Rattlesnake is Amazing Snake

Rattlesnakes are a group of venomous snakes of the genera Crotalus and Sistrurus of the subfamily Crotalinae ("pit vipers"). The 32 known species of rattlesnakes have between 65 and 70 subspecies, all native to the Americas, ranging from southern Alberta and southern British Columbia in Canada to Central Argentina.

Rattlesnakes are predators that live in a wide array of habitats, hunting small animals such as birds and rodents. They kill their prey with a venomous bite, rather than by constricting. All rattlesnakes possess a set of fangs with which they inject large quantities of hemotoxic venom. The venom travels through the bloodstream, destroying tissue and causing swelling, internal bleeding, and intense pain. Some species, such as the tiger rattlesnake and the Mojave rattlesnake, additionally possess aneurotoxic component in their venom that causes paralysis and other nervous system symptoms.

The threat of envenomation, advertised by the loud shaking of the titular noisemaker ("rattle") at the end of their tails, deters many predators. However, rattlesnakes fall prey to hawks, weasels, king snakes, and a variety of other species. Rattlesnakes are heavily preyed upon as neonates, while they are still weak and mentally immature. Large numbers of rattlesnakes are killed by humans. Rattlesnake populations in many areas are severely threatened by habitat destruction, poaching, and extermination campaigns.

Rattlesnake bites are the leading cause of snakebite injuries in North America. However, rattlesnakes rarely bite unless provoked or threatened; if treated promptly, the bites are rarely fatal.

Prey

Rattlesnakes consume mice, rats, small birds and other small animals. They lie in wait for their prey, or hunt for it in holes. The prey is killed quickly with a venomous bite as opposed to constricting. If the bitten prey moves away before dying, the rattlesnake can follow it by its scent.When it locates the fallen prey, it checks for signs of life by prodding with its snout, flicking its tongue, and using its sense of smell. Once the prey has become incapacitated, the rattlesnake locates its head by odors emitted from the mouth. The prey is then ingested head-first, which allows wings and limbs to fold at the joints in a manner which minimizes the girth of the meal. The gastric fluids of rattlesnakes are extremely powerful, allowing for the digestion of bone, as well as flesh. Optimal digestion occurs when the snake maintains a body temperature between 80 and 85°F (25 and 29°C). If the prey is small, the rattlesnake often continues hunting. If it was an adequate meal, the snake finds a warm, safe location in which to coil up and rest until the prey is digested.

Rattlesnakes are believed to require at least their own body weight in water annually to remain hydrated. The method in which they drink depends on the water source. In larger bodies of water (streams, ponds, etc.), they submerge their heads and ingest water by opening and closing their jaws, which sucks in water. If drinking dew, or drinking from small puddles, they sip the liquid either by capillary action or by flattening and flooding their lower jaws

 

Predators

Newborn rattlesnakes are heavily preyed upon by a variety of species, including ravens, crows, roadrunners, raccoons, opossums, skunks, coyotes, weasels, whipsnakes,kingsnakes, and racers. Neonates of the smaller crotaline species are frequently killed and eaten by small predatory birds such as jays, kingfishers, and shrikes. Some species ofants in the genus Formica are known to prey upon neonates, and Solenopsis invicta (fire ants) likely do, as well. On occasion, hungry adult rattlesnakes cannibalize neonates. The small proportion (often as few as 20%) of rattlesnakes that make it to their second year are heavily preyed upon by a variety of larger predators including coyotes, eagles,hawks, owls, feral pigs, badgers, indigo snakes, and kingsnakes.

The common kingsnake (Lampropeltis getula), a constrictor, is immune to the venom of rattlesnakes and other vipers, and rattlesnakes form part of its natural diet. Rattlesnakes sense kingsnakes' presence by their odor. When they realize a kingsnake is nearby, they begin enacting a set of defensive postures known as "body bridging". Unlike its normal erect and coiled defensive-striking posture, the rattlesnake keeps its head low to the ground in an attempt to prevent the kingsnake from gaining a hold of it (the head being the first part of the rattlesnake to be ingested). The rattlesnake jerks its body about, while bridging its back upwards, forming an elevated coil which faces the kingsnake. The elevated coil is used to strike the attacker, and is also used to shield the head from the kingsnake.

Range and Habitat

Rattlesnakes are native to the Americas, living in diverse habitats from southwestern Canada to central Argentina. The large majority of species live in the American Southwest and Mexico. Four species may be found east of the Mississippi river, and two in South America. In the United States, the states with the most types of rattlesnakes are Texas and Arizona.

Rattlesnakes are found in almost every type of habitat capable of supporting terrestrial ectothermic vertebrates, but individual species can have extremely specific habitat requirements, only able to live within certain plant associations in a narrow range of altitudes. Most species live near open, rocky areas. Rocks offer them cover from predators, plentiful prey (e.g. rodents, lizards, insects, etc. that live amidst the rocks), and open basking areas. However, rattlesnakes can also be found in a wide variety of other habitats including prairies, marshes, deserts, and forests. Rattlesnakes prefer a temperature range between 80 and 90°F (26 and 32°C), but can survive temperatures below freezing, recovering from brief exposure to temperatures as low as 4°F (-16°C), and surviving for several days in temperatures as low as 37°F (3°C).

Evidence has been collected to show the most probable ancestral area of rattlesnakes is the Sierra Madre Occidental region in Mexico. This same study found the most probable vegetation or habitat of the ancestral area to be pine-oak forests. Feeding habits play an important ecological role by limiting the size of rodent populations, which prevents crop damage and stabilizes ecosystems.