It’s no secret that the Houston Zoo Reptile House staff love rattlesnakes… but why?  What do we know that you don’t?   For many people, the sight or sound of a rattlesnake results in sheer terror.  Yes, rattlesnakes are potentially dangerous due to their elegant venom delivery system, but they typically give you a warning well before they strike – why do you suppose that is?  Let’s touch on some rattlesnake physiology…


Eastern Diamond-backed Rattlesnake (Crotalus adamanteus)


Rattlesnakes are highly evolved animals.  Their skull is very delicate, having an open framework with fairly thin bones – compare this to a python, which has a reinforced, almost solid skull.  A python needs a heavy skull because they grab and hold their prey, which is often kicking and thrashing about (I can’t say I wouldn’t do the same). A rattlesnake relies on its venom to subdue its meal;  it bites and quickly lets go because a thrashing animal could do some serious and irreparable damage to the snake’s skull.  After envenomating its prey – a rodent for example – the rattlesnake then patiently waits for the venom to do its job.  At this point the rodent may have wandered off before dying, so the rattlesnake tracks it using some pretty cool high-tech equipment:  heat sensing pits (which form infrared images, allowing them to “see” in the dark) and a complex chemosensory system  (allowing them to “taste” their way around with great precision and accuracy).  Using these amazing built in tools, they can safely track the same rodent they bit a few minutes before and eat it in peace without any injury from a struggle.  Check out some amazing rattlesnake footage from David Attenborough’s BBC series “Life in Cold Blood” here.


Mojave Rattlesnake (Crotalus scutulatus)


So back to the rattle… when a rattlesnake rattles, it is threatened – something or someone has invaded its personal space.   Although most people are under the impression that ALL snakes are out to get them (especially rattlesnakes), this couldn’t be farther from the truth.   These snakes want absolutely nothing to do with us and will always flee if there is an escape route available.  An animal of our stature could easily kill a snake as small as a rattler – if a human were to accidentally step on one, that fragile skull I mentioned earlier would be crushed.  So if you threaten a rattlesnake (even by accident) and it has to protect itself, its rattle will send you a clear message:  Don’t tread on me!   This audible warning makes rattlesnakes pretty darn polite in my opinion…   But the real reason they give you fair warning is (again) they don’t want a confrontation and  they don’t want to waste venom on an enemy unless they are forced to.  Venom takes a lot of energy to make and the snake would rather use it for its intended purpose (to catch food).  So,if you ever hear/see an agitated rattlesnake in the wild, simply stop, stay calm, locate the snake and slowly back away from it until you are out of harms way.


Canebrake Rattlesnake (Crotalus horridus)


Rattlesnakes are often misunderstood and underappreciated animals.  They are unique to the Americas and are found nowhere else in the world – the American Southwest and Mexico boast the highest diversity of species.  They have very caring courtship behaviors and give birth to live young; parental care has even been documented in some species. They have striking colors and markings yet blend in perfectly with their surroundings.  They play the very important role of  predator in many ecosystems and keep populations of other critters under control, while being a prey item themselves for other snakes and hawks.  And come on – they have RATTLES on the end of their tails!  How cool is that?!!



Those who care for rattlesnakes for a living will tell you that they are peaceful and curious animals.  Working with them on a daily basis allows us to get to know them as individuals – yep, they have distinct personalities and quirks just like every other animal!  Starting to see why we love rattlesnakes so much?  Hopefully you are beginning to understand why we want to protect them.

Rattlesnakes were once well respected and  even symbolized our great country in its infancy.  Now, hundreds of thousands of rattlesnakes are persecuted and needlessly killed every year.  Rattlesnake roundups – events in which these snakes are collected from the wild and slaughtered as a public spectacle – are a severe threat to rattlesnake populations in the state of Texas.  As a native Texan, I am painfully embarrassed that these events persist  – the animals are treated disrespectfully before they are killed (and they are ALL killed) and this sends a horrible message to event attendees, especially children.  Help us put an end to the killing and ask that these yearly festivals be changed to educational ones that advocate respect for nature – before it’s too late for the rattlesnakes of Texas.


Aruba Island Rattlesnake (Crotalus unicolor), the rarest rattlesnake on Earth. Photo: Jeff Whitlock


So take the time to learn more about the fascinating world of rattlesnakes and then spread the word – shout it from the rooftops!! RATTLESNAKES ROCK!!

Still don’t appreciate rattlesnakes?  Think the only good snake is a dead snake?  Hmm… I hope you don’t mind a few hundred rodent house guests because without snakes around, I can guarantee they’ll be moving in soon!



One Response to “Rattlesnakes Rock!”

  1. Was just in Aruba! Didn’t know they had their own rattlesnake! So cool!

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