Catharus bicknelli - (Ridgway, 1882)
Bicknell's Thrush
Taxonomic Status: Accepted
Related ITIS Name(s): Catharus bicknelli (Ridgway, 1882) (TSN 554148)
French Common Names: grive de Bicknell
Spanish Common Names: Tordo
Unique Identifier: ELEMENT_GLOBAL.2.106330
Element Code: ABPBJ18120
Informal Taxonomy: Animals, Vertebrates - Birds - Perching Birds
 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Aves Passeriformes Turdidae Catharus
Genus Size: C - Small genus (6-20 species)
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Concept Reference
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Concept Reference: American Ornithologists' Union (AOU). 1998. Check-list of North American birds. Seventh edition. American Ornithologists' Union, Washington, D.C. [as modified by subsequent supplements and corrections published in The Auk]. Also available online: http://www.aou.org/.
Concept Reference Code: B98AOU01NAUS
Name Used in Concept Reference: Catharus bicknelli
Taxonomic Comments: Formerly included as a subspecies of C. minimus; elevated to full species status by Ouellet (1993) (see also McLaren 1995); not known to intergrade/hybridize with C. minimus. AOU (1995) accepted full species status for C. bicknelli Formerly placed in genus Hylocichla (AOU 1983).
Conservation Status
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NatureServe Status

Global Status: G4
Global Status Last Reviewed: 07Apr2016
Global Status Last Changed: 03Dec1996
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G4 - Apparently Secure
Reasons: Breeds in the northeastern U.S. and southeastern Canada, winter records are from the West Indies; apparently stable in New York/New England, but overall conservation status is not well known.
Nation: United States
National Status: N4B (19Mar1997)
Nation: Canada
National Status: N2B,N2M (02Dec2017)

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 Connecticut (SNA), Delaware (SNA), Georgia (SNA), Maine (S3B), Maryland (SNA), Massachusetts (SXB), New Hampshire (S2S3B), New Jersey (SNA), New York (S2S3B), North Carolina (SNA), Pennsylvania (SNA), Rhode Island (SNA), South Carolina (SNA), Vermont (S2B), Virginia (SNA)
Canada New Brunswick (S2B,S2M), Nova Scotia (S1S2B), Ontario (SNA), Prince Edward Island (SHB), Quebec (S3)

Other Statuses

Canadian Species at Risk Act (SARA) Schedule 1/Annexe 1 Status: T (20Jun2012)
Committee on the Status of Endangered Wildlife in Canada (COSEWIC): Threatened (27Nov2009)
Comments on COSEWIC: Reason for designation: This species has one of the most restricted breeding ranges among the forest birds of North America. It inhabits the forests of montane and cool coastal zones, as well as high elevation regenerating forests over 600m in Quebec, New Brunswick, Nova Scotia and the northeastern United States. It winters in the Greater Antilles, where the bulk of its population appears to be in the Dominican Republic. Despite the difficulty to adequately monitor the species, all the available indices on trends point to significant declines in population and area of occupancy. Preliminary results from the Maritimes Breeding Bird Atlas project suggest a 40% decline in the area occupied over the last three generations, while the High Elevation Landbirds Program suggests more dramatic declines in the same regions. Recent surveys in Quebec also indicate declines in some locations. While reasons for the decline are unclear, habitat loss on the wintering grounds, management practices such as pre-commercial thinning in regenerating forests and climate change are leading to a reduction of suitable high-elevation habitat.

Status history: Designated Special Concern in April 1999. Status re-examined and designated Threatened in November 2009.

IUCN Red List Category: VU - Vulnerable

NatureServe Global Conservation Status Factors

Range Extent: 250-20,000 square km (about 100-8000 square miles)
Range Extent Comments: BREEDING: eastern New York (south to the Catskill Mountains), Massachusetts (formerly, on Mount Greylock), central and northern Vermont, northern New Hampshire, Maine, southern Nova Scotia (has disappeared from Seal Island), Magdalen Islands (at least formerly), Gaspe Peninsula, interior highlands of New Brunswick, and (formerly) along the north shore of the Gulf of St. Lawrence from Natashquan, Quebec, east to Cape Saint Charles, southern Labrador (AOU 1957, Rimmer et al. 1993). In the U.S., mainly at elevations above 3000 ft; in 1992, found on 4 peaks lower than 3000 ft. In Quebec, elevations of 175-1160 (Ouellet 1993). NON-BREEDING: poorly documented; known from Hispaniola, Cuba, Puerto Rico, and St. Croix; winter stronghold almost certainly is the Dominican Republic (Rimmer 1996); not known from Central or South America (Ouellet 1993). Migration records encompass eastern coastal states of U.S. and Bahamas (Ouellet 1993).

Area of Occupancy: 26 to >12,500 4-km2 grid cells
Area of Occupancy Comments: An estimate. Males have a home range size of about 5 hectares (Rimmer, et. al. 2001).

Number of Occurrences: 81 to >300
Number of Occurrences Comments: In 1992-1993 surveys, found on 230 peaks of 332 surveyed in New York and New England found at 61 of 71 historical breeding sites surveyed (Rimmer 1996).

Population Size: 10,000 - 100,000 individuals
Population Size Comments: Total breeding population probably is 7500-15,000 pairs (Rimmer 1996). In June-July surveys in 1992, populations ranged from only one or two pairs on 70 peaks to as many as 250 pairs on Mount Mansfield in Vermont (Rimmer et al. 1993; Audubon, November-December 1993, pp. 116-118). The most recent surveys has a global estimate of 95,000 to 126,000 individuals (Birdlife International, 2014).

Number of Occurrences with Good Viability/Integrity: Many to very many (41 to >125)
Viability/Integrity Comments: An estimate. Some undoubtedly in state parks / wildlife management areas, etc. Much of habitat is probably fairliy undisturbed by human activity.

Overall Threat Impact Comments: Threatened by the damaging effects of acid precipitation and airborne pollution, habitat loss from ski area development and transmission tower construction, and overuse by hikers; global climate change is a potential threat (Rimmer et al. 1993). Wind power development is an increasing threat in parts of the breeding range (Rimmer 1996). Deforestation in the winter range probably has eliminated much of its habitat and human settlements are expected to double over the next few years (Rimmer 1996; National Audubon Society, 2014).

Short-term Trend: Decline of 30-50%
Short-term Trend Comments: May be declining in north and south, but distribution in New England and New York has not undergone significant recent change; conservation status is uncertain (Rimmer et al. 1993). Annual declines of 7 - 19% have been documented in parts of the species' breeding range (Birdlife International, 2014);

Long-term Trend: Unknown
Long-term Trend Comments: Locall extirpations documented but no clear evidence of rangewide declines (Rimmer, et. al. 2001).

Intrinsic Vulnerability: Moderately vulnerable
Intrinsic Vulnerability Comments: Degradation of its limited wintering range in the Greater Antilles is a problem (National Audubon Society, 2014; Rimmer, et. al., 2001), as is elimination of its breeing range due to climate change and logging.

Environmental Specificity: Moderate. Generalist or community with some key requirements scarce.
Environmental Specificity Comments: Utilizes montane forests, which is getting to be a scarce resource in its wintering range although such forests are more common in its breeding range (Rimmer, et.al. 2001).

Other NatureServe Conservation Status Information

Inventory Needs: Determine current population size; determine range in Canada (Rimmer 1996).

Protection Needs: Better vegetation management at all sites where this species either breeds or winters is needed

Distribution
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Global Range: (250-20,000 square km (about 100-8000 square miles)) BREEDING: eastern New York (south to the Catskill Mountains), Massachusetts (formerly, on Mount Greylock), central and northern Vermont, northern New Hampshire, Maine, southern Nova Scotia (has disappeared from Seal Island), Magdalen Islands (at least formerly), Gaspe Peninsula, interior highlands of New Brunswick, and (formerly) along the north shore of the Gulf of St. Lawrence from Natashquan, Quebec, east to Cape Saint Charles, southern Labrador (AOU 1957, Rimmer et al. 1993). In the U.S., mainly at elevations above 3000 ft; in 1992, found on 4 peaks lower than 3000 ft. In Quebec, elevations of 175-1160 (Ouellet 1993). NON-BREEDING: poorly documented; known from Hispaniola, Cuba, Puerto Rico, and St. Croix; winter stronghold almost certainly is the Dominican Republic (Rimmer 1996); not known from Central or South America (Ouellet 1993). Migration records encompass eastern coastal states of U.S. and Bahamas (Ouellet 1993).

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 CT, DE, GA, MAextirpated, MD, ME, NC, NH, NJ, NY, PA, RI, SC, VA, VT
Canada NB, NS, ON, PE, QC

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


U.S. Distribution by County Help
State County Name (FIPS Code)
NH Carroll (33003), Coos (33007), Grafton (33009)
NY Clinton (36019), Essex (36031), Franklin (36033), Greene (36039), Hamilton (36041), Ulster (36111), Warren (36113)
VT Addison (50001), Bennington (50003), Chittenden (50007), Essex (50009), Lamoille (50015), Orleans (50019), Rutland (50021), Washington (50023), Windham (50025)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
01 Lower Androscoggin (01040002)+, Saco (01060002)+, Pemigewasset (01070001)+, Upper Connecticut (01080101)+, Waits (01080103)+, Black-Ottauquechee (01080106)+, West (01080107)+, Deerfield (01080203)+
02 Upper Hudson (02020001)+, Sacandaga (02020002)+, Hudson-Hoosic (02020003)+, Mohawk (02020004)+, Schoharie (02020005)+, Middle Hudson (02020006)+, Rondout (02020007)+, East Branch Delaware (02040102)+, Middle Delaware-Mongaup-Brodhead (02040104)+
04 Black (04150101)+, Raquette (04150305)+, St. Regis (04150306)+, English-Salmon (04150307)+, Otter Creek (04150402)+, Winooski River (04150403)+, Ausable River (04150404)+, Lamoille River (04150405)+, Saranac River (04150406)+, Missiquoi River (04150407)+, Lake Champlain (04150408)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Basic Description: A songbird (thrush).
Diagnostic Characteristics: Smaller and typically richer brown dorsally than the gray-cheeked thrush; tail color (with various amounts of chestnut) contrasts with the back color in Bicknell's whereas there is little contrast in gray-cheeked thrush; pale area at base of bill is yellowish in Bicknell's, fleshy-pink in gray-cheeked; white of ventral region is duller than in gray-cheeked thrush; songs differ as well, with those of Bicknell's ending on an even or ascending pitch whereas the gray-cheeked's descends (Rimmer et al. 1993, Ouellet 1993). However, Bicknell's thrush from the Gaspe Peninsula lacks bright yellow on the mandible, and some Newfoundland gray-cheeked thrushes have more extensively pale mandibles, "warm" plumage tones, and appear to have a chestnut tail (McLaren 1995). In migration, Bicknell's thrush and gray-cheeked thrush probably cannot be reliably separated without specimens in hand.
Reproduction Comments: Eggs are laid in June (mostly) and July. Clutch size is 3-6 (average 3-4). Incubation, by female, lasts 12-14 days. Young are tended by both parents, leave nest at 11-13 days. Pairs with failed nests early in the season may renest. Causes of nest failure include predation by red squirrel and blue jay and desertion (Rimmer 1996).
Ecology Comments: At Mount Mansfield, Vermont, density was estimated at about 50-60 pairs/40 ha in optimal habitat (Rimmer 1996).
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: Y
Mobility and Migration Comments: Migrates through the U.S. mainly east of the Alleghenies (AOU 1957); through eastern coastal states (Ouellet 1993). Departs from northern New England in late Septemeber or early October, returns in mid- to late May (Rimmer 1996).
Palustrine Habitat(s): Riparian
Terrestrial Habitat(s): Forest - Conifer, Forest - Hardwood, Forest - Mixed, Shrubland/chaparral, Woodland - Conifer, Woodland - Hardwood, Woodland - Mixed
Habitat Comments: In New England and New York, inhabits montane forests, primarily areas dominated by stunted balsam fir and red spruce at elevations above 3000 ft (Rimmer et al. 1993). Habitats in Canada include mountaintop and dense coastal coniferous forests as well as mixed second-growth regenerating stands (Rimmer 1996). In southern Quebec, occurs mainly in second growth stands characterized by relatively young conifers of small size (balsam fir, white spruce) intermixed with a variety of deciduous species typical of second-growth regeneration (PRUNUS sp., BETULA sp., AMELANCHIER sp., ACER SPICATUM, POPULUS sp.) following forest fires or clear cutting; trees seldom exceed 10 m in height (Ouellet 1993). Nests generally are situated close to the trunk in the upper half of a small-to-medium-sized fir or spruce, typically in conifer thickets, often on steep slopes (Rimmer 1996). In migration and winter also in deciduous forest, forest borders, open woodland, second growth, and scrub. Winter habitat may be restricted to primary tropical forest (Rimmer et al. 1993). Occurred at fairly high densities in moist, broad-leafed montane forest in the Dominican Republic (Rimmer 1996).
Adult Food Habits: Frugivore, Invertivore
Immature Food Habits: Frugivore, Invertivore
Food Comments: Eats mainly insects and other invertebrates and small fruits (Terres 1980).
Adult Phenology: Crepuscular, Diurnal
Immature Phenology: Crepuscular, Diurnal
Phenology Comments: Singing activity is most frequent in early to mid-June (Rimmer et al. 1993).
Economic Attributes Not yet assessed
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Management Summary
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Monitoring Requirements: Presence-absence surveys are best conducted during the first three weeks of June (Rimmer et al. 1993).
Biological Research Needs: Determine population trends, demographics, impacts of habitat degradation, migration routes and ecology, and winter ecology (Rimmer 1996).
Population/Occurrence Delineation
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Group Name: Passerines

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

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

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

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

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

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

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

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

Date: 10Sep2004
Author: Hammerson, G.

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

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

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

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

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

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

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

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

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

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

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

Date: 03Sep2004
Author: Hammerson, G.

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

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

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

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

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

Date: 10Sep2004
Author: Hammerson, G.
Notes: These specs pertain to nonmigratory species.
Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
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Authors/Contributors
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NatureServe Conservation Status Factors Edition Date: 07Oct2014
NatureServe Conservation Status Factors Author: Jue, Dean K.
Element Ecology & Life History Edition Date: 15May1995
Element Ecology & Life History Author(s): Hammerson, G.

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

References
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  • American Ornithologists Union. 1995. Fortieth supplement to the American Ornithologists' Union checklist of North American birds. Auk 112: 819-830.

  • American Ornithologists' Union (AOU). 1957. The A.O.U. Check-list of North American Birds, 5th ed. Port City Press, Inc., Baltimore, MD. 691 pp.

  • American Ornithologists' Union (AOU). 1995. Fortieth supplement to the American Ornithologists' Union Check-list of North American Birds. Auk 112:819-30.

  • American Ornithologists' Union (AOU). 1998. Check-list of North American birds. Seventh edition. American Ornithologists' Union, Washington, D.C. [as modified by subsequent supplements and corrections published in The Auk]. Also available online: http://www.aou.org/.

  • American Ornithologists' Union. 1957. Check-list of North American birds. Fifth edition. American Ornithologists' Union. Port City Press, Inc. Baltimore, MD. 691 pp. (Reprinted in 1961 by Port City Press, Inc., Baltimore, Maryland.)

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

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

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

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  • Ellison, W.G. 2001. Population structure and gene flow in two long distance migrant birds, the Bicknell's Thrush (Catharus bicknelli) and Veery (C. fuscescens). Ph.D. Dissertation, SUNY Albany.

  • Environment Canada. 1999. Last update: April 27, 2001. Bicknells Thrush. In Species at Risk in Canada. Online. Available: http://www.speciesatrisk.gc.ca/species/English/SearchDetail.cfm?SpeciesID=584

  • Evans, W. R. 1994. Nocturnal flight call of Bicknell's thrush. Wilson Bull. 106:55-61.

  • 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

  • Gauthier, J., and Y. Aubry (editors). 1996. The breeding birds of Quebec. Atlas of the breeding birds of southern Quebec. Association quebecoise des groupes d'ornithologues, Province of Quebec Society for the Protection of Birds, Canadian Wildlife Service, Environment Canada, Quebec Region, Montreal, 1302 pp.

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

  • Goetz, J.E., K.P. McFarland, and C.C. Rimmer. 2003. Multiple paternity and multiple male feeders in Bicknell's Thrush (Catharus bicknelli). The Auk 120:1044-1053.

  • Hale, S.R. 2006. Using satellite imagery to model distribution and abundance of Bicknell's Thrush (Catharus bicknelli) in New Hampshire's White Mountains. The Auk 123:1038-1051.

  • Hart, J.A., and J.D. Lambert. 2007. Mountain Birdwatch 2006. Final report to the U.S. Fish and Wildlife Service. Vermont Institute of Natural Science Technical report 07-3, Quechee, Vermont.

  • Hobson, K.A., K.P. McFarland, L.I. Wassenaar, C.C. Rimmer, and J.E. Goetz. 2001. Linking breeding and wintering grounds of Bicknell's Thrushes using stable isotope analyses of feathers. The Auk 118:16-23.

  • Hobson, K.A., Y. Aubry, and L.I. Wassenaar. 2004. Migratory connectivity in Bicknell's Thrush: locating missing populations with hydrogen isotopes. The Condor 106:905-909.

  • Holmes, R.T., and R.H. Sawyer. 1975. Oxygen consumption in relation to ambient temperature in five species of forest-dwelling thrushes (Hylocichla and Catharus). Comparative Biochemisty and Physiology 50A:527-531.

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

  • Jenkins, J, and A. Keal. 2004. The Adirondack Atlas: a geographic portrait of the Adirondack Park. Syracuse University Press, NY. 275pp.

  • King, D.I., J.D. Lambert, J.P. Buonaccorsi, and L.S. Prout. in press. Avian population trends in the vulnerable montane forests of the northern Appalachians, USA. Biodiversity and Conservation.

  • Lambert, J.D., K.P. McFarland, C.C Rimmer, S.D. Faccio, and J.L. Atwood. 2005. A practical model of Bicknell's Thush distribution in the northeastern United States. Wilson Bulletin 117:1-11.

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

  • McLaren, I. A. 1995. Field identification and taxonomy of Bicknell's thrush. Birding 27(5):358-366.

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