Coluber constrictor 

Scope: Global
Language: English

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Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Reptilia Squamata Colubridae

Scientific Name: Coluber constrictor Linnaeus, 1758
Common Name(s):
English Eastern Racer, Racer
Coluber mormon Baird & Girard, 1852
Taxonomic Notes: Western populations have been proposed to constitute a distinct species, Coluber mormon (Fitch et al. 1981), but this distinction has been demonstrated to be invalid (Corn and Bury 1986; see also Greene 1984).

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2013
Date Assessed: 2012-05-07
Assessor(s): Hammerson, G.A., Acevedo, M., Ariano-Sánchez, D. & Johnson, J.
Reviewer(s): Bowles, P.
Listed as Least Concern in view of its wide distribution, tolerance of a broad range of habitats, presumed large population, and because it is unlikely to be declining fast enough to qualify for listing in a more threatened category.
Previously published Red List assessments:

Geographic Range [top]

Range Description:This species occurs through most of the United States, and ranges into southern Canada and northern and eastern Mexico, discontinuously southward to Guatemala and Belize. It extends from southern British Columbia, southern Saskatchewan, Wisconsin, Michigan, southern Ontario, New York, and southern Maine southward in the United States to southern California, Arizona, New Mexico, Texas, the Gulf Coast, and southern Florida, and southward through northeastern, central, and southern Mexico to Guatemala and Belize (Wilson 1978, Campbell 1998, Lee 2000, Stafford and Meyer 2000, Ernst and Ernst 2003, Stebbins 2003). Elevational range extends from sea level to about 2,550 meters (8,300 feet). A record for Durango, Mexico, evidently is erroneous (Webb 2001).
Countries occurrence:
Belize; Canada; Guatemala; Mexico; United States
Additional data:
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:This species is represented by a very large number of occurrences or subpopulations (at least several hundred). The total adult population size is unknown but probably exceeds 1,000,000. This snake is common in most of its very large range in the United States but appears to be rare at the southern extent of the range in southern Mexico, Guatemala, and Belize (Campbell 1998, Lee 2000). The extent of occurrence, area of occupancy, number of subpopulations, and population size are very large and probably relatively stable. The southern subpopulations in Mexico, Guatemala, and Belize are represented by a few specimens.
Current Population Trend:Stable
Additional data:

Habitat and Ecology [top]

Habitat and Ecology:Habitats encompass a wide range of lowland and montane areas, including deserts, prairies, sandhills, shrublands, woodlands, forests, canyons, streamsides, and semi-agricultural areas. These snakes are absent from the driest deserts and highest mountains (subalpine zones and higher). They commonly climb shrubs and small trees. When inactive, they hide underground, in crevices, or under surface cover. Adults often hibernate communally, sometimes partly submerged in water. Eggs are laid in underground tunnels or burrows, rotting stumps, sawdust piles, or under rocks. Oviposition sites may be up to at least several hundred meters from the usual home range (Brown and Parker 1976, Iverson et al. 1995).
Movement patterns:Not a Migrant

Use and Trade [top]

Use and Trade: This species is not utilized or traded to any significant degree.

Threats [top]

Major Threat(s): No major threats have been identified. Historically, some populations undoubtedly experienced significant declines, particularly in major agricultural regions of intensive cultivation. Remaining populations are extensive and not threatened in most areas.

Conservation Actions [top]

Conservation Actions: Currently, this species is of relatively low conservation concern and does not require significant additional protection or major management, monitoring, or research action, other than clarification of the taxonomic status of various subpopulations. Many occurrences are in national parks and other protected areas.

Classifications [top]

1. Forest -> 1.4. Forest - Temperate
2. Savanna -> 2.1. Savanna - Dry
3. Shrubland -> 3.4. Shrubland - Temperate
3. Shrubland -> 3.5. Shrubland - Subtropical/Tropical Dry
3. Shrubland -> 3.8. Shrubland - Mediterranean-type Shrubby Vegetation
4. Grassland -> 4.4. Grassland - Temperate
4. Grassland -> 4.5. Grassland - Subtropical/Tropical Dry
5. Wetlands (inland) -> 5.8. Wetlands (inland) - Seasonal/Intermittent Freshwater Marshes/Pools (under 8ha)
5. Wetlands (inland) -> 5.9. Wetlands (inland) - Freshwater Springs and Oases
0. Root -> 6. Rocky areas (eg. inland cliffs, mountain peaks)
8. Desert -> 8.1. Desert - Hot
8. Desert -> 8.2. Desert - Temperate
14. Artificial/Terrestrial -> 14.2. Artificial/Terrestrial - Pastureland

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
  Occur in at least one PA:Yes
In-Place Species Management
In-Place Education
1. Research -> 1.1. Taxonomy

Bibliography [top]

Brown, W.S. and W. S. Parker 1976. Movement ecology of Coluber constrictor near communal hibernacula. Copeia 1976: 225-242.

Campbell, J.A. 1998. Amphibians and Reptiles of Northern Guatemala, the Yucatán and Belize. University of Oklahoma Press, Norman, Oklahoma.

Campbell, J.A. 2001. Guide to the Reptiles and Amphibians of Guatemala. University of Texas, Arlington, Texas. (Web published: ).

Conant, R. and Collins, J.T. 1991. A Field Guide to Reptiles and Amphibians: Eastern and Central North America. Third Edition. Houghton Mifflin Company, Boston, Massachusetts.

Ernst, C.H. and Ernst, E.M. 2003. Snakes of the United States and Canada. Smithsonian Books, Washington, D.C.

IUCN. 2013. IUCN Red List of Threatened Species (ver. 2013.2). Available at: (Accessed: 13 November 2013).

Iverson, J.B., Higgins, H., Sirulnik, A.G. and Young, C.A. 1995. Coluber constrictor flaviventris (Eastern Yellow-bellied Racer): Nesting. Herpetological Review 26(3): 147-148.

Köhler, G. 2003. Reptiles of Central America. Herpeton, Germany.

Lee, J.C. 2000. A Field Guide to the Amphibians and Reptiles of the Maya World. Cornell University Press, Ithaca, New York.

Savage, J.M. 2002. The Amphibians and Reptiles of Costa Rica: A Herpetofauna between two Continents, between two Seas. University of Chicago Press, Chicago.

Stebbins, R.C. 2003. A Field Guide to Western Reptiles and Amphibians. Third Edition. Houghton Mifflin Company, Boston, Massachusetts.

Webb, R.G. 2001. Proposed deletion of two colubrid snakes from the Mexican state of Durango herpetofauna. Herpetological Review 32: 159-160.

Wilson, L.D. 1978. Coluber constrictor. Catalogue of American Amphibians and Reptiles. 218: 1-4.

Wilson, L.D., Townsend, J.H. and Johnson, J.D. (eds). 2010. Conservation of Mesoamerican Amphibians and Reptiles. pp. 816. Eagle Mountain Publishing, Eagle Mountain, Utah.

Citation: Hammerson, G.A., Acevedo, M., Ariano-Sánchez, D. & Johnson, J. 2013. Coluber constrictor. The IUCN Red List of Threatened Species 2013: e.T63748A3128579. . Downloaded on 21 September 2018.
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