The vast wilderness of Alaska, known for its majestic landscapes and unique wildlife, often sparks curiosity about its inhabitants. Among the common inquiries is whether this northern state is home to any snake species, particularly those that might pose a danger to humans.
The Simple Answer
Alaska stands out as one of the few places globally, and within the United States, that does not have any native venomous snakes.
Why Alaska Lacks Venomous Snakes
The primary reason for Alaska’s lack of native snake populations is its harsh climate. Snakes are ectothermic, meaning they rely on external heat sources, like the sun, to regulate their body temperature. Alaska’s long, dark, and frigid winters do not provide the consistent warmth necessary for snakes to survive, hunt, digest food, or reproduce effectively. The lack of sunlight during the colder months further hinders a snake’s ability to absorb the heat needed for basic bodily functions.
Furthermore, the presence of permafrost, or permanently frozen ground, creates additional challenges. Even if snakes could find shelter for hibernation, the ground can freeze solid, making it difficult to locate suitable sites and potentially leading to freezing temperatures within those shelters. Alaska’s geographical isolation, separated from the contiguous United States by Canada, and its history of extensive glaciation also contribute to this absence. These factors have historically acted as barriers, preventing snake species from migrating northward and establishing sustainable populations.
Reptiles and Amphibians Found in Alaska
Despite the absence of native snakes, Alaska does host a limited number of other reptile and amphibian species. The state’s climate restricts the diversity of these cold-blooded creatures. Amphibians found in Alaska include the Wood Frog, Columbia Spotted Frog, Western Toad, Rough-skin Newt, Long-toed Salamander, and Northwestern Salamander. Regarding reptiles, the only native species are certain sea turtles, such as the Leatherback, Green, Loggerhead, and Olive Ridley sea turtles, though sightings are rare.
The Common Garter Snake (Thamnophis sirtalis) is occasionally sighted in southeastern Alaska, likely due to its proximity to British Columbia. However, this species is not considered dangerous to humans. While garter snakes produce a mild neurotoxic venom, they lack an effective delivery mechanism to cause significant harm to people. Bites are generally comparable to a bee sting, resulting in only minor irritation, such as mild swelling or itching. Garter snakes can also become poisonous by consuming toxic prey, such as certain newts, and retaining those toxins in their liver.