Snakes are reptiles found in just about every part of the world living in deserts, forested regions, marshes, grasslands, and even bodies of water. Most snakes people encounter are harmless or considered beneficial because they feed on other common pests, including insects, amphibians, and small mammals like rodents. However, some snakes are venomous and put both humans and household pets in danger simply by being present.
Varying in size and color depending on the species, snakes found in the United States grow an average length of 3 feet (1 m) and may appear uniform in color or display patterns along their bodies. Common snake colors include black, green, brown, red, yellow, and orange. Venomous snakes, like rattlesnakes, cottonmouths, and copperheads, tend to have spade-shaped heads and elliptical pupils while nonvenomous snakes have rounded pupils and narrower heads. They are covered in scales that are leathery to the touch.
Snakes are cold-blooded creatures that need consistent sunlight in order to regulate their internal temperatures. As such, areas that experience extreme cold are inhabitable. Favored snake habitats include deserts, rocky terrain, forested regions, prairies, near ponds, around streams, and in close proximity to lakes.
When shelter and sources of food are scarce in their natural habitat, snakes enter homes and yards much more frequently. They can invade houses through cracks in building foundations, tears in window and door screens, and even through holes that serve electrical conduits and plumbing. Tall grasses in unkempt lawns provide snakes with ideal hiding and hunting grounds while stacks of firewood, brush, and junk piles offer the reptiles suitable shelter.
Most snakes are relatively harmless and actually flee from human interaction. When cornered, snakes hiss, coil, and either strike or bluff at offending parties. Though this can be frightening to experience, especially for young children and curious pets, no harm is typically caused. Nonvenomous snake bites are painful, but leave no lasting effects. In areas where venomous snakes live, approaching the reptiles is much more dangerous. Their bites can prove deadly if not treated immediately and properly.