Home/Species/ Southern Watersnake

Nerodia fasciata

(Linnaeus, 1766)

Southern Watersnake

G5Secure Found in 12 roadless areas NatureServe Explorer →

G5SecureGlobal Rank

Least concernIUCN

MediumThreat Impact

Identity

Unique IDELEMENT_GLOBAL.2.102514

Element CodeARADB22030

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVertebrate Animal

IUCNLeast concern

Endemicendemic to a single nation

KingdomAnimalia

PhylumCraniata

ClassReptilia

OrderSquamata

FamilyColubridae

GenusNerodia

Synonyms

Natrix fasciata

Other Common Names

southern watersnake (EN) Southern Water Snake (EN)

Concept Reference

Lawson, R., et al. 1991. Allozyme variation and systematics of the Nerodia fasciata-nerodia clarkii complex of water snakes (Serpentes: Colubridae). Copeia 1991:638-659.

Taxonomic Comments

Salt marsh populations that were formerly included in this species are now regarded as a distinct species, N. clarkii (Lawson 1987, Lawson et al. 1991); hybrids between clarkii and fasciata occur in disturbed areas.

Conservation Status

Review Date2006-09-02

Change Date1996-10-30

Edition Date2006-09-02

Edition AuthorsHammerson, G.

Threat ImpactMedium

Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)

Number of Occurrences81 to >300

Range Extent Comments

The range encompasses the Coastal Plain from North Carolina to southern Florida, and west to Texas, and extends north in the Mississippi Valley to southeastern Missouri and (at least formerly) southern Illinois (Conant and Collins 1991, Palmer and Braswell 1995, Phillips et al. 1999, Johnson 2000, Ernst and Ernst 2003). Introduced and established in southern Texas (Werler and Dixon 2000) and in Sacramento County, California (Balfour and Stitt 2002).

Occurrences Comments

This species is represented by a very large number of occurrences or subpopulations. It is ubiquitous in suitable habitat throughout most of its range (Gibbons and Dorcas 2004). Werler and Dixon (2000) mapped more than 200 collection sites in Texas alone; hundreds of additional collection sites in Louisiana, North Carolina, and Arkansas were mapped by Dundee and Rossman (1989), Palmer and Braswell (1995), and Trauth et al. (2004).

Threat Impact Comments

No major threats are known. Locally, some populations have been reduced or eliminated as a result of drainage of wetlands or removal of aquatic vegetation (Phillips et al. 1999). Many are killed each year by people (Trauth et al. 2004), but this does not constitute a major threat.

Ecology & Habitat

Habitat

Habitat consists primarily of vegetated freshwater ponds, lakes, marshes, wet prairies, sluggish streams and rivers, drainage ditches, and swamps, extending in some areas seaward to the edge of salt water meadows and marshes and mangrove swamps (Barbour 1971; Tennant 1997, 1998; Johnson 2000; Werler and Dixon 2000; Ernst and Ernst 2003; Trauth et al. 2004). This snake basks on banks and in edge vegetation. It shelters in bank-side burrows or under vegetative debris.

Ecology

In South Carolina, emigrated from a drought-stricken site with low water levels (Seigel et al. 1995).

Reproduction

Gives birth to 2-57 young, June to August (average litter size smaller in coastal populations than in inland populations).

Palustrine Habitats

HERBACEOUS WETLANDSCRUB-SHRUB WETLANDFORESTED WETLANDBog/fenRiparian

Other Nations (1)

United StatesN5

Province	Rank	Native
North Carolina	S5	Yes
Tennessee	S3	Yes
Florida	S4	Yes
Texas	S5	Yes
Illinois	SH	Yes
California	SNA	No
Kentucky	SNR	Yes
Oklahoma	S2	Yes
Arkansas	S5	Yes
Arizona	SNA	No
Mississippi	S4	Yes
Louisiana	S5	Yes
Georgia	S5	Yes
Missouri	S4	Yes
Alabama	S4	Yes
South Carolina	S5	Yes

Roadless Areas (12)

Florida (5)

Area	Forest	Acres
Gum Bay	Apalachicola National Forest	11,645
Impassable Bay	Osceola National Forest	2,789
Long Bay	Apalachicola National Forest	5,726
Pinhook	Osceola National Forest	15,405
Savannah	Apalachicola National Forest	1,927

Louisiana (2)

Area	Forest	Acres
Cunningham Brake Research Natural Area	Kisatchie National Forest	1,797
Saline Bayou W & S River Corridor	Kisatchie National Forest	5,355

North Carolina (3)

Area	Forest	Acres
Catfish Lake North	Croatan National Forest	11,299
Pond Pine B	Croatan National Forest	2,961
Sheep Ridge Addition	Croatan National Forest	5,808

Texas (2)

Area	Forest	Acres
Little Lake Creek	National Forests in Texas	596
Winters Bayou	National Forests in Texas	730

References (28)

Ashton, R. E., Jr., and P. S. Ashton. 1981. Handbook of reptiles and amphibians of Florida. Part One: The Snakes. Windward Publishing Company, Miami, Florida. 176 pp.
Balfour, P. S., and E. W. Stitt. 2002. Geographic distribution: Nerodia fasciata fasciata. Herpetological Review 33:150.
Behler, J. L., and F. W. King. 1979. The Audubon Society field guide to North American reptiles and amphibians. Alfred A. Knopf, New York. 719 pp.
Collins, J. T. 1990. Standard common and current scientific names for North American amphibians and reptiles. 3rd ed. Society for the Study of Amphibians and Reptiles. Herpetological Circular No. 19. 41 pp.
Conant, R. 1975. A Field Guide to Reptiles and Amphibians of Eastern and Central North America. Second Edition. Houghton Mifflin Company, Boston, Massachusetts. xvii + 429 pp.
Conant, R., and J. T. Collins. 1998. A field guide to reptiles and amphibians: eastern and central North America. Third edition, expanded. Houghton Mifflin Co., Boston, Massachusetts. 616 pp.
Crother, B. I. (editor). 2008. Scientific and standard English names of amphibians and reptiles of North America north of Mexico, with comments regarding confidence in our understanding. Sixth edition. Society for the Study of Amphibians and Reptiles Herpetological Circular 37:1-84. Online with updates at: http://www.ssarherps.org/pages/comm_names/Index.php
Crother, B. I. (editor). 2012. Scientific and standard English names of amphibians and reptiles of North America north of Mexico, with comments regarding confidence in our understanding. 7th edition. SSAR Herpetological Circular 39:1-92.
Crother, B. I. (editor). 2017. Scientific and standard English names of amphibians and reptiles of North America north of Mexico, with comments regarding confidence in our understanding. 8th edition. SSAR Herpetological Circular 43:1-104. [Updates in SSAR North American Species Names Database at: https://ssarherps.org/cndb]
Dundee, H. A., and D. A. Rossman. 1989. The amphibians and reptiles of Louisiana. Louisiana State University Press, Baton Rouge.
Ernst, C. H., and E. M. Ernst. 2003. Snakes of the United States and Canada. Smithsonian Books, Washington, D.C.
Ernst, C. H., and R. W. Barbour. 1989b. Snakes of eastern North America. George Mason Univ. Press, Fairfax, Virginia. 282 pp.
Fitch, H. S. 1970. Reproductive cycles of lizards and snakes. Univ. Kansas Museum Natural History Miscellaneous Publication 52:1-247.
Gibbons, J. W., and M. E. Dorcas. 2004. North American watersnakes: a natural history. University of Oklahoma Press, Norman. xxvi + 439 pp.
Hebrard, J. J., and R. C. Lee. 1981. A large collection of brackish water snakes from the central Atlantic coast of Florida. Copeia 1981:886-889.
Johnson, T. R. 2000. The amphibians and reptiles of Missouri. Second edition. Missouri Department of Conservation, Jefferson City. 400 pp.
Lawson, R. 1987. Molecular studies of thamnophiine snakes: 1. The phylogeny of the genus Nerodia. J. Herpetology 21:140-157.
Lawson, R., et al. 1991. Allozyme variation and systematics of the Nerodia fasciata-nerodia clarkii complex of water snakes (Serpentes: Colubridae). Copeia 1991:638-659.
Mount, R. H. 1975. The reptiles and amphibians of Alabama. Auburn University Agricultural Experiment Station, Auburn, Alabama. vii + 347 pp.
Palmer, W. M., and A. L. Braswell. 1995. Reptiles of North Carolina. North Carolina State Museum of Natural Sciences, University of North Carolina Press, Chapel Hill, North Carolina.
Phillips, C. A., R. A. Brandon, and E. O. Moll. 1999. Field guide to amphibians and reptiles of Illinois. Illinois Natural History Survey Manual 8. xv + 282 pp.
Seigel, R. A., J. W. Gibbons, and T. K. Lynch. 1995b. Temporal changes in reptile populations: effects of a severe drought on aquatic snakes. Herpetologica 51:424-434.
Tennant, A. 1984. The Snakes of Texas. Texas Monthly Press, Austin, Texas. 561 pp.
Tennant, A. 1997. A field guide to snakes of Florida. Gulf Publishing Company, Houston, Texas. xiii + 257 pp.
Tennant, A. 1998. A field guide to Texas snakes. Second edition. Gulf Publishing Company, Houston, Texas.
Trauth, S. E., H. W. Robison, and M. V. Plummer. 2004. The amphibians and reptiles of Arkansas. University of Arkansas Press.
Webb, R. G. 1970. Reptiles of Oklahoma. University of Oklahoma Press, Norman. 370 pp.
Werler, J. E., and J. R. Dixon. 2000. Texas snakes: identification, distribution, and natural history. University of Texas Press, Austin. xv + 437 pp.