The question of whether a banded snake is dangerous often causes confusion, stemming from the specific terminology used to describe how a toxin is delivered. Dangerous snakes are classified as venomous because they actively inject toxins, called venom, typically through a bite or specialized fangs. Conversely, a poisonous animal delivers its toxin passively, such as when it is ingested or absorbed through the skin, like a poison dart frog. The striped or ringed patterns, often called “banding,” are a visual trait common to many snake species, both harmless and highly dangerous, making quick identification difficult.
Banding Is Not a Reliable Indicator of Danger
The presence of bright, contrasting bands on a snake’s body is not a reliable indicator of a venomous species. This vibrant coloration, known as aposematism, works as a warning signal to predators that the animal is either toxic or difficult to consume. However, this warning signal is often exploited by harmless species through a survival strategy called Batesian mimicry.
Batesian mimicry occurs when a non-toxic species, the mimic, evolves to resemble a dangerous one, the model, thereby deterring predators. For example, the non-venomous Scarlet Kingsnake has developed a pattern similar to the highly venomous Coral Snake, gaining protection. The banded pattern is a survival mechanism, not a universal guarantee of toxicity, requiring closer inspection of the color sequence for proper identification.
Identifying the Highly Venomous Coral Snakes
In North America, the most prominent example of a dangerous banded snake is the Coral Snake (Micrurus or Micruroides). This snake is a member of the Elapidae family, which includes cobras, and possesses a potent neurotoxic venom that affects the nervous system and can cause paralysis. The Coral Snake is characterized by distinct, alternating rings of red, yellow, and black that completely encircle its slender body.
The specific arrangement of these rings is the most important detail for identification. In the Coral Snake, the wide red bands touch the narrow yellow bands. This pattern is the basis for the well-known mnemonic device: “Red touch yellow, kill a fellow.” The snake also typically has a black snout followed by a broad yellow band on its head.
Harmless Species That Mimic Dangerous Patterns
Several non-venomous snakes have evolved color patterns that closely resemble the Coral Snake, with the Scarlet Kingsnake (Lampropeltis elapsoides) and Milk Snake (Lampropeltis triangulum) being common mimics. These harmless snakes are constrictors that pose no venom risk to humans. Their mimicry is effective, granting them a defensive advantage against predators.
The crucial difference in the pattern of these mimics lies in the order of the rings. In the harmless Kingsnakes and Milk Snakes, the red bands always touch the black bands, not the yellow ones. This contrasting pattern is captured by the second half of the mnemonic: “Red touch black, friend of Jack.”
Safe Practices During Snake Encounters
The safest approach during any snake encounter is to assume the snake could be venomous and maintain a respectful distance. Never attempt to handle, capture, or harm a snake, as most bites occur when a person actively tries to interact with the animal. If a snake is encountered, slowly retreat and give it a wide berth; the snake will move away on its own if it does not feel threatened.
If a bite occurs, immediate medical attention is necessary, and the person should remain calm. Remove any jewelry or tight clothing near the bite site before swelling begins, and immobilize the affected limb below the level of the heart. Do not attempt to cut the wound, suck out the venom, apply a tourniquet, or use ice, as these actions can cause more harm.