Is a rattlesnake nocturnal?

Although many kinds of snakes and other reptiles are oviparous (lay eggs), rattlesnakes are viviparous (give birth to live young). 53 The female produces the ova ("eggs") in her ovaries, after which they pass through the body cavity and into one of her two oviducts. The ova are arranged in a continuous chain in a coiled section of the oviduct, known as the "tuba".

49 Male rattlesnakes have sexual organs known as hemipenes, located in the base of the tail. The hemipenis is retracted inside of the body when mating is not occurring. Females can store semen for months in internal recesses known as spermathecae, which permits them to mate during the fall, but not fertilize the ova until the following spring.

Rattlesnakes generally take several years to mature, and females usually reproduce only once every three years. Some rattlesnake species hibernate in the colder winter months. They often gather together for hibernation in very large numbers (sometimes over 1,000 snakes), huddling together inside underground "rattlesnake dens" or hibernacula.

5556 Rattlesnakes will regularly share their winter burrows with a wide variety of other species (such as turtles, small mammals, invertebrates, and other types of snakes). Rattlesnakes often return to the same den, year after year, sometimes traveling several miles to get there. It is not known exactly how the rattlesnakes find their way back to the dens each year, but it has been hypothesized that they use a combination of pheromone trails and visual cues (e.g. Topography, celestial navigation, and solar orientation).

Species with long periods of hibernation tend to have much lower reproductive rates than those with shorter hibernation periods, or those that don't hibernate at all. Female timber rattlesnakes in high peaks in the Appalachian Mountains of New England reproduce every three years on average; the lance-headed rattlesnake (C. Polystictus), native to the warm climate of Mexico, reproduces annually.

Like most other snakes, rattlesnakes aestivate during very hot or dry periods, which is why they are very rarely seen during the hottest and driest months of summer. Rattlesnakes tend to avoid developed areas, preferring undisturbed, natural habitats. Rapid habitat destruction by humans, mass killings during events like rattlesnake round-ups, and deliberate extermination campaigns all pose severe threats to rattlesnake populations in many areas.

Several species of rattlesnakes, such as the timber rattler, massasauga, and canebrake rattlesnake are listed as threatened or endangered in many U.S. states. A very large number of rattlesnakes die from being run over by cars. In more heavily populated and trafficked areas, there have been increasing reports of rattlesnakes that do not rattle.

This phenomenon is commonly attributed to selective pressure by humans, who often kill the snakes when they are discovered. 61 Non-rattling snakes are more likely to go unnoticed, and therefore survive to reproduce offspring who, like themselves, are less likely to rattle. Rattlesnakes tend to avoid wide open spaces where they cannot hide from predators and will generally avoid humans if they are aware of their approach.

63 Rattlesnakes rarely bite unless they feel threatened or provoked. A majority of victims (~ 72%64) are males, often young and intoxicated. Approximately half of bites occur in cases where the victim saw the snake yet made no effort to move away.

Hikers and campers should avoid contact with rattlesnakes by remaining observant and not approaching the animals. Hikers should be particularly careful when negotiating fallen logs or boulders and when near rocky outcroppings and ledges where rattlesnakes may be hiding or sunning themselves. Snakes will occasionally sun themselves in the middle of an open trail so such areas are not the only places where they are encountered.

Hikers are advised to keep their distance when encountering a rattlesnake on a trail and allow the snake room to retreat. Caution is advised even when snakes are believed to be dead; rattlesnake heads can see, flick the tongue, and inflict venomous bites for up to an hour after being severed from the body. Rattlesnake bites are rarely fatal to humans if treated promptly.

31 An estimated 7,000 to 8,000 people are bitten by venomous snakes in the United States each year with approximately five deaths. 67 The most important factor in survival following a severe envenomation is the amount of time elapsed between the bite and treatment.