The common garter snake is a widespread, non-venomous reptile native to North America, often found in moist environments near water sources. While these snakes are frequently observed on land, they actively seek out surface moisture for hydration. Yes, garter snakes do drink water. This need for external water is tied to their physiology and the unique way they process and conserve bodily fluids.
The Mechanics of Snake Drinking
Garter snakes, like all snakes, cannot drink by sucking or lapping water due to the absence of cheek muscles. Instead, they employ a specialized mechanism to ingest surface water. When a snake finds a source of water, it lowers its head and submerges the lower jaw.
The lower jaw contains folds of soft tissue with tiny, sponge-like gaps. As the snake dips its mouth, these folds unfurl, and the gaps fill with water through capillary action, much like a sponge absorbing liquid. The snake then uses muscular contractions in its throat and jaw to squeeze the water from these tissue folds and swallow it.
Garter snakes also utilize environmental moisture, frequently drinking droplets that collect on their scales, rocks, or vegetation after rain or heavy dew. This ability to harvest moisture from diverse surfaces is important for species not always near standing bodies of water.
Hydration Through Diet and Metabolism
While surface drinking is necessary, garter snakes obtain a substantial portion of their fluid requirements from their carnivorous diet. Their primary prey—including earthworms, slugs, amphibians, and small fish—are naturally high in moisture content. For instance, earthworms can be over 80% water by mass, providing a fluid boost with every meal.
This high-moisture diet reduces the frequency and volume of water the snake must drink externally. Beyond the water contained within their prey, snakes also generate metabolic water. This water is produced internally as a byproduct when the snake’s body breaks down food during digestion and energy conversion.
Reptiles possess physiological adaptations to conserve water, minimizing loss through waste. Unlike mammals, which excrete nitrogenous waste as water-intensive urea, snakes excrete it as uric acid, a semi-solid paste that requires very little water for elimination. This combination of dietary intake, metabolic production, and retention allows garter snakes to survive periods when fresh water is less available.
Environmental Influences on Water Needs
The frequency with which a garter snake needs to actively drink is largely determined by external environmental conditions. As ectotherms, their body temperature fluctuates with their surroundings, meaning high ambient temperatures increase their need for hydration. When temperatures rise, snakes lose water more rapidly through respiration and evaporation from the skin, compelling them to seek water for replenishment and sometimes for thermoregulation through soaking.
Drought conditions or a lack of recent rainfall drastically increase the need for a water source, as the environmental moisture that collects on surfaces disappears quickly. Conversely, during periods of brumation (the reptilian equivalent of hibernation), the snake’s metabolic rate drops dramatically. This reduced internal activity means that water needs are significantly lowered, allowing them to remain hydrated on stored reserves and metabolic water for extended periods.
Garter snakes are often found near water because it represents a reliable resource for both hydration and a consistent food supply. Their semi-aquatic nature and adaptable hydration strategies enable them to thrive across a wide range of habitats, from damp meadows to suburban gardens.