Some people ask this question when they see a snake inthe water. Unfortunately, many people assume all snakesin the water are Water Moccasins and kill them “just incase.” Along with sharks and bats, snakes are amongthe most misunderstood and mistreated animals on earth.Yes, some species of snakes, including the WaterMoccasin (Agkistrodon piscivorous), also known as theCottonmouth, are venomous and therefore a potentialdanger. However, of the 41 snake species native toGeorgia and South Carolina, only six are venomous—all others are completely harmless. Among the 35harmless non-venomous snakes, five species of WaterSnakes (Nerodia spp.) are often unfortunate victims ofmistaken identity—thought to be Water Moccasins. Thisbrochure was developed to highlight the differencesbetween Water Snakes and Water Moccasins with thehope that familiarity with these snakes will prevent further

Range (in green) of the Water Moccasin (Cottonmouth) in Georgiaand South Carolina. State capitals are indicated by red stars; majorreservoirs outside of the Water Moccasin’s range are as follows: A–Lake Allatoona; L–Lake Lanier; H–Lake Hartwell; R–Lake Russell;G–Lake Greenwood; M–Lake Murray; W–Wateree Lake.

AL

H

RG M

W

Non-venomous Water Snakes, such as this Brown Water Snake, maybe mistaken for venomous Water Moccasins.

unnecessary killing of non-venomous snakes (which isillegal in Georgia) commonly found in aquatic habitatsin Georgia and South Carolina.

However, this information is not provided to point outwhich species to kill and which species not to kill. TheWater Moccasin’s rumored reputation as a vicious snakefar exceeds its true character. This is not an aggressivesnake that attacks without provocation, and rarely doesit strike even when harassed. Venom is a preciouscommodity that Water Moccasins use for subduing prey,and wasting venom on anything that is not “food” mayprevent a snake from catching itsnext meal. Further, the gapeddisplay of the “cottony”inner-mouth of a WaterMoccasin is not an act ofaggression, but rather awarning of its toxicity—nodifferent than the rattling behaviorof Rattlesnakes or the bright warning colors of the CoralSnake. Venomous snakes pose very little threat to humanswho leave them alone—the vast majority of snakebitesresult from attempting to capture, harass, or kill them.

There are five species of large Water Snakes native toGeorgia and South Carolina—Eastern Green Water Snake(Nerodia floridana), Brown Water Snake (Nerodiataxispilota), Red-Bellied Water Snake (Nerodiaerythrogaster), Banded Water Snake (Nerodia fasciata),and Northern Water Snake (Nerodia sipedon). Adult

Eastern Green Water Snake.

Adult Red-Bellied Water Snake.

WATER MOCCASINS (COTTONMOUTHS)VS. WATER SNAKES

Water Snakes and Water Moccasins may be very similarin appearance—both are both large, heavy-bodiedspecies with rough scales and relatively dull coloration.However, the following characteristics of behavior andappearance should assist anyone interested indifferentiating between the two:

Range and habitat...The first step in discerning “Is it a Water Moccasin?”should be to refer to the distribution map that illustratesthe range of the Water Moccasin. Collectively, WaterSnakes can be found in every county of Georgia and SouthCarolina, unlike the Water Moccasin, which does notnaturally occur in most of the northern half of either

Water Moccasin/Cottonmouth (Venomous)

Juvenile Red-Bellied

Banded

Red-Bellied

Northern

Eastern Green Brown

Water Snakes (Non-Venomous)Occur in aquatic habitats throughout GA and SC; bask inlimbs overhanging water; typically swim below the watersurface; if banded, have bands that are widest on top andnarrow on the sides; have round eye pupils; and have adouble row of scales on the underside of their tails.

Do not occur naturally in most of northern GA and SC; baskon land or on logs and stumps near the water surface;swim with their heads elevated above the water and theirbodies riding on the water surface; may vibrate their tailsand gape their mouths when threatened; if banded, havebands that are widest on the sides and narrow on top; havetriangular heads with elliptical eye pupils and a heat-sensingpit; and have a single row of scales on the underside oftheir tails.

JuvenileAdult–dark phase

Adult–light phaseAdult–banded

Water Moccasins(left) rarely climb,whereas WaterSnakes, like thisBanded Water Snake(bottom), typicallybask on limbs thathang over water.

Mouth-gape warning behavior (top right) and head angle typicalof Water Moccasins.

state. However, since distributions are not static andsnakes may be moved around intentionally oraccidentally, physical features and behaviors ofquestionable snakes should also be examined. Althoughit is difficult to summarize the habitat preferences of thesetwo snakes, in general Water Moccasins do not preferlarge, open reservoirs, whereas some Water Snakes do.Water Moccasins tend to inhabit slow-moving streams,swamps, and backwaters.

Basking behavior...Stories of Water Moccasins falling from high overhanginglimbs into boats are most likely based onmisidentifications. Water Moccasins typically bask onland, stumps, or logs near the water surface, and onlyoccasionally climb to low limbs when access is affordedby vines or a gradually sloping branch. Water Snakes arevery agile climbers and spend a great deal of time baskingon the limbs of shrubs and trees overhanging the water.

Water Snakes, like this Northern Water Snake, have bands that arewidest on top, whereas Water Moccasins have bands that are wideston the sides.

A Northern Water Snake in a threat posture, with the head flared.

A juvenile Water Moccasin swimming. Also illustrated is the typical“hourglass” banding pattern.

Swimming behavior...When disturbed, Water Moccasins either hold theirground or swim away; when swimming, their heads areusually elevated above the water and their bodies appearoverly buoyant, riding on, or nearly on, the water surface.Water Snakes, on the other hand, do not swim high onthe water, their heads are not elevated, and they moretypically swim below the surface. When Water Snakes

are disturbed, they almost always flee by diving beneaththe water.

Head positioning and mouth-gaping behavior...Water Moccasins typically keep their heads cocked at anapproximately 45° angle, and when threatened will gapetheir mouth revealing the whitish inner lining. AlthoughWater Snakes do not display either of these behaviorsthey, too, have whitish coloration in the mouth lining.Therefore, dead Water Moccasins cannot be positivelyidentified based solely on the color of their inner-mouthlining (Caution: Venommay remain fully toxiceven in dead snakes. Itis best to leave deadsnakes of uncertainidentification alone).

Pattern...The two most common Water Snakes in Georgia andSouth Carolina, Banded and Northern, have bands thatare widest on top. Juvenile and patterned adult WaterMoccasins have “hollow” bands that are widest on thesides and appear to be “hourglass shaped.”

Underside of tail...Water Moccasins have a single row of scales (similar tothe belly scales) on the underside of their tail, while adouble row of scales is present on Water Snakes(Caution: If uncertain as to species, scale characteristicsshould only be examined on dead snakes and shed skins).

when they feel threatened, making it look triangular.However, the elliptical shape of the pupil (round in WaterSnakes) and the presence of a pit between the eye andnostril (absent in Water Snakes) are reliablecharacteristics of Water Moccasins.

This document was a joint production of the GeorgiaDepartment of Natural Resources Nongame-EndangeredWildlife Program and the Savannah River Ecology Laboratory.Text by John Jensen (GADNR); Photos by David E. Scott (SREL)and John Jensen (GADNR); Layout and design by Laura L.Janecek (SREL).

Tail vibration...In addition to mouth-gaping, Water Moccasins will oftenrapidly vibrate their tail when agitated or threatened.Although several other non-venomous snakes also exhibitthis behavior (Black Racers, for example), Water Snakesdo not.

A heat-sensing “pit” presentin Water Moccasins is absentin Water Snakes like theBanded Water Snake below.Water Moccasins also haveelliptical pupils, whereas non-

venomous WaterSnakes haveround pupils.

Head shape and features...The shape of the head is not a reliable way to differentiatethese species since Water Snakes can flare out their head

Double scale rows

WATER SNAKE

Single scale row

WATER MOCCASINFor additional information on snakes pleasecontact: Georgia Department of Natural Resources

Nongame-Endangered Wildlife Program116 Rum Creek DriveForsyth, GA 31029(478) 994-1438