Brown Watersnake
Nerodia taxispilota

** Harmless **

Common Name:

Brown Watersnake

Scientific Name:

Nerodia taxispilota

Etymology:

Genus:

Nerodia is derived from the Greek words neros meaning "flowing" or "liquid" and dia meaning "through"

Species:

taxispilota is derived from the Greek words taxis which means "arrangement" and spilos meaning "spot"

Vernacular Names:

Aspic, false moccasin, great water snake, pied water snake, southern water snake, water rattler

Average Length:

30 - 60 in. (76 - 152 cm)

Virginia Record Length:

68.7 in. (174.5 cm)

Record length:

69.5 in. (176.6 cm)

PHYSICAL DESCRIPTION: The adult has large, square, dark brown blotches on a lighter brown background. One row of squares runs down the back with an alternating row on each side. The belly is yellowish-brown with with dark crescent-shaped or trapezoidal blotches. The patterns darken and become less distinct with age. The juvenile is similar to the adult but lighter. The dorsal scales are strongly keeled with 27-33 scales rows and the anal plate divided. Loreal and preocular scales are present. They are about 8 inches at birth and grow to over 60 inches in some adults. Most adults are from 36-48 inches in length and a 48 inch specimen can weigh as much as 3 1/3 pounds *1006*. This is a large, heavy-bodied snake reaching a maximum total length of 1766 mm (69.5 in.). In Va., max known SVL is 1325 mm (52.2 in.) and max total length was reported by Werler and McCallion to be 1745 mm (68.7 in.). Outside Virginia, the maximum known total length is 69.5 inches *11523*. Black blotches are along the body and tail midline, alternating with similar blotches on each side. Middorsal blotches about 8.5 scale rows wide and 2.5 scales long, these have anterior and posterior projections at the corners, forming a crude H shape; lateral blotches 3-5 scales long and occur on scale rows 1-10; venter yellowish with an irregular pattern of dark brown pigment that occurs in patches; somewhat darker snout; chin brown; infralabials light brown bordered in dark brown; venter of the neck cream with some brown peppering and dark brown spots; little change in color occurs in preservative. This snake has a relatively long head; it is wider than the neck.*10760* Sexual dimorphism: Females are larger than males in SVL (females 707-1325 mm, avg. = 918.7+/-135.4, n=51;; males 462-835 mm, avg. 628.3+/-97.2, n=81) and reach a larger total length (to 1595 mm; males to 1051 mm). The heaviest female known was one collected on 22 January 1929 at Sandbridge, City of Va. Beach, that measured 1259 mm SVL and weighed 2.764 kg.*10760* There are no sexual differences in pattern and color.*10760* Juveniles: Juveniles are identical to adults in pattern and color. At birth, juveniles are 210-218 mm SVL (avg. = 215.3+/-2.1, n=19), 279-296 mm total length (avg. = 288.0+/-5.2), and 9.1-12.1 g body mass (avg. = 11.1+/-0.6).*10760* Confusing Species: Within the range of N. taxispilota, N. sipedon is smaller on average, has complete dark crossbands on the anterior body, half moons on the venter, and considerable black pigmentation, in addition to brown. Nerodia erythrogaster is uniform dark brown dorsally with a reddish or orangish venter.*10760*

REPRODUCTION: The females bear between 12 and 50 living young in the late summer *1006*. Mating apparently occurs in the spring. Yolking of follicles was rapid in spring and ovulation occurred in late June. Number of yolking follicles or embryos per litter was 19-63 (avg. = 33.9+/-12.2, n=23), however the number of full-term embryos was 19-41 (avg. = 28.0+/-10.6, n=5). There was a positive correlation between litter size and female size; larger females bear larger litters. Birth occurs in late August to mid September. *10760* This is an abundant snake where it occurs, however, no studies of the population ecology of this species have been published.*10760*

BEHAVIOR: During the day, this species spends much time basking in the sun. They may climb to a height of 15 or 20 feet above the water and lay for hours without stirring. They consume mainly fish but also take frogs and other aquatic animals *1006*. N. taxispilota usually bites when caught, and a large one can inflict a nasty wound from its long teeth. They also squirt musk from glands at the base of the tail and sometimes defecate.*10760* Thorp has observed this species to be quite docile. This species will allow one to approach it and almost touch it before it moves. Thorp has generally observed this species basking on branches or vegetation overhanging the water. Often, there are multiple snakes using the same branch or tree *11523*.

AQUATIC/TERRESTRIAL ASSOCIATIONS: Juveniles and small adults are preyed upon by racoons, mink, herons, kingsnakes and other shoreline preditors *1006*. Large numbers are killed by humans. In the Appomattox River population studied by White et al., partial tails occurred in 21.4 % of the male sample and 22.2% of the female sample, and the frequency of tail breakage increased with body size. They speculated that snapping turtles (Chelydra serpentina) biting the snake's tail as they dangled in the water while basking, coupled with this snake's behavior of twisting vigorously when caught, was the cause of high frequencies. *10760*

POPULATION PARAMETERS: The longevity record for this species is 6 years and 2 months *11523*.

References for Life History

  • 8670 - Gibbons, J. Whitfield & Dorcas, Michael E. 2004. North American Watersnakes - A Natural History. University of Oklahoma Press. 438 pages.
  • 1006 - Linzey, D.W., M.J. Clifford, 1981, Snakes of Virginia, Univ. of Virginia Press, Charlottesville, VA
  • 10760 - Mitchell, J. C., 1994, The Reptiles of Virginia, 352 pgs., Smithsonian Institution Press, Washington, DC
  • 11523 - Thorp, T.J., 2001, Personal Communication, Expert Review for GAP Analysis Project, Three Lakes Nature Center and Aquarium

Photos:

*Click on a thumbnail for a larger version.


Verified County/City Occurrence

Charles City County
Chesapeake City
Chesterfield County
Colonial Heights City
Henrico County
Hopewell City
James City County
King William County
New Kent County
Norfolk City
Prince George County
Suffolk City
Surry County
Virginia Beach City
Verified in 14 Counties/Cities.



FROGS

Virginia is home to 28 species of frogs and toads.

SALAMANDERS

We have a large diversity of salamanders consisting of 56 different species and subspecies.

LIZARDS

Virginia is home to 9 native lizard species and two introduced species, the Mediterranean Gecko and the Italian Wall Lizard.

SNAKES

The Commonwealth is home to 34 species and subspecies of snake. Only 3 species are venomous.

TURTLES

Virginia has 25 species and subspecies of turtle. Five of these species are sea turtle.