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Tick, Rattle, and Roll
Timber rattlesnakes help control the spread of Lyme disease. Too bad they’re endangered.

The only good snake is a dead snake. At least, that’s what my high school friend said the time we went backpacking and he chopped a garter snake in half with a machete. He wiped the blade in the grass while the tiny, non-venomous, non-constricting snake writhed—the last twitches of a non-threat neutralized.

Most snakes are harmless to humans, but developing a healthy fear of them kept our ancestors from getting squeezed to death or suffering a painful—and occasionally lethal—bite. But we may want to fight this ingrained phobia. (I mean, who needs it anyway since some of us spend the weekend tucked safely in our condos watching Snake Man of Appalachia?) And we should definitely rethink our urge to kill these reptiles—if only because they help keep us safe from another scary biter: the tick. That’s right, a recent study finds that snakes help halt the spread of Lyme disease.

The science is pretty simple. The three species of bacteria (genus Borrelia) that carry Lyme disease tend to live in small rodents. When a tick sucks an infected rodent’s blood, it too becomes infected. And if that itty-bitty tick should someday sink its mouthparts into say … you or your beloved pet, there’s a chance it’ll slip its new host a shot of that same bacteria. The result? A health condition that causes fever, headaches, depression, joint pain, and heart and central nervous system damage.

But what could help stop this chain of infections? A healthy dose of rodent-loving rattlesnakes! A single timber rattler eats 2,500 to 4,500 ticks a year, according to a new study conducted by Edward Kabay, a recently graduated masters student in conservation biology at the University of Maryland. (Kabay presented these findings last week at the 98th Annual Meeting of the Ecological Society of America.) When a snake catches a field mouse infected with Lyme, it gobbles up everything: the messenger (the tick), the message-sender (the mouse), and the message itself (the bacteria).

“Snakes have very strong digestive juices, capable of digesting bone, hair, and tissue,” Kabay tells me. “Anything with a soft exoskeleton is going to get dissolved with the rest of the meal.”

Since not every Lyme-carrying tick infects a person, Kabay says we can’t really say how many human cases of the disease rattlesnakes prevent each year. But removing these predators from the ecosystem could literally come back to bite us.

Unfortunately, when it comes to these reptiles, many humans still invoke the edict of kill-or-be-killed. Six states across the south and southwest still sanction snake roundups that encourage hunters to turn in snakes for cash. (To catch the reptiles, hunters sometimes spray gasoline into burrows made by tortoises. Such dens are a common hideout for snakes as well as more than 350 other species, ranging from insects to small mammals, that often die as a result.) Meanwhile in the east, timber rattlesnakes are endangered in six states and threatened in five others due to habitat loss, unregulated collection, and indiscriminant killing.

I get being afraid of venom, what with the nausea, diarrhea, drop in blood pressure, and sensation that Hades himself is trying to bust through your skin. But of the 7,000 to 8,000 people struck by venomous snakes each year in the United States, only about 6 actually die from bites. (Side note: Please don’t call snakes poisonous. They’re venomous, and yes, there is a difference.)

And some vipers, like rattlesnakes, try not to waste their weapon on the likes of us, a trait I can’t help but admire. In fact, I’ll go as far saying rattlesnakes are rather considerate creatures. What other animal sits there and shakes a maraca until you go away? So the next time you hear that ancient rhythm coming from beneath a brush pile or rock outcrop, do us all a favor and get out of its way. Because who knows, the next tick it eats might be destined for you.

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image of Jason Bittel
OnEarth news blogger Jason Bittel contributes to Slate and serves up science for picky eaters on his website, Bittel Me This. He lives in Pittsburgh with his wife and two tiny wolves. (Note: wolves may be Pomeranians.) MORE STORIES ➔
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the rattlesnakes in my square mile neighborhood in town have killed my dog(agonizing pain) & others dogs & they DO NOT always rattle anymore. They are venomous & dangerous & they are excellently camouflaged with desert surroundings & way too easy to step on unawares especially for young children. If one never goes outdoors then don't worry but for the rest of us who do rattlesnakes are a very real fear. The anti-venom for my dog cost $1500.00 & my dog was destroyed & had to be put to sleep since the medicine did not help & his central nervous system was totally messed up. The non-venomous snakes can do the job of eating the rodents & we don't need the very real threat the rattlesnake brings to our families & pets. The rattlesnake should not in any way be glorified .
Bites are very often optional, and usually avoidable. It's unfortunate what happened to your dog, but you really believe that the response should be eradication of a group of wild animals? There is grace in understanding what happened, and none in revenge and useless actions. We build in their habitat, create perfect conditions for them, provide water, rodents, shelter ... then act surprised when wildlife is still there, acting as they would. All animals will act to prevent their own death, rattlesnakes included. Dogs are bitten when they try to attack rattlesnakes. Training, keeping a clean yard, and keeping pets on a leash all help, along with vaccination. The other option for the animal-loathing type: move to the city.
I've lived with the rattlesnakes for almost 30 years when I moved into their front yard and I am directly in their hunting path. Seems to be the magic number...but I relocate an average of 30 snakes per season (April through September) I try to find a mouse, vole or pocket gopher to feed them before taking them back up to higher ground, only to ensure their appetites are reasonably sated before coming back down the mountain to hunt....and possibly end up at my doorstep or in my raspberry patch (again) I try to practice and educate my guests of 'mindfulness'. Altho I actually levitated on one occassion...I've never been bit. On most occassions of rattlesnakes presenting themselves to me, it's me that frightens them the most. I've learned to respect their habitat and their ways. I've also learned that they don't allways give me an audible warning. My dogs have also learned to give them space over the years and because I watch and listen to my animals (cats, too) I have taught them to mind my commands to back off when a rattlesnake is warning. The best thing I can keep trying to do is to educate people; and to encourage them not to kill a creature simply because they fear it. The more you understand and learn about a creature...the less you will fear it...and the more you will appreciate and respect it.
The decline in rattlesnakes actually rattling can also likely be attributed to their persecution. Obviously, the snakes that rattle will be easier for a rattlesnake hunter to find and kill. Over time, those snakes that don't rattle as much have greater success surviving and reproducing and so the snake population gets quieter and quieter. I don't think you can blame the snakes for that either, just another example of how much we disrupt nature.
Woah, you're blaming the snake? If they killed your dog, how about responsible pet ownership? My cat almost got bit by a Massasuga, but guess what, I was right next to it and got my cat out of the snake's way. People who let their dogs roam around without watch is the problem, not the snake's. Every year, more people die from domesticated PIGS than any snake, and more die from CAT SCRATCHES. Snakes are demonized because of in the bible, it was said to be a serpent that deceived Eve. As the person who responded earlier said, bites are avoidable. Guess what? More snakes than Rattlers actually help people. King Cobras help with Strokes, their own bites, and even heart failure. Black Mambas and Pit vipers also help out with pain and neurological disorders. Snakes are helpful, I feel bad for your dog, but it's your own fault s/he died, not the snake's.