My Kind of Diamonds Have Rattles
Imagine that you’re out exploring the desert of the southwestern United States when all of a sudden you hear the infamous sound that every western movie has associated with the biome, the warning rattle of a frightened snake. I grew up in the middle of nowhere in Southern California, and every year when spring returned bringing with it warmth to the landscape my parents reminded me it was time to watch out for snakes and always listen for rattles to stay safe. Rattlesnakes were just a part of growing up in a sort of scrubland, and I have developed a deep love and respect for these amazing creatures. The species that I remember seeing the most in my own backyard as I grew up was the western diamondback rattlesnake, and today I would like to shed some light on this misunderstood animal.
Western diamondback rattlesnakes are a common species found throughout the southwestern United States and into central Mexico. They can be found in the deserts, scrubland, and chaparrals, or more simply, the hot and dry habitats within their range. They avoid the heat during the day by being primarily nocturnal, or active at night, which is common among most desert species. If they are found out during the day, they can be recognized by their triangular-shaped head, plump body sporting a brown diamond pattern down their back, black and white bands near their rattles, and darker markings near their eyes.
Photo Credit: John Hardison via flickr
These snakes average 4-6 feet in length and can live upwards of twenty years in the wild, and don’t hit sexual maturity until around three years of age. When western diamondback rattlesnakes do reproduce the males participate in a “dance” (I have linked a video of this below) that serves as a nonlethal form of combat to determine which participant will win the right to mate with a nearby female. After a gestation period of 167, the female will give birth to 10-20 live young encased in a membrane over a period of 3-5 hours. The young sometimes stay with their mother for up to a day, but there is no real maternal care beyond that point in the rattlesnake world, and there is a high mortality rate for newborns. Rattlesnakes are born equipped to take care of themselves and lead a solitary life essentially from birth.
A major part of a western diamondback rattlesnake’s equipment for survival is their venom because it is not only the way they subdue their prey, it is their last line of defense if their warning rattle does not scare off a threat. Their infamous venom is hemotoxic, meaning it attacks the blood and is injected through two hollow fangs that can be replaced if in the event that they are damaged during the snake’s life. Adult rattlesnakes can also control the amount of venom they inject, and it is possible for them to deliver what is known as a “dry bite” with no venom injected at all. It is unclear when they begin to control the venom they inject, but this is likely the reason very young individuals are commonly said to be more “dangerous” than adults despite there being no difference in the overall toxicity of their venom.
Rattlesnake rattling in a studio setting. Credit: Kory Roberts via flickr
Biting however is a last line of defense and rattlesnakes are best known for the sound of the rattle that adorns the tip op their tail. This particular feat of evolution produces a sound that wards off would-be predators by advertising the toxic danger that is hidden within their mouths. They make this sound by shaking their tail rapidly and can cycle their rattle 40-60 times a second. Their rattle does gain a new section with every shed so older individuals do have larger rattles, however, they cannot be aged by counting the sections of the rattle because they shed several times a year and lose older sections of the rattle periodically.
Western diamondback rattlesnakes are a common species to find in educational facilities because they are an easier species of rattlesnake to raise in captivity, and play an important role in snake conservation and research. They are often used in demonstrations and their venom is common in the production of antivenom and venom research. Besides their roles in a captive setting, rattlesnakes feed primarily on rodents that are considered agricultural pests and may carry diseases that can be spread to humans. They are also culturally important to the Native Americans that encountered them and can be found in lore and traditional artwork.
These snakes are a beautiful member of the desert ecosystem and have unfortunately been given a bad reputation by modern media. Next time you find yourself face to face with one of these animals, just back away and allow them to slither off into the brush.
Rattlesnake Mating Dance:
https://www.youtube.com/watch?v=U8rQO-9J5Zg
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