Summer’s here and outdoor enthusiasts are out in force—hiking, biking, camping, fishing, canoeing and more. Many are having unintentional encounters with the most misunderstood wildlife in the state—snakes. Many people are afraid of snakes, even people with a well-developed awareness of the environment and the natural world. This is unfortunate, since
most snakes are about as threatening to humans as the average chipmunk. People fear snakes without knowing much about them, so a bit of knowledge can turn a chance encounter into a wonderful wildlife viewing experience.
Snakes are out in great numbers in warm weather because they are somewhat “solar powered”. Like other reptiles, snakes are ectothermic, or “cold-blooded”, animals: their body temperature changes to the temperature of their surroundings. To compensate, these reptiles often bask in the sun on cool days and hide in the shade on hot days when their bodies are too warm. A snake that is too cool will be sluggish and not able to digest food properly. Because of this, snakes that live in Colorado must hibernate to survive the winter. Once it warms up, they have a bit of catching up to do.
Snakes serve an important function in nature. They eat mostly rodents, frogs, other snakes, fish or snails and are themselves a food source for hawks, owls, skunks, and other predators. Snakes may eat as much as 25 percent of the rodent population in an area—a huge benefit! All snakes swallow their food whole. While they do have teeth, the teeth are made for grabbing, hooking and holding their prey, not chewing. Snakes can absorb vibrations through the ground and determine the size of the prey or danger by its movements.
Hardly any snakes pose actual danger to humans. In Colorado, only 3 of our 28 species of snakes are venomous. Prairie rattlesnakes, midget faded rattlesnakes, and the smaller massasaugas (mas•sa•sau•ga) are pit vipers with rattles. Other physical characteristics distinguish pit vipers from non-venomous snakes.
Most snakes have oval-shaped heads and round pupils. Pit vipers have triangular–shaped heads, vertical, elliptical pupils and a pair of large pits between the eyes and nostrils. The pits are very sensitive to temperature. By comparing the messages received on the right and left sides, they are able to tell exactly where their warm-blooded prey is.
Snake skin is dry and durable, made up of overlapping scales of a horny material called keratin. This armor is nearly waterproof and protects snakes as they move over rough or hot surfaces. To grow, snakes shed their outer layer of skin several times a year. Before shedding takes place, a liquid is secreted between the old layer of skin and the new one beneath it. Right after shedding, snakes often have an iridescent gleam to their skin, which sometimes makes people think that they are wet or slimy.
Despite being legless, snake move quickly and efficiently. Snakes have between 100-400 vertebrae with as many ribs attached! Those bones are surrounded by strong muscles. Rough belly scales allow the snake to keep their grip on rough branches and to push off of surfaces when they need to move. Most travel in an s-shaped wave movement produced by alternately tightening and relaxing muscles along each side. Others progress in a straight line using belly scales. Sidewinders lift their bodies up and then force them down to move forward.
Snakes lack eyelids, so they can’t blink or close their eyes. Their eyes are protected by immobile, transparent scales. Because of this, even a sleeping snake, completely unaware of anyone’s presence, appears to be staring at the intruder.
Why are snakes always flicking their tongues? It is how they smell. They are picking up chemical signals from their surroundings. The chemical molecules that snakes collect with their tongue are inserted into the Jacobson’s organ inside the mouth; this organ then analyzes this information about the environment.
If you come across a snake in your travels this summer, take a few moments to observe and enjoy it. Of course, rule out that its one of the three venomous snakes. Then, stay still and watch. Make a note of some of its features so that you can identify it. How does it move? Is it solid or plain colored? Striped? Cross-banded? Blotched?
Download our Quick Key to Amphibians and Reptiles of Colorado 
. to help you identify snakes or pick up a copy at your nearest Division of Wildlife office.
Good luck snooping on snakes this summer!