The sidewinder is a pale, sand-colored snake that also may appear to look pinkish and yellow. They have light and dark patches along the back and speckles along the sides. The sidewinder has a wide triangular head, with a narrow neck that expands into a thick body. They have a short brown or black tail, that is connected to a small rattle.The sidewinder is the only snake that has a horn-shaped scales bulging out above their eye, which is how they get their nickname, the "Horned Rattlesnake". Also near their eyes, on the side of their head, they have holes called pits or hollows that are heat sensors that detect warm-blooded creatures. Adults average 30 inches in length, however females are usually larger than males so there is some sexual dimorphism.
The sidewinder is the fastest of rattlesnakes because it has a unique way of moving. The sindwinder pulls itself over the ground in a constant direction of S- or J-shaped loops. This helps the snake catch their prey faster and helps keep their body from touching the hot desert surface when traveling.
The subspecies of the sidewinder are the Mojave Desert Sidewinder. the Sonoran Sidewinder, and the Colorado Desert Sidewinder.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
The sidewinder is not that big of a threat towards humans, because when they bite, they only release venom that will kill a creature that weighs 30 pounds. However, sidewinder venom causes swelling, uncomfortableness, and sickness.
The sidewinder provides snakeskin leather for boots and accessories, and anti-venom for medical purposes.
The sidewinder is a carnivore. Their diet consists of lizards, small mammals like Kangaroo rats and pocket mice, other rodents that burrow, and sometimes birds. The pit organs are used to help find warm blooded animals to prey on. Sidewinders are the most nocturnal of rattlesnakes, so at night, they randomly wander over the desert until they find a place to burrow underneath the sand to hide. The following day they they stay burrowed until they find a prey to strike and feed. They kill their prey by hunting them down with their sidewinding moovement, then they strike their prey by biting them and releasing poisonous venom into the prey. After they bite a warm blooded animal, such as a rodent, they release it to track it down later. However, lizards are held until the venom takes effect.
The sidewinder ranges from the Mojave and sonoran deserts of southeastern California, western Arizona, southern Nevada, and southwestern Utah. Sidewinders are often found in arid deserts, flatlands, loose, sandy washes, hard pan flats, and rocky areas below 5,000 feet. Sidewinders are also common ammong hummoks that are topped with creosote where their food source of kangaroo rats and other rodents live.This is the smallest and least dangerous snake in Nevada. However, this is the most common snake in the Las Vegas Valley. In Las Vegas, they are fairly common on the lower slopes of alluvial fans.
Sidewinders are often found in arid deserts, flatlands, loose, sandy washes, hard pan flats, and rocky areas below 5,000 feet. Sidewinders are also common ammong hummoks that are topped with creosote where their food source of kangaroo rats and other rodents live.This is the smallest and least dangerous snake in Nevada. However, this is the most common snake in the Las Vegas Valley. In Las Vegas, they are fairly common on the lower slopes of alluvial fans.
Terrestrial Biomes: desert or dune
Average lifespan
Status: captivity: 27.3 years.
Sidewinders give birth to live young. The two most important events in a sidewinders calander are mating and birth. Some femals take a year off of breeding and only breed every other year. Some even rest for two years, if the food supply is scarce. Sidewinders mate in April through May and sometimes in fall. When the male and female mate, the male snake crawls along the female's back, rubbing her with his chin to stimulate or arouse her. The male then will wrap his tail around her tail and then will try to bring their clocqe together. The clocque is a little flap that is near tail which is designed for mating and reproduction. If the female wants to mate, she will lift her tail and allow him to mate with her. The snakes can be mating fo several hours, and if one of the snakes decides to move, the other is dragged along. Females might mate with the same male snake or a different male snake. In case their is a different male snake, the female has a good selection of genes for her young and inceases the chances that at least some of her young will fit to survive. Females give birth to 15-18 young in late summer to early fall. The young are born 6 to 8 inches long. The birth takes only 2 to 3 hours altogether. Within a few minutes after being born, the baby sidewinder escapes out of a thin transparent membrane. The young stay near their birth place for a few days and then they disappear and have no future contact with their mother or their littermates. The sidewinder does not migrate over long distances, so being in the some area with one of their littermates isn't unlikely.
The sidewinder's life span varies. Sidewinders can live up to 20 to 30 years in captivity. In the wild, many of their lives are cut short because of predation, diseases, or vehicle accidents.
The Sonoran Desert Sidewinder gets its name from the motion it uses to glide across hot surface sand. The Sidewinder lives in the dunes of the Sonoran Desert and must find a way to survive through the heat, so it using a sidewinding motion to ensure its body barely touches the sand.
The average size of the Sidewinder is 1.5 to 2 feet in length as an adult. The Sidewinder can be identified by its characteristics: the upturned scales above the snake’s eyes that resemble horns, it's dull sandy color patterned with dark marks on its back and sides, a dark cheek stripe running from eye to jaw on both sides of its head, and a few darker rings on its tail before its rattle. The Sidewinder has cat-like eyes and, like other pit vipers, a heat-sensing pit between its nostrils and eyes. The pit allows for the snake to be aware of predators and prey nearby.
The Sonoran Desert Sidewinder is a known predator as it is a venomous snake. Its diet consists of lizards, birds, small mammals, and other snakes. By waiting for its victims, the Sidewinder coils then attacks and injects venom through retractable fangs.
Sidewinder
Mojave desert sidewinder
Sonoran desert sidewinder
Colorado desert sidewinder
Southwestern USA (desert region of eastern California, southern Nevada, extreme southewestern Utah, and western Arizona) and northwestern Mexico (western Sonora and eastern Baja California) (McDiarmid et al., 1999).
Holotype: ANSP 7098
Type-locality: "borders of the Mohave river, and in the desert of the Mohve" [California] (McDiarmid et al., 1999).
Crotalus cerastes, known as the sidewinder, horned rattlesnake or sidewinder rattlesnake,[3] is a pit viper species belonging to the genus Crotalus (the rattlesnakes), and is found in the desert regions of the Southwestern United States and northwestern Mexico. Like all other pit vipers, it is venomous. Three subspecies are currently recognized.[4]
A small species, adult specimens measure between 43 and 76 cm (17 and 30 in) in length.[3] Most adults are 50–80 cm (19.5–31.5 in) in length.[5] The females are larger than the males, which is unusual for this group of snakes.[6]
Usually, 21 rows of keeled dorsal scales occur midbody.[3][7] Males have 141 or fewer ventral scales; females have 144 or fewer.[3] It is sometimes referred to as the horned rattlesnake because of the raised supraocular scales above its eyes. This adaptation may help shade the eyes or prevent sand drifting over them as the snake lies almost buried in it.[6]
The color pattern consists of a ground color that may be cream, buff, yellowish-brown, pink, or ash gray, overlaid with 28–47 dorsal blotches subrhombic or subelliptical in shape.[5] In the nominate subspecies, the belly is white and the proximal lobe of the rattle is brown in adults. Klauber and Neill describe the ability of this species to display different coloration depending on the temperature—a process known as metachrosis.[3]
Common names include sidewinder, horned rattlesnake, sidewinder rattlesnake, Mojave Desert sidewinder (for C. c. cerastes),[3] and sidewinder rattler.[8]
In the Southwestern United States, this species is found in the desert region of southeastern California, southern Nevada, southwestern Utah, and western Arizona. In northwestern Mexico, it is found in western Sonora and eastern Baja California.
This species is classified as least concern on the IUCN Red List (v3.1, 2001).[1] Species are listed as such due to their wide distribution, presumed large population, or because they are unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend was stable when assessed in 2007.[9]
The common name sidewinder alludes to its unusual form of locomotion, which is thought to give it traction on windblown desert sand, but this peculiar locomotor specialization is used on any substrate over which the sidewinder can move rapidly. As its body progresses over loose sand, it forms a letter J-shaped impression, with the tip of the hook pointing in the direction of travel. Sidewinding is also the primary mode of locomotion in other desert sand dwellers, such as the horned adder (Bitis caudalis) and Peringuey's adder (Bitis peringueyi), but many other snakes can assume this form of locomotion when on slick substrates (e.g., mud flats). Sidewinder rattlesnakes can use sidewinding to ascend sandy slopes by increasing the portion of the body in contact with the sand to match the reduced yielding force of the inclined sand, allowing them to ascend up to the maximum possible sand slope without slip.[10] In cybernetics, incorporating this control scheme into a snakebot can enable the robot to replicate sidewinding movement.[10] Activity range does not change with sex or body size.[11]
The species is nocturnal during hot months and diurnal during the cooler months of its activity period, which is roughly from November to March (probably longer in the southern part of its range).
Juveniles use their tails to attract lizard prey, a behavior termed "caudal luring". Adults lose this behavior as they make the transition from lizard prey to their primary diet of desert rodents, birds, and other snakes.[12] Sidewinder juveniles appear to mimic both life stages of lepidopterans in their luring motions. Their fast luring motions resemble the fluttering of a moth, and their slower tail movements resemble a caterpillar. Both movements have been observed to attract prey lizards.[13]
Neonatal sidewinders engage in a remarkable behavioral homeothermy that has not been observed in any other type of snake.[14] Following birth, the neonates mass together in their natal burrow. Most often, gravid females select an east-facing, small-diameter rodent burrow for giving birth. For the first week or so of their lives, neonatal sidewinders plug the entrance to this burrow during daylight hours, forming a dynamic multiple-individual mass that takes advantage of the hot exterior environment and the cool interior of the burrow to maintain an average aggregate temperature of 32 °C (the optimal temperature for shedding). The dynamic mass of neonates modifies the thermal environment at the burrow entrance such that the young can occupy a location that would ordinarily become lethally hot for an individual neonate (or even an adult).[14] Because of the constant movements of the neonates, the aggregate assumes stable temperature properties reminiscent of a homeothermic organism (i.e., maintains tight temperature tolerance ± 2 °C).
Females produce up to 18 young, with an average of about 10 per litter. Like most other viperids, the young are born enveloped in thin embryonic membranes, from which they emerge shortly after being expelled from the mother. The young stay with their mother in a burrow for 7–10 days, shed for the first time, then leave their natal burrow. During this time, the mother is thought to guard and protect them from predators.
Sidewinders mature at 2–3 years of age, are capable of reproducing annually, and give birth to live young. Some females skip reproductive opportunities.[15] Some might even skip two years if the food supply is scarce. Sidewinders mate in April through May and sometimes in fall. When the male and female mate, the male snake crawls along the female's back, rubbing her with his chin to stimulate or arouse her. The male then will wrap his tail around her tail, and then will try to bring their cloacae together. The cloaca is the posterior body opening through which snakes both excrete waste and reproduce. If the female wants to mate, she lifts her tail and allows him to mate with her. The snakes can mate for several hours, and if one of the snakes decides to move, the other is dragged along. Females might mate with several males in a season. Females give birth to five to 18 young in late summer to early fall. The young are born 6-8 inches long. The birth takes only 2–3 hours altogether. Within a few minutes of being born, the newborn sidewinder escapes from a thin, transparent membrane. The young stay at their natal burrow for 7–10 days until they shed,[14] and then they disappear and have no future contact with their mother or their littermates. While the density of sidewinders can be up to one individual per hectare, they rarely encounter each other except during mating season.[15]
Sidewinders have an extraordinarily accelerated lifecycle, with natural life expectancies of females of about 5 years.[15] Males may live quite a bit longer (maximum known natural lifespan of 13 years). Sidewinders can live more than 20 years when well fed in captivity (even females). Thus, energetics apparently factor heavily into natural female mortality,[15] whereas predation might be the primary pressure on males. In the wild, females often die of exhaustion after giving birth, but the lives of sidewinders are also cut short by predation, diseases, and vehicle encounters.
These snakes are venomous, but possess a weaker venom than many other rattlesnakes. This, together with the smaller size of their venom glands, makes them less dangerous than their larger relatives. Regardless, any rattlesnake bite can be fatal and should be taken seriously and medical attention sought immediately.
Norris (2004) lists these venom yields: 33 mg average and 63 mg maximum (Klauber, 1956), and 30 mg average and 80 mg maximum (Glenn & Straight, 1982).[16] Brown (1973) gives a venom yield of 33 mg (Klauber, 1956) and LD50 values for mice of 2.6 mg/kg IV, 3.0, 4.0, 2.3 mg/kg IP and 5.5 mg/kg SC for toxicity. With these figures, Brown calculated that the LD50 for an adult human being weighing 70 kg would be 385 mg (SC).[17]
Envenomation can cause pain, swelling, hemorrhagic bleb formation, and ecchymosis (i.e., bruising). Swelling, while not particularly severe, occasionally may involve entire limbs and the trunk. Envenomation's systemic symptoms include nausea, dizziness, chills, coagulopathy (blood disorders), and shock.[16] Klauber (1997) includes an account of a man who had been bitten on the first joint of the index finger of the right hand, with only a single fang penetrating. Although the bite was described as no more painful than a pin prick, a doctor was seen within about 25 minutes, and 10 cm3 of antivenin were administered. Within 2.5 hours, his entire arm was swollen and the pain was severe, "as if the arm were soaked in a bucket of boiling oil."[18]
Ovine-derived antivenom, CroFab, for North American pit viper envenomation, has been widely available since 2001. Consultation with a local expert or regional poison control center should be obtained before administering antivenom. The previous antivenin (ACP) is no longer manufactured.
Crotalus cerastes, known as the sidewinder, horned rattlesnake or sidewinder rattlesnake, is a pit viper species belonging to the genus Crotalus (the rattlesnakes), and is found in the desert regions of the Southwestern United States and northwestern Mexico. Like all other pit vipers, it is venomous. Three subspecies are currently recognized.
