Rattlesnakes are native to the U.S. They are one of only four snakes in the U.S. whose venom is dangerous to humans. The rattlesnake is a cold-blooded animal, relying on the heat from the sun and hot surfaces to maintain its body temperature.
Sixteen varieties of rattlesnake and numerous subspecies with various color and marking variations are found around the world. The rattlesnake is known as a pit viper, because of the two small pits beneath its nostrils that detect heat from its prey, according to Desert USA. The two pits allow the rattlesnake to accurately determine the size of its prey and its distance away. The average length of a rattlesnake is between 3 and 4 feet, with a rattlesnake residing in an area with abundant food reaching a length of around 5 feet. A rattlesnake can be identified by its jointed rattle at the end of the tail and its triangular head.
It is common for rattlesnakes to hibernate when the average temperature descends in the fall and winter months, commonly between November and April. During the hibernation season, rattlesnakes congregate in small groups for warmth. The grouping of rattlesnakes is known as a snake pit. The areas usually chosen by rattlesnakes for hibernation include rocky ledges at high elevations, from which snakes may occasionally venture into open areas to bask on warm, sunny days.
As temperatures rise, rattlesnakes venture out of their hibernation areas, but throughout the summer remain around 1 mile from the hibernation area. For the first few days following hibernation, the rattlesnake remains close to the hibernation area before venturing farther to find shelter and food. During summer months, rattlesnakes tend to hunt small rodents and birds during the nighttime when temperatures are cooler, and spend the days coiled under rocks, bushes and in wood piles to shelter from the sun.
During the warm summer months, it is not common to find rattlesnakes moving around habited areas, although during the evening many can be seen finding warmth on asphalt roads and paved concrete areas. When the temperature is hot in the daytime, rattlesnakes can often be found seeking shelter in areas such as garages, basements, crawl spaces and beneath patio furniture to find shelter from the heat of the sun. The most common time to see rattlesnakes is during the migration seasons as snakes move toward their hibernation areas during the fall and when they emerge from hibernation in the spring.