The Copperhead (Agkistrodon contortrix) is one of the most common venomous snakes in North America. Its distinctive appearance often leads to the misidentification of many harmless species, which have evolved patterns and colors that mimic the Copperhead’s look. Accurately distinguishing between the Copperhead and its look-alikes is important for public safety and helps prevent the harm of beneficial native wildlife.
Distinctive Features of the Copperhead
The Copperhead is a pit viper, defined by a broad, triangular head that houses venom glands and powerful jaw muscles, giving it a distinct neck. Its coloration features a pale tan, pinkish-tan, or light brown base color, overlaid with a pattern of darker, reddish-brown crossbands. These dark bands are uniquely shaped like an hourglass, or sometimes described as a “Hershey’s Kiss,” narrowing significantly across the spine.
This species also has features common to all pit vipers, including heat-sensing pits located between the eye and the nostril. The eyes have vertical, elliptical pupils, often likened to a cat’s eye, and are set in a yellow or golden iris. Juvenile Copperheads possess a bright yellow or greenish tail tip, which is used in a behavior called caudal luring to attract small prey like frogs and lizards.
Common Copperhead Look-Alikes
The visual similarity between the Copperhead and other species is a frequent cause of mistaken identity, often leading to the killing of harmless snakes. The Northern Water Snake (Nerodia sipedon) is the most commonly confused species, especially when its patterns are obscured by moisture or age. Its habit of basking near water bodies, which Copperheads also do, contributes to the confusion.
The Eastern Milk Snake (Lampropeltis triangulum) is another common mimic, featuring a base color and blotches that can resemble the Copperhead’s pattern. Juvenile Rat Snakes (Pantherophis obsoletus) are also often mistaken for Copperheads due to their blotchy patterns on a gray background. These young snakes can flatten their heads when threatened, temporarily creating the triangular shape associated with pit vipers.
Crucial Distinctions for Identification
The most reliable way to differentiate a Copperhead involves examining the specific shape of its pattern. The Copperhead’s hourglass pattern is narrowest where it crosses the center of the back, creating a narrow, pale saddle of background color over the spine. In contrast, the blotches or bands on the Northern Water Snake and the juvenile Rat Snake are widest over the spine, forming simple dark saddles or blotches that do not pinch in the middle.
Examining the eyes and head shape also provides clear distinctions. Non-venomous snakes like the milk snake and water snake possess round pupils, unlike the Copperhead’s vertical slits. Non-venomous species have a slender head that aligns with the width of their neck, whereas the Copperhead has a bulky, triangular head clearly separated from a narrower neck. The bellies of non-venomous look-alikes like the Eastern Milk Snake often have a black and white checkerboard pattern, while the Copperhead’s belly is a solid off-white or cream color.
Safe Practices When Encountering Snakes
Encountering any snake requires a cautious approach, regardless of its identity. The safest practice is to maintain a minimum distance of six feet, which allows the snake to move away naturally without feeling threatened. Never attempt to handle, harass, or move a snake, even if you believe it to be harmless, as many non-venomous species will bite defensively.
Avoid placing hands or feet into dark, hidden areas like rock crevices, thick brush, or under logs where a snake might be resting. If a bite occurs, seek medical attention immediately by calling emergency services. Keep the bitten limb immobilized and below the level of the heart, and never attempt folk remedies like cutting the wound or applying a tourniquet.