Understanding whether a snake is venomous or non-venomous is important for safety. While many snakes are harmless, knowing key identification methods can help prevent dangerous situations and ensure appropriate reactions.
Physical Indicators of Venomous Snakes
Venomous snakes often exhibit physical characteristics that help distinguish them from non-venomous species, though these indicators are not always foolproof. Many venomous snakes, particularly pit vipers, commonly have a triangular or spade-shaped head, noticeably wider than their neck. This broadened head often accommodates their venom glands. Non-venomous snakes typically have more rounded heads.
Many venomous snakes, such as pit vipers, possess elliptical or slit-like pupils, similar to a cat’s eye. Most non-venomous snakes tend to have round pupils. However, this distinction is not universal, as some highly venomous snakes, like the coral snake, have round pupils.
A distinctive feature of pit vipers, which include rattlesnakes, copperheads, and cottonmouths, is the presence of heat-sensing pits. These small, dark openings are located between the nostril and the eye on each side of the head. These specialized organs allow pit vipers to detect the heat signature of warm-blooded prey. Rattlesnakes are also uniquely identified by the segmented rattle at the tip of their tail, which produces a buzzing sound as a warning.
Identifying Common Venomous Species
Specific venomous snake species found in North America possess unique characteristics.
Rattlesnakes
Rattlesnakes are widely recognized by their signature rattle at the end of their tail. They typically have a broad, triangular head and often display dark diamond or blotchy patterns along their thick, heavy bodies.
Copperheads
Copperheads are identifiable by their distinctive hourglass-shaped crossbands that are narrower along the spine and wider on the sides. Their coloration can vary from reddish-brown to tan, often with a coppery-colored head.
Cottonmouths
Cottonmouths, also known as water moccasins, are stout-bodied snakes with dark coloration, often with faint banding. A key defensive behavior is their tendency to open their mouths wide when threatened, revealing a stark white interior, which is how they earned the name “cottonmouth.”
Coral Snakes
Coral snakes are known for their vibrant and distinctive banding pattern of red, yellow (or white), and black. A common mnemonic rhyme, “red on yellow, kill a fellow; red on black, venom lack,” helps differentiate them from non-venomous mimics like the Scarlet Kingsnake. Unlike pit vipers, coral snakes have slender heads with little distinction from their necks.
Debunking Venomous Snake Myths
Many common beliefs about snake identification are inaccurate and can lead to dangerous assumptions.
One widespread myth is that all brightly colored snakes are venomous. While coral snakes are indeed venomous and vividly colored, some non-venomous snakes, such as certain kingsnakes, mimic their patterns for protection. Relying solely on color can lead to misidentification and potentially harmful encounters.
Another misconception is that all non-venomous snakes have round pupils and all venomous ones have elliptical pupils. While many pit vipers have elliptical pupils, venomous coral snakes have round pupils. Furthermore, in low light conditions, elliptical pupils can appear round as they expand.
The belief that head shape is always a reliable indicator is also misleading. While many venomous pit vipers do have broad, triangular heads due to their venom glands, some non-venomous snakes can flatten their heads when threatened to appear larger and more intimidating. Additionally, the myth that all water snakes are venomous is incorrect; many non-venomous water snake species exist.
Encountering a Snake: Safety First
When encountering a snake, prioritizing safety is important. Always assume the snake could be venomous and maintain a safe distance, generally at least five to six feet. Observe the snake from afar rather than attempting to approach or interact with it.
Avoid provoking a snake by attempting to catch, handle, or kill it. Most snake bites occur when people try to interfere with the animal. If a snake is encountered, back away slowly and calmly, allowing the snake ample space to move away.
In situations where a snake is found in a dangerous location, such as inside a home, contact local animal control or wildlife authorities. If a snake bite occurs, seek immediate medical attention. Remaining calm, keeping the bitten limb still and below the heart, and promptly going to a hospital are crucial steps.