be practical. Hands et al. (1989) suggested monitoring territories in the northcentral states every three years.

Monitoring efforts should be timed to coincide with when the birds are most detectable. Copulation and courtship behavior occur soon after shrikes set up breeding territories and birds are more difficult to find during this period (Novak 1989). After incubation begins, males are typically found hunting and carrying food to the female, making it relatively easy to locate nests at this time.

Announcements in ornithological society newsletters and posters placed in agricultural districts can provide leads on local populations, and volunteers familiar with local areas have been effectively used to locate nests (Luukkonen 1987, Novak 1989). Because farmland in the Northeast usually has many roads, surveys from vehicles are often productive and effective. Evaluation of the practicality of vehicle surveys in the Northcentral region is necessary.

Because nesting success appears to be high, close monitoring of nesting effort may be of little value unless it is done in context of a more comprehensive demographic study. Nevertheless, certain site-specific data that can be determined for a nest site can be used for preserve design purposes and during discussions with landowners. These items include mapping and describing the adult foraging area, fledgling use area, nest tree selection, and perch selection. Kridelbaugh (1982) found that two to three hours of observation was sufficient to determine nesting territory size. Miller (1931) thought that a half-hour or less spent observing the pair was sufficient to adequately map a shrike's territory.

Changes in gross habitat characteristics, such as active pasture being abandoned or tilled or perches being cut down, should be tracked from one year to the next. Nest predation rates in roadside habitats should also be monitored and compared to more isolated nest sites. Determination of the proportion of nesting attempts in roadside versus isolated sites also would be useful in deciphering reasons for the species' decline.

Fledglings should be sought to determine if nesting attempts successfully produce young. The site should also be revisited through the summer to determine if any additional nesting attempts occur and if the shrikes shift foraging or nesting territory areas. Monitoring reproductive success does not typically require handling the birds. Spotting scopes are usually suitable for observing younger fledglings while more mobile adults and older fledglings are more readily observed with binoculars (Novak 1989). Development of nestlings can be observed with permanently placed mirrors observed with a spotting scope, as long as significant disturbance to the nest cover does not occur (Lohrer 1974). To minimize such disturbance, some workers check nests with mirrors on poles once or twice during each part of the nesting process (Novak 1989) or about once a week (Luukkonen 1987). To prevent premature fledging, mirrors should not be placed near the nest when nestlings are 17-18 days old (Luukkonen 1987).

Bal-Chatri traps and Potter traps are usually used to catch shrikes (Brooks 1988, Novak 1989), although Lohrer (1974) found that two-cell wire box traps may stress the birds less. Typical bait includes field and white lab mice and zebra finches (Brooks 1988, Lohrer 1974, Novak 1989). At a distance, wing tags are more easily observed than color leg bands. However, tagged shrikes have been observed entangled in vegetation with injury and mortality occurring as a result (Lohrer 1974). Brooks (1988) and Luukkonen (1987) banded nestlings before they fledged. None of these researchers or Kridelbaugh (1982) reported any observed injuries from using aluminum USFWS or colored leg bands. Mortality rates and causes and seasonal dispersal could be determined by using color-banding and radio telemetry (Hands et al. 1989). There may be too few shrikes left in New York for such efforts to be meaningful. Some radio telemetry and color-banding/flagging has been done in Virginia (Blumton et al. 1989).

Management Research Needs: Determining the cause(s) of the decline remains the major emphasis of most research activities. In the northeastern and north-central states, studies of reproductive success have not provided an answer. Studying the causes of mortality could prove valuable. For example, is automobile mortality highest for migratory birds because these birds encounter a greater number of areas with which they are unfamiliar? Is automobile caused mortality higher for inexperienced juveniles than for adults? Are BBS trends correlated with geographic trends in road density? Are predation rates always much higher along roads, and are shrikes tending to use roadside habitat more and more often? Though pesticides have not been linked to lowered reproductive success, additional studies of other potential pesticide impacts on shrikes should also be conducted.

Although the decline in potential breeding habitat acreage in the Northeast is well documented, the potential impact of habitat fragmentation remains to be addressed. One approach would involve comparing size and degree of isolation for blocks of suitable habitat among areas which have: a stable population; a declining population; or an extirpated population. Several researchers expressed concern that declines in winter habitat quality or quantity may be affecting migrant populations. Tracking foraging success and overall vigor of resident versus migrant birds in the winter may provide some answers (Bartgis 1992).

Biological Research Needs: Determing the causes of its population decline should remain the major emphasis of most research activities for this species (Yosef, 1996).
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
Help
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
Help
Authors/Contributors
Help
NatureServe Conservation Status Factors Edition Date: 06Mar2014
NatureServe Conservation Status Factors Author: Judith Soule. Partially revised by G. Hammerson. Partially revised 2014-03-06 by Jue, Sally S.
Management Information Edition Date: 06May1992
Management Information Edition Author: BARTGIS, R.; REVISIONS BY J. SOULE, G. HAMMERSON, AND D.W. MEHLMAN
Management Information Acknowledgments: Parts of this abstract were originally published by the U.S. Fish and Wildlife Service in Schneider and Pence (1992). Funding to prepare this work was provided to The Nature Conservancy by the U.S. Fish and Wildlife Service and the U.S. Forest Service. Special thanks are extended to Kathy Schneider of the New York Natural Heritage Program and Larry Master of The Nature Conservancy for editorial and organizational guidance. Many people provided information that made this project possible. BBS data were provided by Sam Droege of the U.S. Fish and Wildlife Service, Office of Migratory Bird Management. Breeding bird atlas information was provided and/or reviewed by: Al Hutchinson (Maine), Jim Baird (Massachusetts), Louis Bevier (Connecticut), Dan Brauning (Pennsylvania), Rick Enser (Rhode Island), Edie Hentcy, Carol Foss, and Sally Sutcliff (New Hampshire), Sally Laughlin (Vermont), Dorothy Hughes (New Jersey), Walt Sabin, Robert Miller, and John Ozard (New York), Sue Ridd and Becky Wadja (Virginia), Craig Stihler and Art Buckalew (West Virginia), Glenn Therres (Maryland), and Richard West (Delaware). Additional state-specific information that contributed significantly to this report was supplied by state nongame and fish and wildlife agencies and The Nature Conservancy's network of state Natural Heritage Programs.
Element Ecology & Life History Edition Date: 03May1995
Element Ecology & Life History Author(s): SOULE, J., AND G. HAMMERSON

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

References
Help
  • Yosef, Reuven. 1996. Loggerhead Shrike (Lanius ludovicianus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu.bnaproxy.birds.cornell.edu/bna/species/231

    doi:10.2173/bna.231


  • Alabama Breeding Bird Atlas 2000-2006 Homepage. 2009. T.M. Haggerty (editor), Alabama Ornithological Society. Available at http://www.una.edu/faculty/thaggerty/BBA%20website/Index.htm.

  • 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/.

  • Anderson, W. C., and R. E. Duzan. 1978. DDE residues and eggshell thinning in loggerhead shrikes. Wilson Bull. 90:215-220.

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

  • Andrle, Robert F. and Janet R. Carroll, editors. 1988. The atlas of breeding birds in New York State. Cornell University Press. 551 pp.

  • Applegate, R. D. 1977. Possible ecological role of food caches of loggerhead shrike. Auk 94:391-392.

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

  • Austen, M.J.W., M.D. Cadman and R.D. James. 1994. Ontario Birds at Risk: Status and Conservation Needs. Federation of Ontario Naturalists, Don Mills, and Long Point Bird Observatory, Port Rowan, Ontario. 165 pp.

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

  • Bailey, A. M. and R. J. Niedrach. 1965. Birds of Colorado. Denver Museum of Natural History. 2 vols. 895 pp.

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

  • Bartgis, R. 1992. Loggerhead shrike, LANIUS LUDOVICIANUS. Pages 281-297 in K. J. Schneider and D. M. Pence, editors. Migratory nongame birds of management concern in the Northeast. U.S. Fish and Wildlife Service, Newton Corner, Massachusetts. 400 pp.

  • Bartgis, R. L. 1989. Site surveys for rare plants and animals in eastern West Virginia. Unpubl. report, The Nature Conservancy, Boston, Massachusetts.

  • Beaulieu, H. 1992. Liste des espèces de la faune vertébrée susceptibles d'être désignées menacées ou vulnérables. Ministère du Loisir, de la Chasse et de la Pêche. 107 p.

  • Beauvais, G. P. and W. Fertig. 2000. Status report for rare vertebrates and plants in Laramie County, Wyoming. Prepared by the Wyoming Natural Diversity Database for the Wyoming Cooperative Fish and Wildlife Research Unit, USDI Fish and Wildlife Service, and Laramie County Wyoming.

  • Bent, A.C. 1950. Life histories of North American wagtails, shrikes, vireos, and their allies. U.S. Natl. Mus. Bull. 197. Washington, D.C.

  • Bighorn National Forest. 1996. Endangered and Sensitive animal species of the Bighorn National Forest. Unpublished draft report on file at Bighorn NF Supervisor's Office, Sheridan, Wyoming.

  • BirdLife International. (2013-2014). IUCN Red List for birds. Downloaded from http://www.birdlife.org on various dates in 2013 and 2014. http://www.birdlife.org/

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

  • Blumton, A. K., J. D. Fraser, and K. Terwilliger. 1989. Loggerhead shrike survey and census. Pages 116-118 in Virginia nongame and endangered wildlife investigative annual report, July 1, 1988 through June 30, 1989. Virginia Department of Game and Inland Fisheries, Richmond, Virginia.

  • Brooks, B. L. 1988. The breeding distribution, population dynamics, and habitat availability and suitability of an Upper Midwest Loggerhead Shrike population. M. S. Thesis, University of Wisconsin, Madison, Wisconsin. 58 pp.

  • Brooks, B. L. 1988. The breeding distribution, population dynamics, and habitat availability of an upper Midwest loggerhead shrike population. Master's thesis, Univ. Wisconsin, Madison.

  • Brooks, B. L. and S. A. Temple. 1990a. Habitat availability and suitability for loggerhead shrikes in the Upper Midwest. Am. Midl. Nat. 123: 75-83.

  • Brooks, B. L., and S. A. Temple. 1986. Progress Report on a study of the breeding habitat, distribution, and reproductive success of the Loggerhead Shrike in Minnesota. Unpublished report submitted to the Minnesota chapter of the Nature Conservancy and Minnesota Department of Natural Resources. September 19, 1986.

  • Brooks, B. L., and S. A. Temple. 1990. Dynamics of a Loggerhead Shrike population in Minnesota. Wilson Bulletin 102(3):441-450.

  • Brooks, B. L., and S. A. Temple. 1990b. Dynamics of a loggerhead shrike population in Minnesota. Wilson Bull. 102:441-450.

  • Brooks, B.L. and S.A. Temple. 1990 Habitat availability and suitability for loggerhead shrikes in the upper Midwest. Amer. Midl. Nat. 123:75-83.

  • Brooks, B.L. and S.A. Temple. 1990. Dynamics of a loggerhead shrike population in Minnesota. Wilson Bull. 102(3):441-450.

  • Brooks, M. 1999. Effects of Protective Fencing on Birds, Lizards, and Black-Tailed Hares in the Western Mojave Desert. Environmental Management. 23:387-400.

  • Bureau of Land Management. Life History Summaries.

  • Burton, Ken. 1990. 1988-90 Loggerhead Shrike Survey. Maps.

  • Burton, Kenneth M. 1988. An Investigation of Population Status and Breeding Biology of the Loggerhead Shrike (Lanius ludovicianus) in Indiana. Submitted to Indiana Department of Natural Resources, Division of Fish and Wildlife, Nongame and Endangered Wildlife Program. 25 pp.

  • Burton, Kenneth. 1989. Loggerhead Shrike Update. 67(1) Ind. Aud. Q. 41-42.

  • Burton, Kenneth. 1990. Loggerhead Shrike Update. 68(1) Ind. Aud. Q. 57-58.

  • Busbee, E. L. 1977. The effects of dieldrin on the behavior of young loggerhead shrikes. Auk 94:28-35.

  • Byrd, M. A., and D. W. Johnston. 1991. Birds. Pages 477-537 in K. Terwilliger, coordinator. Virginia's endangered species: proceedings of a symposium. McDonald and Woodward Publ. Co., Blacksburg, Virginia.

  • CADE, T.J. AND C.P. WOODS. 1997. CHANGES IN DISTRIBUTION AND ABUNDANCE OF THE LOGGERHEAD SHRIKE. CONS. BIOL. 11(1):21-31.

  • CHABOT, Amy, TITMAN, Rodger et BIRD, David. 1993. Choix des habitats de la pie-grièche migratrice en Ontario et au Québec. Rapport final du 1er juin 93. Centre de Recherche et de Conversation des Oiseaux, Université McGill. 7 p.

  • COLLISTER, D.M. AND R.G. FISHER. 1995. TRAPPING TECHNIQUES FOR LOGGERHEAD SHRIKES. WILDL. SOC. BULL. 23(1):88-91.

  • COSSARO. 2014. Ontario Species at Risk Evaluation Report for Loggerhead Shrike (Lanius ludovicianus). December 2014 (final). 17pp.

  • Cade, T. J. 1992. Hand-reared loggerhead shrikes breed in captivity. Condor 94:1027-1029.

  • Cade, Tom J. and Christopher P. Woods. 1997. Changes in Distribution and Abundance of the Loggerhead Shrike. Conservation Biology. Vol 11(1):21-31.

  • Cadman, M. 1984. Atlassing and the Loggerhead Shrike (Lanius ludovicianus). Ontario Birds 2(1): 40-41.

  • Cadman, M. 1985. Status report on the Loggerhead Shrike in Canada (Lanius ludovicianus). COSEWIC report. 95 pp.

  • Cadman, M. D. 1991. Updated status report on the Loggerhead Shrike (eastern population) LANIUS LUDOVICIANUS MIGRANS, in Canada. Committee on the Status of Endangered Wildlife in Canada (COSEWIC). 26 pp.

  • Cadman, M.D. 1986. Status report on the loggerhead shrike LANIUS LUDOVICIANUS. Committee on the Status of Endangered Wildlife in Canada (COSEWIC). 95 pp.

  • Cadman, M.D. 1990. Update Status Report on the Loggerhead Shrike (Lanius ludovicianus) in Ontario. 30 pp including 2 Appendices.

  • Cadman, M.D., P.F.J. Eagles and F.M. Helleiner (eds.) 1987. Atlas of the Breeding Birds of Ontario. Federation of Ontario Naturalists and Long Point Bird Observatory. University of Waterloo Press, Waterloo, Ontario. 617 pp.

  • Campbell, Jim, and Midge Lechner. 1995. Endangered, Threatened, and Special Concern Species. Observation Notes. 4 pp.

  • Canadian Wildlife Service. 1993. Loggerhead Shrike: Hinterland Who's Who. Environment Canada, Canadian Wildlife Service, Ottawa. 3 pp.

  • Cannings, S. 2001. EO Specifications for Loggerhead Shrike (Lanius ludovicianus). NatureServe, Unpublished. 1 pp.

  • Carter, M., G. Fenwick, C. Hunter, D. Pashley, D. Petit, J. Price, and J. Trapp. 1996. Watchlist 1996: For the future. Field Notes 50(3):238-240.

  • Chabot, A.A. 1994. Habitat selection and reproductive biology of the Loggerhead Shrike in eastern Ontario and Quebec. A thesis submitted to the Faculty of Graduate Studies and Research of McGill University, Department of Natural Resource Sciences, McGill University, Montreal. 97 pp.

  • Chavez-Ramirez, F., et al. 1994. Effects of habitat structure on patch use by loggerhead shrikes wintering in a natural grassland. Condor 96:228-231.

  • Clarke, C.K. 1897. Notes on some Ontario birds. Auk 14:410-411..

  • Cuddy, D. 1994. Loggerhead Shrike sighting records. Unpublished, memorandum dated June 8, 1994. 2 pp.

  • Cuddy, D. 1999. Loggerhead Shrike Recovery Team Meeting: Toronto Zoo -- October 25, 1999. Unpublished minutes. 4 pp.

  • Cuddy, D.G., A.A. Chabot and C.J. Grooms. 1993. Loggerhead Shrike Recovery Activities, Ontario, 1993, Habitat Mapping (Draft Report). Unpublished. 9 pp.

  • Cyr, A. et J. Larivée. 1995. Atlas saisonnier des oiseaux du Québec. Les Presses de l'Université de Sherbrooke et La Société de Loisir Ornithologique de l'Estrie, inc. Sherbrooke 711p.

  • Davidson, L. M. 1988. Loggerhead shrike nest in Washington County, MD. Maryland Birdlife 44:3-5.

  • De Geus, D.W. and L.B. Best. 1989. An evaluation of causes for decline of loggerhead shrikes in Iowa. Research Report Submitted to Iowa DNR Nongame Program. 16pp.

  • DeGeus, D. W. 1990. Productivity and habitat preferences of loggerhead shrikes inhabiting roadsides in a midwestern agroenvironment. Iowa State University, Ames, Iowa. MS thesis.

  • DeGeus, D. W. 1991. Brown-headed cowbirds parasitize loggerhead shrikes: first records for family Laniidae. Wilson Bulletin 101(3):504-6.

  • 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.

  • Dorn, J. L. and R. D. Dorn. 1999. Wyoming birds. Second edition. Mountain West Publishing. Cheyenne, Wyoming.

  • Dorn, Jane L. and R.D. Dorn. 1990. Wyoming Birds. Mountain West Publishing, Cheyenne.

  • 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.

  • Dyer, M. and M.D. Cadman. 1991. Loggerhead Shrike habitat survey - Napanee District. A Report to the Ontario Ministry of Natural Resources, Napanee District. 17 + app pp.

  • E.S. TELFER. 1990. National recovery plan for the Loggerhead Shrike. Canadian Wildlife Service. Edmondton, Alberta V + 28p.

  • Ehrlich, P. R., D. S. Dobkin, and D. Wheye. 1988. The Birder's Handbook: A Field Guide to the Natural History of North American Birds. Simon and Shuster, Inc., New York. xxx + 785 pp.

  • Ehrlich, P. R., D. S. Dobkin, and D. Wheye. 1988. The birder's handbook: a field guide to the natural history of North American birds. Simon and Shuster, Inc., New York. xxx + 785 pp.

  • Ehrlich, P. R., D. S. Dobkin, and D. Wheye. 1992. Birds in Jeopardy: the Imperiled and Extinct Birds of the United States and Canada, Including Hawaii and Puerto Rico. Stanford University Press, Stanford, California. 259 pp.

  • Eliason, B. 1996. Statewide survey and habitat protection for the loggerhead shrike in Minnesota. Final Report submitted to the Partners for Wildlife Program, U. S. Fish and Wildlife Service. 7 pp. +.

  • Etter, M. A. 1995. 1995 Minnesota Loggerhead Shrike survey. Report submitted to the Nongame Wildlife Program, Minnesota Department of Natural Resources. 14 pp +.

  • Finch, D.M. 1992. Threatened, endangered, and vulnerable species of terrestrial vertebrates in the Rocky Mountain Region. General Technical Report RM-215. USDA, Forest Service, Rocky Mountain Forest and Range Experiment Station, Ft. Collins CO. 38 p.

  • Fitchel, C. 1988. 1988 status survey of the loggerhead shrike in Vermont. Unpubl. report, Agency of Natural Resources, Waterbury, Vermont.

  • Florida Fish and Wildlife Conservation Commission2003, January 6. Florida's breeding bird atlas: A collaborative study of Florida's birdlife. http://legacy.myfwc.com/bba/species.asp.
     

  • Fraser, J. D., and D. R. Luukkonen. 1986. The loggerhead shrike. Pages 933-941 in R. L. DiSilvestro, editor. Audubon Wildlife Report 1986. Academic Press, New York.

  • Fruth, K. J. 1988. The Wisconsin Loggerhead Shrike Recovery Plan. Wisconsin Endangered Resources Report 38. Bureau of Endangered Resources, Wisconsin Department of Natural Resources, Madison, Wisconsin.

  • Gauthier, J. et Y. Aubry (sous la direction de) 1995. Les oiseaux nicheurs du Québec : Atlas des oiseaux nicheurs du Québec méridional. Association québécoise des groupes d'ornithologues, Société québécoise de protection des oiseaux, Service canadien de l

  • Gawlik, D. E., and K. L. Bildstein. 1990. Reproductive success and nesting habitat of loggerhead shrikes in north-central South Carolina. Wilson Bull. 102:37-48.

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

  • Graber, R.R., J.W. Graber, and E.L. Kirk. 1973. Illinois birds: Laniidae. Ill. Nat. Hist. Surv. Biol. Notes. No. 83. 18pp.

  • Greenlaw, Jon S., Bill Pranty, and Reed Bowman.  2014.  Robertson and Woolfenden Florida Bird Species:  An Annotated List.  Special Publication No. 8, Florida Ornithological Society, Gainesville, FL.
     

  • Grooms, C. 1999. Loggerhead Shrike Recovery Activities Field Work 1999 - Draft. Unpublished draft report to the Canadian Wildlife Service and the Eastern Loggerhead Shrike Recovery Team. 12 pp.

  • Haas, C. A., and S. A. Sloane. 1989. Low return rates of migratory Loggerhead Shrikes: winter mortality or low site fidelity? Wilson Bulletin 101(3):458-60.

  • Hands, H. M., R. D. Drobney, and M. R. Ryan. 1989. Status of the loggerhead shrike in the northcentral United States. Missouri Coop. Fish Wildl. Res. Unit Rep. 15 pp.

  • Hanrahan, C. n.d. The Loggerhead Shrike: status report for the Ottawa District. Trail & Landscape 21(3): 154-168.

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

  • Haw, James. 1994. Summer Observations of Endangered Bird Species.

  • Herkert, J. R., editor. 1992. Endangered and threatened species of Illinois: status and distribution. Vol. 2: Animals. Illinois Endangered Species Protection Board. iv + 142 pp.

  • Hershberger, W. 1989. Loggerhead shrike (LANIUS LUDOVICIANUS) survey: spring 1989 for the Washington and Frederick counties of Maryland. Unpubl. report, Maryland Natural Heritage Program, Annapolis, Maryland.

  • Hershberger, W. 1989. Loggerhead shrike survey 1990 (LANIUS LUDOVICIANUS), Frederick and Washington counties of Maryland. Unpubl. report, Maryland Natural Heritage Program, Annapolis, Maryland.

  • 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.

  • JOHNS, B., E. TELFER, M, CADMAN, D. BIRD, R. BJORGE, K., De SMET, W. HARRIS, D. HJERTAAS, P. LAPORTE, R. PITTAWAY. 1994. Plan national de rétablissement de la pie-grièche migratrice. Rapport # 7. Comité de rétablissement des espèces canadiennes en péril.

  • James, R.D. 2000. Update COSEWIC Status Report on Eastern Loggerhead Shrike (Lanius excubitor migrans) in Canada. Unpublished report prepared for the Committee on the Status of Endangered Wildlife in Canada. 10 pp.

  • Johns, B., E. Telfer, M. Cadman, D. Bird, R. Bjorge, K. De Smet, W. Harris, D. Hjertaas, P. Laporte, and R. Pittaway. 1994. National recovery plan for the Loggerhead Shrike. Report No. 7. Ottawa: Recovery of Nationally Endangered Wildlife Committee, 32 pp

  • Keinath, D.A. and C. Schneider. 2005. Species assessment for Loggerhead Shrike (Lanius ludovicianus) in Wyoming. Report prepared for USDI Wyoming Bureau of Land Management by Wyoming Natural Diversity Database-University of Wyoming, Laramie, Wyoming.

  • Kibbe, D. P. 1985. Loggerhead shrike. Pages 260-261 in S. B. Laughlin and D. P. Kibbe, editors. The atlas of breeding birds of Vermont. Univ. Press of New England, Hanover, New Hampshire.

  • Kingery, H. E., editor. 1998. Colorado Breeding Bird Atlas. Colorado Bird Atlas Partnership and Colorado Division of Wildlife, Denver, CO. 636 pp.

  • Kridelbaugh, A. L. 1981. Population trend, breeding and wintering distribution of loggerhead shriked (Lanius ludovicianus) in Missouri. Transactions, Missouri Academy of Science 111-119.

  • Kridelbaugh, A. L. 1982. An ecological study of loggerhead shrikes in central Missouri. Master's thesis, Univ. Missouri, Columbia.

  • Kridelbaugh, A. L. 1982. Improved trapping methods for loggerhead shrikes. North American Bird Bander 7(2):50-51.

  • Kridelbaugh, A. L. 1983. Nesting ecology of loggerhead shrike in central Missouri. The Wilson Bulletin 95(2): 303-308.

  • Laporte P. 2002. Pie-grièche migratrice. QuébecOiseaux, vol. 14. Hors série 2002. p. 21-23.

  • Lemieux, C. 1992. Brief Summary: The Loggerhead Shrike (Lanius ludovicianus). n/a. 13 pp.

  • Levine, E. 1998. Bull's birds of New York State. Comstock Publishing Associates, Ithaca, NY.

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

  • Lohrer, F. E. 1974. Some techniques used in a field study of loggerhead shrikes. Bird Banding 45:361-362.

  • Long Point Bird Observatory. 1997. A landowner's resource guide: endangered Loggerhead Shrikes and other grassland birds. Long Point Bird Observatory. 10 pp.

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

  • Luukkonen, D. R. 1987. Loggerhead shrike status and breeding ecology in Virginia. Master's thesis, Virginia Polytechnic Institute and Sate University, Blacksburg.

  • Madrone, Brooke. 1992. Factors in the Decline of the Loggerheaded Shrike. College of Forest Resources.

  • Matthews, J.R. and C.J. Moseley (eds.). 1990. The Official World Wildlife Fund Guide to Endangered Species of North America. Volume 1. Plants, Mammals. xxiii + pp 1-560 + 33 pp. appendix + 6 pp. glossary + 16 pp. index. Volume 2. Birds, Reptiles, Amphibians, Fishes, Mussels, Crustaceans, Snails, Insects, and Arachnids. xiii + pp. 561-1180. Beacham Publications, Inc., Washington, D.C.

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

  • McGee, M., D.A. Keinath, and G.P. Beauvais. 2002. Survey for rare vertebrates in the Pinedale Field Office of the USDI Bureau of Land Management (Wyoming). Unpublished report prepared for USDI Bureau of Land Management - Wyoming State Office by the Wyoming Natural Diversity Database - University of Wyoming, Laramie, Wyoming.

  • Merrill, E.H., T.W. Kohley, and M.E. Herdendorf. 1996. Wyoming Gap Analysis terrestrial vertebrate species map atlas. Wyoming Cooperative Fish and Wildlife Unit, University of Wyoming, Laramie WY. 982 pp. in 2 volumes.

  • Milburn, T. 1981. STATUS & DISTRIBUTION OF THE LOGGERHEAD SHRIKE, LANIUS LUDOVICIANUS IN THE NORTHEASTERN U.S. UNPUB- LISHED REPORT SUBMITTED TO THE USDI/FWS OFFICE OF ENDANGERED SPECIES. 77 PP.

  • Miller, A. H. 1931. Systematic revision and natural history of the American shrikes (LANIUS). Univ. California Publ. Zool. 38:11-242.

  • Mills, S. and M. Neighbours. 1995. Intensive data gathering project (fine-filter analysis) for occurrences of rare, threatened, endangered and sensitive species in sections M331H and M331I, north central highlands and northern parks and ranges, in Wyoming. Unpublished report prepared for Medicine Bow National Forest by the Wyoming Natural Diversity Database, Laramie, WY. 294 pp.

  • Mirarchi, R. E., M. A. Bailey, T. M. Haggerty, and T. L. Best, editors. 2004. Alabama wildlife. Volume 3. Imperiled amphibians, reptiles, birds, and mammals. The University of Alabama Press, Tuscaloosa, Alabama. 225 pages.

  • 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.

  • 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.

  • Morrison, M. L. 1981a. Population trends of the Loggerhead Shrike in the United States. Am. Birds 35(4): 754-757.

  • Morrison, M. L. 1981a. Population trends of the Loggerhead Shrike in the United States. American Birds 35(4):754-7.

  • National Audubon Society.  2014.  View all Species.  Website accessible at http://birds.audubon.org/species.  Accessed on various dates in 2014.

  • National Geographic Society (NGS). 1983. Field guide to the birds of North America. National Geographic Society, Washington, DC.

  • Natural Resources Commission. 2014. Roster of Indiana Animals, Insects, and Plants That Are Extirpated, Endangered, Threatened or Rare. Information Bulletin #2 (Sixth Amendment. 20pp.

  • Nelson, D. 1993. Colorado Bird Atlas: Manual on Use of Breeding Codes. Denver Museum of Natural History, Denver. 27 pp.

  • Novak, P. 1989. Breeding ecology and status of loggerhead shrike (LANIUS LUDOVICIANUS) in New York. Master's thesis, Cornell Univ., Ithaca, New York.

  • Oakleaf, B, B. Luce, S. Ritter and A. Cerovski, eds. 1992. Wyoming bird and mammal atlas. Wyoming Game and Fish Department, Game Division, Biological Services; Cheyenne, WY. 170 p. + 1994 addendum.

  • Office of Migratory Bird Management. 1987. Migratory nongame birds of management concern in the United States: the 1987 list. US Fish and Wildlife Service, Washington DC. 27 pp + appendices.

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

  • Palmer, W. 1989. Our small eastern shrikes. Auk 15:244-258.

  • 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.

  • Partners in Flight Science Committee. 2013. Population Estimates Database, version 2013. Available at http://rmbo.org/pifpopestimates. Accessed in 2014.

  • Peck, G.K. and R.D. James. 1987. Breeding Birds of Ontario: Nidiology and Distribution. Volume 2: Passerines. Life Sciences Miscellaneous Publication, Royal Ontario Museum, Toronto, Ontario. xi + 387 pp.

  • Pennsylvania Breeding Bird Atlas Project. 1984-1987. UNPUBLISHED

  • Peterjohn, B. G. and W. Zimmerman. 1989. The Birds of Ohio. Indiana University Press, Bloomington, IN.

  • Peterjohn, B. G., and J. R. Sauer. 1995. Population trends of the Loggerhead Shrike from the North American breeding bird survey. Proceedings of the Western Foundation of Vertebrate Zoology 6:117-121.

  • Peterjohn, B.G., and D.L. Rice. 1991. Ohio breeding bird atlas. Ohio Department of Natural Resources, Division of Natural Areas and Preserves, Columbus, Ohio. 416 pp.

  • 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. 1990b. A field guide to western birds. Third edition. Houghton Mifflin Co., Boston. 432 pp.

  • 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.

  • Pittaway, R. 1991. Status of the Loggerhead Shrike on the Carden Plains. 40 pp + 1 Appendix.

  • Proctor, N. 1986. Garden Birds: how to attract birds to your garden. Rodale Press. Emmaus, PA. 160p.

  • RENEW. 2000. Annual Report No. 10. Recovery of Nationally Endangered Wildlife. 16 pp.

  • Rabenold, Patricia P. 1987. Loggerhead Shrikes (Lanius ludovicianus): 1987 Status Report for Indiana. Submitted to the Indiana Department of Natural Resources, Division of Fish and Wildlife, Nongame and Endangered Wildlife Program. 22 pp. plus maps.

  • Rich, T.D., C.J. Beardmore, H. Berlanga, P.J. Blancher, M.S.W. Bradstreet, G.S. Butcher, D.W. Demarest, E.H. Dunn, W.C. Hunter, E.E. Inigo-Elias, J.A. Kennedy, A.M. Martell, A.O. Panjabi, D.N. Pashley, K.V. Rosenberg, C. M. Rustay, J.S. Wendt, T.C. Will. 2004. Partners in Flight North American Landbird Conservation Plan. Cornell Lab or Ornithology. Ithaca, NY.

  • Robbins, C. S., D. Bystrack, and P. H. Geissler. 1986. The breeding bird survey: its first fifteen years, 1965-1979. U.S. Fish and Wildlife Service Resource Publ. 157. Washington, D.C.

  • Robbins, C. S., D. Bystrak, and P. H. Geissler. 1986. The Breeding Bird Survey: its first fifteen years. U.S. Fish and Wildlife Serv. Resource Publ. 157. iii + 196 pp.

  • Robbins, S. D., Jr. 1991. Wisconsin Birdlife: Population and Distribution Past and Present. University of Wisconsin Press, Madison, Wisconsin.

  • Robbins, S. D., Jr. 1991. Wisconsin birdlife: population and distribution past and present. University of Wisconsin Press, Madison.

  • Robert, M. et P. Laporte. 1995. Rapport sur la situation de la Pie-grièche migratrice (Lanius ludovicianus) au Québec. Service canadien de la faune, Série de rapports techniques No. 243. 61 p.

  • Ryke, N., D. Winters, L. McMartin and S. Vest. 1994. Threatened, Endangered and Sensitive Species of the Pike and San Isabel National Forests and Comanche and Cimarron National Grasslands. May 25, 1994.

  • Saskatchewan Natural History Society. 1992. The Loggerhead Shrike, Saskatchewan's Threatened Wildlife. Saskatchewan Natural Resources. Informational Brochure.

  • Sauer, J. R., J. E. Hines, J. E. Fallon, K. L. Pardieck, D. J. Ziolkowski, Jr., and W. A. Link. 2014. The North American Breeding Bird Survey, Results and Analysis 1966 - 2012. Version 02.19.2014 USGS Patuxent Wildlife Research Center, Laurel, MD.
     

  • Sauer, J. R., J. E. Hines, and J. Fallon. 2001. The North American Breeding Bird Survey, Results and Analysis 1966 - 2000. Version 2001.2, USGS Patuxent Wildlife Research Center, Laurel, MD. Available at: http://www.mbr.nbs.gov/bbs/bbs.html.

  • Schneider, K.J., and D.M. Pence, editors. 1992. Migratory nongame birds of management concern in the Northeast. U.S. Department of the Interior, Fish and Wildlife Service, Newton Corner, MA. 400 pp.

  • Schooley, Matthew P. 1991. Winter Distribution and Biology of the Loggerhead Shrike in Indiana. Submitted to Indiana Department of Natural Resources, Division of Fish and Wildlife, Nongame and Endangered Wildlife Program. 15 pp.

  • Scott, S.L., ed. 1987. Field Guide to the Birds of North America, second edition. National Geographic Society, Washington, DC. 464 pp.

  • Scott, T. A., and M. L. Morrison. 1990. Natural history and management of the San Clemente loggerhead shrike. Western Foundation of Vertebrate Zoology, Proceedings 4:23-57.

  • See SERO listing

  • Service canadien de la faune 2003. La faune de l'arrière-pays [en ligne]. Disponible sur le site internet. - Accès : «http://www.cws-scf.ec.gc.ca/hww-fap/index_f.cfm». Service canadien de la faune 2003 [Réf. 28 mai 2003] .

  • Sibley, C.G., and B.L. Monroe, Jr. 1990. Distribution and Taxonomy of Birds of the World. Yale University Press, New Haven, CT. xxiv + 1111 pp.

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

  • Société de la faune et des parcs du Québec. 2003. Les espèces menacées [en ligne]. Disponible sur le site Internet. - Accès :«http://www.fapaq.gouv.qc.ca/fr/etu_rec/esp_mena_vuln/index.htm». La société, 2003 [Réf. 3 novembre 2003] .

  • Stevenson, H.M., and B.H. Anderson. 1994. The Birdlife of Florida. University Press of Florida, 891 pp.

  • Stewart, R. E., and C. S. Robbins. 1958. Birds of Maryland and the District of Columbia. North American Fauna No. 62. U.S. Govt. Printing Office, Washington, D.C.

  • 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.

  • Telfer, E. S. 1992. Habitat change as a factor in the decline of the western Canadian loggerhead shrike, LANIUS LUDOVICIANUS, population. Can. Field-Nat. 106:321-326.

  • Telfer, E. S., et al. 1989. Status and distribution of the loggerhead shrike in western Canada. Can. Wildl. Serv. Prog. Notes 184. 4 pp.

  • Temple, Stanley A., and Bonnie L. Brooks. 1986-1988. The Breeding Distribution, Population Dynamics, and Habitat Availability and Suitability of an Upper Midwest Loggerhead Shrike Population. Funded by the Minnesota Department of Natural Resources. Results in unpublished thesis by Bonnie L. Brooks.

  • 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.

  • Tyler, J. D. 1992. Nesting ecology of the loggerhead shrike in southwestern Oklahoma. Wilson Bull. 104:95-104.

  • U.S. Fish and Wildlife Service (USFWS). 1980. Selected vertebrate endangered species of the seacoast of the U.S. - Moro Bay Kangaroo rat. FWS/OBS-80/01.19.

  • U.S. Fish and Wildlife Service (USFWS). 1987. Migratory nongame birds of management concern in the United States: the 1987 list. U.S. Fish and Wildlife Service, Office of Migratory Bird Management, Washington, D.C. 63 pp.

  • Unknown. 1996. Minutes: Loggerhead shrike Recovery Team meeting, Presqu'ile Provincial Park, September 9, 1996. Unpublished. 6 pp.

  • Virginia Society of Ornithology. 1989. Virginia's breeding birds: an atlas workbook. William Byrd Press, Richmond, Virginia.

  • 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.

  • Wood, MERRILL. 1979. BIRDS OF PENNSYLVANIA. PENNSYLVANIA STATE UNIV., UNIVERSITY PARK. 133 PP.

  • World Wildlife Fund. 1990. The official World Wildlife Fund guide to endangered species of North America. D. W. Lowe, J. R. Matthews, and C. J. Moseley (eds.). Beacham Publishing, Inc. Washington, D.C.

  • Yosef, R. 1992. Behavior of polygynous and monogamous Loggerhead Shrikes and a comparison with Northern Shrikes. Wilson Bulletin 104:747-749.

  • Yosef, R. 1994. Evaluation of the global decline in the true shrikes (family Laniidae). Auk 111:228-233.

  • Yosef, R. 1996. Loggerhead Shrike (Lanius ludovicianus). In A. Poole and F. Gill, editors, The Birds of North America, No. 231. Academy of Natural Sciences, Philadelphia, and American Ornithologists' Union, Washington, DC. 28 pp.

  • Yosef, R. 1996. Loggerhead Shrike (Lanius ludovicianus). In A. Poole and F. Gill, editors, The Birds of North America, No. 231. Academy of Natural Sciences, Philadelphia, and American Ornithologists' Union, Washington, DC. 28 pp.

  • Yosef, R. 1996. Loggerhead Shrike (Lanius ludovicianus). Number 231 in A. Poole and F. Gill, editors. The birds of North America. The Birds of North America, Inc., Philadelphia, Pennsylvania.

  • Yosef, R. 1996. Loggerhead shrike (LANIUS LUDOVICIANUS). IN: Poole, A., and F. Gill, eds. The Birds of North America, No. 231. The Academy of Natural Sciences, Philadelphia, and The American Ornithologists' Union, Washington, D.C.

  • Yosef, R., and F. E. Lohrer. 1995. Loggerhead shrikes, red fire ants, and red herrings. Condor 97:1053-1056.

  • Yosef, R., and T. C. Grubb, Jr. 1992. Territory size influences nutritional condition in nonbreeding loggerhead shrikes (LANIUS LUDOVICIANUS): a ptilochronology approach. Conservation Biology 6:447-449.

  • Yosef, R., and T. C. Grubb, Jr. 1994. Resource dependence and territory size in loggerhead shrikes (LANIUS LUDOVICIANUS). Auk 111:465-469.

  • Yosef, Reuven. 1996. Loggerhead Shrike; The Birds of North America. Vol. 6, No. 231. American Orinithologists' Union. The Academy of Natural Sciences of Philadelphia.

  • Zammit, A.E., and D.A. Sutherland. 2000. COSSARO Candidate V, T, E Species Evaluation Form for Loggerhead Shrike (Lanius ludovicianus migrans). Unpublished report prepared by Natural Heritage Information Centre for Committee on the Status of Species at Risk in Ontario (COSSARO), Ontario Ministry of Natural Resources, Peterborough, Ontario. 7 pp + 4 appendices.

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.