Garter snakes emerging from their winter brumation den under a stone wall
Photo: Kevin McKeon
Garter Snakes Waking Up, Smelling the Critters
By Kevin McKeon, Maine Master Naturalist
Fossil records show that snakes slithered into existence about 167 million years ago, descending from the 250-million-year-old lizards that managed to survive Earth’s largest extinction event, sometimes referred to as “The Great Dying”, an event comparable to current ongoing Earth conditions. Here’s Dr. Lee Kump, Pennsylvania State University’s dean of the Earth and Mineral Sciences College and professor of geosciences:
“The Permian-Triassic mass extinction provides a stark reminder of the consequences of rapid carbon dioxide emissions…. Today, we see human activities driving similar processes at an even faster rate. The geological record shows that once these tipping points are reached, the cascading effects on ecosystems can last for millions of years.”
OK, now about snakes. Estimates vary widely, but scientists believe that there are about 3,500-4,000 snake species. Nine of those live in Maine. First, let’s clear something up: venomous vs. poisonous. Venomous snakes inject their toxins via grooved or hollow fangs; a poisonous snake releases its toxin through an adversary either contacting its skin or eating it. No Maine snakes are considered venomous, poisonous, or even dangerous. But let’s talk a bit about garter snakes.
Garter snakes are one of the least dangerous snakes in the world. When threatened, they’ll release a foul-smelling musk and slither away rather than bite — posing little to no risk to humans in our area. Their mild venom serves to stupefy their small prey: slugs, snails, and small amphibians. But they can be considered poisonous due to the prey they sometimes eat, though not in our area. This is where the rough-skinned newt, Taricha granulosa, adds an interesting story to the garter snake’s allure.
The rough-skinned newt contains the same deadly neurotoxin in its skin as the puffer fish. Large quantities are present in this newt, and some garter snakes have the unique ability to safely ingest these newts. Garters can determine toxin levels of the deadly newt by partially swallowing the newt, detecting whether or not the toxic levels are manageable, and then either swallowing or releasing it! If the newt is eaten, the toxins accumulate in the snake’s liver with enough toxicity to kill the unfortunate bird or mammal predator that eats it. Garter snakes are the only known animals that can eat a rough-skinned newt and survive.
But having said all this, almost all rough-skinned newts live west of the Cascade Mountains, in a small area along the northwestern United States Pacific coast, and not around Maine. The closest population of these newts to Mainers is in Idaho, probably the result of a pet release introduction. So, garter snakes around here are harmless to people.
In mid-April, snakes are beginning to awaken from their brumation, a type of winter dormancy, where they share body heat with other snakes — sometimes dozens of them — in an underground den called a hibernaculum. Since they do not dig, they find suitable dens in stone walls and piles, and in the homes of other critters, like woodchucks and chipmunks. Hibernacula are often re-visited for years and shared with other snake species. And because reptiles don’t usually eat when their body temperatures drop below 60º F, these winter homes are even shared among snakes that eat each other.
Emerging from brumation, snakes seek heat to bask their cold-blooded (ectothermic) bodies. Snakes basking can often be seen by observant, slower-walking trail users along sunny areas — especially on gravel sections of our trails, warming their bodies and increasing their mobility and foraging capabilities.
Snakes’ sense of smell is centered in their tongues. A small notch in their lips allows their tongues to stick out and collect scents and small bugs. The tongue’s fork then contacts the Jacobson’s organ on the roof of the mouth — a sensory organ that acts like our noses. Snakes also sense their surroundings through ground vibrations and can determine the size and location of either food or danger. Snakes are at home everywhere in Maine, on land and in water. They are carnivores, eating earthworms, small birds and rodents, insects, eggs, smaller snakes and fish. They play an important role in ecosystems, helping to control pests and ticks, protecting crops and mitigating diseases, while helping to sustain a biodiverse landscape.
In Northeastern Native American folklore, snakes hold significant symbolism, representing fertility and healing; snakes are also linked with water, rain, thunder, and lightning. Stone monuments are peppered throughout New England and the United States built by indigenous tribes to glorify these incredible creatures and are still occasionally found in the Maine woods. So, if you happen across a short, rather nondescript stone wall or structure while walking along trails and among the woods, imagine the possibility of it being a sacred tribute to a snake, turtle, or other creature of our landscapes.
Winter dormancy: https://sanfordspringvalenews.com/sleep-comes-in-many-forms/
Editor’s note: Did you see something unusual last time you were out in the woods? Were you puzzled or surprised by something you saw? Ask our “Out in the Woods” columnist Kevin McKeon. He’ll be happy to investigate and try to answer your questions. Email him directly at: kpm@metrocast.net
The post Out in the Woods appeared first on Sanford Springvale News.
