The terms “venomous” and “poisonous” are often mistakenly used interchangeably, but they describe different ways toxins are delivered. Venomous animals inject toxins, typically through a bite or sting, like rattlesnakes or cobras using fangs. In contrast, an animal is poisonous if it contains toxins that are harmful when ingested or absorbed through touch. For example, certain frogs or plants are poisonous.
While most snakes are venomous, not poisonous, rare exceptions exist. Some garter snakes, for instance, can become poisonous by absorbing toxins from their prey, such as newts, which makes them unpalatable to predators if eaten. However, this does not mean they are dangerous to humans through a bite.
Identifying Common Black and Yellow Striped Snakes
Several non-venomous snake species in North America exhibit black bodies with yellow stripes, leading to misidentification and alarm. Among the most common are garter snakes, ribbon snakes, and certain kingsnakes. These species are harmless to humans, often relying on their appearance to deter predators.
Garter snakes (genus Thamnophis) are widespread across North America and have three light-colored stripes, typically yellow, running the length of their dark bodies. Their body color can range from black to brown or gray, and the stripes may also be white, green, or brown. Garter snakes have keeled scales. They are often found in gardens, near water sources, and in various habitats.
Ribbon snakes (Thamnophis sauritus) are closely related to garter snakes but are more slender with longer tails. They have three yellow or cream-colored stripes against a dark green, brown, or black background. A distinguishing feature of ribbon snakes is a white marking in front of each eye, which is absent in garter snakes. These semi-aquatic snakes are often found near ponds, streams, and wetlands, where they hunt small fish and amphibians.
Eastern kingsnakes (Lampropeltis getula) display a black body with yellow markings, forming a chain-like pattern of thin white or yellow bars. These constrictors are known for their ability to eat other snakes, including venomous species, as they are immune to their venom. Kingsnakes are found in diverse habitats, including forests, fields, and suburban areas, often seeking refuge under objects.
Encountering Snakes Safely
Encountering a snake can be startling, but snakes are not aggressive and prefer to avoid human interaction. If you come across a snake, remain calm and maintain a safe distance. Avoid making sudden movements that might startle the snake, and allow it space to move away on its own. Never attempt to handle, provoke, or harm a snake, even if it appears non-venomous, as any snake may bite if it feels threatened.
To reduce the likelihood of snakes around your home, you can make your property less appealing to them. This involves removing potential hiding spots such as overgrown vegetation, tall grass, woodpiles, rock piles, and other debris. Sealing any cracks or openings in your home’s foundation and around pipes can prevent snakes from entering structures. Controlling rodent populations and removing standing water can limit food and water sources that attract snakes. If a snake is inside your house, you can gently herd it outdoors using a broom, or cover it with a pail if it’s small, then contact a professional for removal.