A Guide to the Amphibians
and Reptiles of California
Living With Rattlesnakes
"Rattlesnakes are also among the most reasonable forms of dangerous wildlife: their first line of defense is to remain motionless; if you surprise them or cut off their retreat, they offer an audio warning; if you get too close, they head for cover. Venom is intended for prey so they're reluctant to bite, and 25 to 50 percent of all bites are dry - no venom is injected."Leslie Anthony. Snakebit: Confessions of a Herpetologist. Greystone Books, 2008.
Rattlesnake bites can be extremely dangerous, but rattlesnakes should not be considered as vicious and always ready to attack without provocation. They will not strike without a reason, but they will aggressively defend themselves. They are often portrayed with the body partly coiled, the tail rattling loudly, and the head up ready to strike. This display is a warning not to come any closer or they will strike; a defensive behavior that some rattlesnakes use when they sense that crawling away would put them in danger. If they are given some space and some time to escape to a safe place, they will usually crawl away as fast as possible.
Because they cannot crawl to safety as fast as some snakes, rattlesnakes often use their cryptic color and pattern to blend into their surroundings in order to hide from their prey and from other animals that could threaten them. They often hunt by sitting still and waiting for a warm-blooded prey animal to pass close enough for the snake to strike it. Sometimes a passing human will be struck instead, mistaken for food. When they sense the presence of something that might threaten them, rattlesnakes often lie still to avoid detection and do not rattle, because that would give away their location. At other times they rattle loudly, sometimes from a good distance, to warn potential enemies of their presence. In both cases they are doing everything they can to avoid confrontation and to avoid striking and biting and using up their valuable supply of venom which they need to kill and digest their food.
According to the Centers for Disease Control and Prevention, (accessed 4/23/2015) "It has been estimated that 7,000–8,000 people per year receive venomous bites in the United States, and about 5 of those people die."
A 1988 USC Medical Center study resulted in a profile of the average snakebite victim. It found that 44% of snakebites were accidental, more than half resulted from the victim handling a snake, 28% of the victims were intoxicated, and 90% of the victims were male, most of whom were in their 20s. This profile of the typical snakebite victim being an intoxicated young man who is handling a snake may not be entirely accurate, considering that it was only considered snakebite victims taken to one southern California hospital, and does not consider any other part of the country or any other snake other than rattlesnakes, but it has become the standard profile.
Most snakebites can
be avoided if you leave the snake alone - don't try to catch, kill, handle, or otherwise provoke a rattlesnake into acting in self-defense by striking. And always watch where you are walking and where you put your hands when you are in areas where rattlesnakes are present.
Handling Rattlesnakes - Don't Pin Them By the Neck!
Pinning rattlesnakes - holding them down with force at their necks - can be harmful to them and may traumatize them, which can be dangerous to you. There are better ways to handle them if you must, including using snake hooks, snake tongs (at midbody), snake bag sticks, and putting the head end of the snake in a clear plastic tube.
Herpetologist and author Harry Greene has this to say about pinning rattlesnakes:
"...while reviewing anti-predator mechanisms in reptiles, I learned that predators mainly attack their necks and heads. Heavy restraint, I concluded, by mimicking a terrifying natural encounter, might therefore be both psychologically and mechanically traumatic to a snake.
I had to acknowledge having pinned venomous snakes out of a misguided sense of necessity, but also because I liked picking them up, especially when others admired my skills: manhandling snakes entailed what naive bystanders regarded as charismatic prowess. Now, however, I had to admit snakes could be studied in the field, collected as specimens, and kept captive without our doing that to them…. For me the deal breakers were realizing that pinning is potentially traumatic and that the appearance of risk and bravery on the part of those doing it, as a matter for bragging, is misleading. Once I'd faced up to those truths I couldn't keep pinning snakes, let alone do it for the sake of showing off."
Harry W. Greene. Tracks and Shadows - Field Biology As Art. University of California Press, 2013.
Some people choose to have a rattlesnake removed from their property by an expert instead of trying to move it themselves. Often the snake they found is harmless, but they want it removed anyway. There are reptile relocators in many parts of the state where rattlesnakes are found that you can contact. There is a list available here: Melissa Kaplan's List of Reptile Relocators in California.
Is the venom in western rattlesnakes evolving and becoming more dangerous to humans?
Are Rattlesnakes Rattling Less and Losing Their Rattles?
There has been a lot of discussion online about rattlesnakes that have evolved to remain silent instead of using their rattle as a warning. This is usually accompanied by hysterical comments about how horrible it will be to live in a world where rattlesnakes no longer warn us where they are located so we won't step on them and get bitten. Some commenters are going so far to say that rattlesnakes are actually losing their rattles or their ability to rattle. I have seen no evidence to support the fact that rattlesnakes are losing their rattles, but this 2013 NPR News article contains an interview with a herpetologist in South Dakota who claims to have found many rattlesnakes whose tail muscles have atrophied to the point where they can no longer shake their tails to make a rattling sound. I don't know if a study has been published about this phenomenon yet, but regardless of the expert source, without a detailed study this is just more hearsay that cannot be taken too seriously.
There are good arguments from snake experts on both sides of the issue:
Some claim that rattlesnakes that remain silent to remain undetected are less likely to be discovered and killed by humans, and that this trait is passed on to succeeding generations. That could be true. It's how evolution works. But I doubt that evolution works as fast as they claim.
Others believe that rattlesnakes have never rattled a warning all of the time or even most of the time, so really nothing has changed and there is no reason to believe that snakes that don't rattle are a new development. I'm inclined to agree with this view because it is consistent with my experience. I've seen rattlesnakes in areas where they could not have had much contact with humans that did not rattle when I encountered them and I've seen others in the same areas that did rattle.
The one thing that experts on both sides of the issue agree on is that it is always important to be careful and alert and rely on all of your senses, not just your ears, to detect rattlesnakes when you are in their territory.
Don't expect a rattlesnake to always rattle a warning.
Here are a couple more links regarding this topic. Google can show you even more.
There are several types of snake repellents on the market. Some plug into the ground, claiming to make vibrations that snakes will avoid. Some are powders or liquids that you pour onto the ground, with names such as Dr. T's Snake-A-Way, SerpentGuard, Sweeney's Snake Repellent, Hi-Yield Snake Repellent, Snake Stopper, and Liquid Fence. These typically guarantee to get rid of venomous and non-venomous snakes and keep them from coming back. They claim to be eco-friendly, and use ingredients such as cinnamon, cloves, and fuller's earth, or sulphur and naphthalene (moth balls.) I can't recommend any of them because I have not tested them nor heard from anyone who has had success with them. It would be hard to determine if it works anyway, since snakes are secretive and often nocturnal, so you have no way of knowing that it is working unless you see snakes, which means it isn't. There are YouTube videos claiming to prove that repellents work and others showing that they don't work, such as this one, which makes a very good case against one particular brand, showing that 3 venomous species and one non-venomous snake that were placed inside a wide band of repellent applied in a large circle on the ground, did not hesitate to crawl through the repellent.
There are also snake traps on the market, such as Snake Guard Snake Trap and Cahaba Sake Trap. These are similar to "roach motels," being open-ended flat boxes with a sticky bottom. When the snakes crawl into the box, because it looks like shelter, they will get stuck. You can then kill the snake, if you find it before it hasn't died from starvation, exposure, or from being eaten by scavengers, or you can release it after spraying it with non-stick cooking oil. I have not tested these traps, but I suspect they do work, as long as a snake crawls into the trap. That's the problem, since there is nothing inside to attract the snake. It can also be an inhumane method of capture unless you check the trap daily, and will also trap and kill any other kind of animal or invertebrate that enters the box.
I've seen Snake Fences for sale, which consist of synthetic netting on small posts about a foot high that you stake to the ground. If a snake tries to crawl through the net, it will get caught. This will probably also work, if you use enough of it, but it is a terribly inhumane method which leaves a snake to suffer, die, and rot or get eaten by a scavenger. You can see more about this subject on my Living With Wild Reptiles and Amphibians page.
Some dog owners pay to have their dogs trained to avoid rattlesnakes. Some people think this is cruel to the dogs because it uses electrical shock collars to shock the dog when it gets near a snake, and even cruel to the snakes. The training does not always appear to be effective on all dogs.
Organizations like the Humane Society offer the training for a price. Natural Solutions is an online company that also sells this training service (in Southern California, at least.)
I can't recommend any of these training programs since I have no personal experience with them, but I have heard from dog owners whose dogs were trained but failed to avoid rattlesnakes, and from others who say the training works. More than one training may be necessary. I have heard animal experts recommend that once the training is completed, dog owners should not automatically assume that their dog will always avoid snakes, but should watch the dog carefully to make sure the training worked. One person whose dog seemed to fail its first training had his dog trained a second time by Natural Solutions with more positive results.
Rattlesnake Vaccines For Dogs
There are a number of companies that offer vaccinations for dogs in order to protect them from rattlesnake venom. I have not researched the validity of their claims so I can't endorse them or tell you to avoid them. You will need to figure that out on your own. I have chosen one site Rattlesnakevaccinations.com to illustrate the claims about what these vaccines will do. Keep in mind that while it looks like unbiased scientific information this site is basically just an advertisement for a particular product. (A product which may work very well, I don't know for sure.) They state that "Rattlesnake vaccine is designed to reduce the likelihood of death, permanent injury, and severe pain caused by rattlesnake bites. The vaccine stimulates the dog's immune system to produce antibodies against rattlesnake venom." They also state that the vaccine doesn't contain the sheep or horse proteins found in antivenom which can cause severe allergic reactions. One vaccine is given, then another is given 30 days later, and then a booster is given every 6 months to a year.
Another company that offers information about vaccines is Rattlesnake Vaccines for Dogs.
If you live near the San Jacinto Mountains in Southern California, the Idyllwild Antivenom Group offers antivenom for pets who have been bitten by the Southern Pacific Rattlesnake and information about pets and rattlesnakes.
Some opponents feel that they promote animal abuse and slaughter for amusement and that they use collecting practices that destroy natural habitat.
Some supporters believe that a Rattlesnake Roundup is a part of their cultural tradition and is beneficial because it brings money into the community, it educates people about rattlesnakes, and it provides venom for the manufacture of antivenom.
Here are some Rattlesnake Roundup opponents' views:
Drawings showing how to identify the different species of US rattlesnakes and other venomous snakes.
Recognizing the Differences Between Rattlesnakes and Gopher Snakes
A harmless gopher snake is sometimes mistaken for a venomous rattlesnake and killed unnecessarily (by someone who wrongly believes that all rattlesnakes should sy to avoid this mistake and save the life of a harmless beneficial snake by learning to tell the difference between a gopher snakbe killed.) It is eae and a rattlesnake.These signs explain how to do that. Still, if you do not have training in handling venomous snakes, you should never handle any snake unless you are absolutely certain that it is not dangerous.
Books about Rattlesnakes
Ernst, Carl. H. Venomous Reptiles of North America. Smithsonian Institution Press, 1999.
Hayes, William K., Kent R. Beaman, Michael D. Cardwell, and Sean P. Bush, editors. The Biology of Rattlesnakes. Loma Linda University Press, 2009.
Hubbs, Brian R., & Brendan O'Connor. A Guide to the Rattlesnakes and other Venomous Serpents of the United States. Tricolor Books, 2011.
Klauber, Laurence M. Rattlesnakes. University of California Press. (Abridged from the 1956 two volume Rattlesnakes:
Their Habits, Life Histories, and Influence on Mankind.) University of California Press, 1982.
Rubio, Manny. Rattlesnake - Portrait of a Predator. Smithsonian Institution Press, 1998.
Walls, Jerry G. Rattlesnakes: Their Natural History and Care. T. F. H. Publications, Inc., 1996.
Klauber, Laurence M.
University of California Press. (Abridged from the 1956 two volume Rattlesnakes: Their Habits, Life Histories, and Influence on Mankind.) University of California Press, 1982.
Klauber, Laurence M.
Rattlesnakes: Their Habits, Life Histories, and Influence on Mankind.
University of California Press, 1956. (Hardcover 2 volume set.) (Second Edition, 1997.)
Hubbs, Brian R., & Brendan O'Connor. A Guide to the Rattlesnakes and other Venomous Serpents of the United States.
Tricolor Books, 2011.
The classic guide to rattlesnakes by the great California Herpetologist.
The original 2009 guide to the rattlesnakes of the United States has been expanded to cover all of the venomous serpents of the United States, including Rattlesnakes, Coral Snakes, Copperheads, and Cottonmouths, with 170 color pictures and 42 range maps.
Rattlesnake - Portrait of a Predator.
Smithsonian Institution Press, 1998.
Hayes, William K., Kent R. Beaman, Michael D. Cardwell, and Sean P. Bush, editors.
The Biology of Rattlesnakes.
Loma Linda University Press, 2009.
Ernst, Carl H. and Evelyn M. Ernst. Venomous Reptiles of the United States, Canada, and Northern Mexico: Crotalus (Volume 2)
Johns Hopkins University Press. 2011
Lots of good pictures and information about buzzworms in this nicely-designed book.
"Due in part to the toxic nature of their venom, rattlesnakes comprise the most popular and well-studied group of snakes in the world. The Biology of Rattlesnakes showcases the finest research to date by investigators encompassing an enormous breadth of expertise. With 50 original contributions from 98 authorities covering a diverse range of topics, this landmark volume will be looked upon as authoritative for years to come. The beautiful, full-color plates depicting many of the more than 30 rattlesnake species add a tasteful touch."
This is an updated version of the landmark reference Venomous Reptiles of North America which has been split into two volumes and now covers northern Mexico. Volume two covers all of the crotalus species in North America north of Mexico's twenty-fifth parallel.