Common Watersnake
Nerodia sipedon • Order: Squamata; Suborder: Serpentes; Family: Colubridae; Subfamily: Natricinae; Genus: Nerodia; Species: sipedon
Venomous Status
Non-venomous; aglyphous (lacking specialized fangs).
Danger Level
Harmless - Low Risk. While they are famously defensive and will bite repeatedly if handled, they pose no toxicological threat to humans.
Geographic Range
Eastern and central North America, ranging from southern Ontario and Quebec south to North Carolina and west to Colorado and the Mississippi River. Found throughout Maryland, including the Eastern Shore and Deal Island.
Conservation Status
Least Concern (IUCN). They are abundant and resilient, though they suffer high mortality from being mistaken for venomous Cottonmouths.
Physical Description
A heavy-bodied snake with strongly keeled scales. Coloration ranges from tan to grayish-brown with dark brown or reddish crossbands near the head that break into alternating dorsal and lateral blotches further down the body. The specimen in the image appears heavily charred or blackened by fire, but the robust body and keeled scales are characteristic of the genus.
Size & Dimensions
Typically ranges from 24 to 42 inches (61–107 cm); the record is approximately 59 inches. This specimen appears to be a mature adult based on its girth.
Habitat
Highly aquatic; commonly found in freshwater and brackish environments including marshes, ponds, lakes, rivers, and coastal islands. They are often seen basking on logs or rocks near the water's edge.
Behavior & Temperament
Very defensive. When threatened, they often flatten their bodies and heads to appear larger, release a foul-smelling musk, and strike repeatedly. They are primarily diurnal but can be active at night during hot summer months.
Diet & Feeding
Generalist carnivores focusing on fish and amphibians (frogs, toads, salamanders). They are active foragers that swallow prey alive without constriction.
Reproduction
Viviparous (gives birth to live young) rather than laying eggs. Birthing usually occurs in late summer or early autumn, with litters typically ranging from 15 to 30 neonates.
Venom & Safety
Venom Type
Non-venomous - no medically significant venom. However, their saliva contains mild anticoagulants that may cause a bite to bleed profusely.
First Aid Advice
Wash the bite area thoroughly with soap and water to prevent infection. Apply pressure if bleeding persists due to anticoagulants in the saliva. Seek medical attention if signs of infection occur.
Look-alikes
Commonly confused with the Northern Cottonmouth (Agkistrodon piscivorus). Distinguishable by round pupils (Cottonmouths have vertical slits), the absence of heat-sensing pits, and double-rowed subcaudal scales.
Conservation Status
Least Concern (IUCN). They are abundant and resilient, though they suffer high mortality from being mistaken for venomous Cottonmouths.
Cultural Significance
Often persecuted due to their aggressive appearance and resemblance to venomous species. Ecologically, they are vital for controlling fish and amphibian populations and serve as a food source for larger predators.
Notable Features
This specific specimen has notable heat damage or charring, likely having perished in a fire, as evidenced by the burnt log and background. They are known for their ability to tolerate brackish water better than many other freshwater snakes.
Notes
Deal island, md