Among our most universal and compelling fears, one that is widespread across cultures, continents, and through vast spans of time, is the fear of snakes. In terms of simple survival, this makes perfect sense; many snakes can be lethal. For countless millennia, I am sure that people knew which snakes were dangerous and which were not.
In modern times, our culture has become so disassociated with the natural world that most of us can no longer identify what species are harmless and what kinds are not. The deep-rooted, possibly instinctual fear of snakes remains – when coupled with widespread ignorance, it results in the needless death of many snakes every year. You say rattlesnakes are easy to identify? Tell that to the many people who have killed slightly similar gophersnakes, thinking they were rattlers. Or to the screamers that wield shovels in attempts to automatically kill any snake they see.
The photograph above the title depicts a pair of mating western diamondbacks. A reminder – if you are viewing this in your email, you will not see the header images. Move your cursor over the title and click on it to be re-directed to my blog site, where the header images appear and where other images are larger as well.
What follows is a celebration of the beauty, grace, and elegance of the remarkable animals that we call snakes. Thirty-four species inhabit the Middle San Pedro Valley. Here is a sampling of a few that I have had the delight to encounter…
A Sonoran coralsnake, (Micruroides euryxanthus), a highly fossorial, nocturnal, (and therefore seldom-seen) species. The striking aposematic coloration of these beautiful reptiles is a clear warning to many would-be predators. Bites from these small snakes are very rare – and very serious. The venom is primarily neurotoxic; drop-for-drop, it outdoes any other southwestern snake for sheer potency.Sonoran coralsnakes are small, (rarely over two feet in length) shy, and retiring, preferring to hide their heads when threatened rather than strike defensively.
Gophersnakes, (Pituophis cantenifer), are Arizona’s longest serpent, capable of reaching lengths of over eight feet. These powerful constrictors are experts at preying on rodents. A special scale armors the front of their snout, enabling them to push through soil in rodent tunnels with ease. Gophersnakes play a key role in landscape-scale ecology by controlling rodent populations. This also makes them an ally to ranchers and farmers.
Sadly, many are killed by ignorant people who mistake them for rattlesnakes, and many more are intentionally killed by drivers, brutal acts that are a mark of cruel, simple-minded people.
While gophersnakes are common in Arizona, this one is very rare due to the aberrant patterning on the upper parts of its body. The usual dorsal blotches have been replaced by long, striped markings. Glossy snakes, (Arizona elegans), are quite common in the Middle San Pedro Valley. This species can attain lengths approaching six feet. At a glance, it is not hard to confuse these snakes with gophersnakes.
A Sonoran lyresnake, (Trimorphodon lambda), curled up against the wall of my adobe residence. Lyresnakes are fascinating; their large eyes feature vertically elliptical pupils, whereas most of our other snakes have round pupils. This is a nocturnally active species whose its diet is composed primarily of lizards. Lyresnakes don’t have injectable venom; instead, they secrete venom from glands in the rear of their mouths that is very toxic to lizards – but not to humans.
A typical “pink” coachwhip, (Masticophis flagellum). Coachwhips are often erroneously called “racers” or “red racers” by local residents. Coahwhips are phenomenal creatures, the true “über predators” of the southwest. Equipped with large eyes capable of exceptional long-distance acuity, coachwhips are the desert’s fastest snakes, and are surely among the fastest in the world. These are extremely alert reptiles that specialize on hunting lizards but will also consume a wide variety of other prey items. Coachwhips occur here in three color phases, with intergrades as well. The pink phase predominates locally.
I spotted this long-nosed snake, (Rhinocheilus lecontei), crawling across the dirt floor of our open shed on a warm, early summer morning. Its vivid colors and patterning are a reminder that snakes can be very beautiful creatures.
Long-nosed snakes occur in southern Arizona in two main color morphs. This is the other one, a completely different mix of colors and patterns compared to the individual above.
A California kingsnake, (Lampropeltis californiae). To me, this is one of the most beautiful snakes in Arizona, combining a chain-like pattern of cream-yellow bands set against a glossy, satin-black background. Kingsnakes are snake specialists, actively hunting many other species including rattlesnakes – kingsnakes are immune to their venoms. In addition to snakes, other foods include small rodents, eggs, and lizards.
A desert kingsnake, (Lampropeltis splendida) This species occurs locally in two primary color phases – the one pictured here is the most common. Some desert kingsnakes exhibit melanistic (all black pigmentation) coloration.Checkered gartersnakes, (Thamnophis marcianus) prefer habitats near water sources such as streams and ponds, where one of their favorite types of prey can be found most reliably – amphibians. Three species of garter snakes inhabit the San Pedro River Basin.
Rattlesnakes are the victims of more prejudice and brutal cruelty from people than all other American snakes – most often, the prejudice and cruelty arise from deep ignorance. We tend to overlook the comforting fact that rattlesnakes are among the very few toxic snakes on Earth that give us the courtesy of a warning. This western diamond-backed rattlesnake, (Crotalus atrox), is one of several that I see quite often around our buildings. Bites from this potent species are very serious, but also very rare IF one simply pays constant, close attention to where one’s feet and hands are placed when outdoors. We never kill these snakes, (nor any others, for that matter). Most diamondbacks are shy and inoffensive if left alone. Quite abundant in many habitat types, diamondbacks play a very important role in local ecology by helping to control rodent populations.
Of the world’s 36 species of known rattlesnakes, surely the black-tailed rattlesnake, (Crotalus molossus), would win one of the top prizes for sheer beauty. My wife and I spent half and hour watching and photographing this unagressive, beguiling individual. We found it basking, suspended several feet off the ground among tree branches in a walnut – velvet mesquite bosque. This one was large for its kind, close to 48 inches in length.
I had to radically adjust my search image for local rattlesnakes when I uncovered this snake in our shed, an Arizona black rattlesnake, (Crotalus cerberus), curled up beneath an inverted wheelbarrow. Before that moment, my search image had concerned itself only with the grays and dull browns of western diamondbacks; black rattlesnakes were not “known” to inhabit low-elevation places like our valley-floor bosque, situated at 3,100 feet. Since then, I have recorded this species locally several more times.
The Mohave rattlesnake, (Crotalus scutulatus), is the most potent rattlesnake in the entire American west, injecting substantial amounts of strong neurotoxic venom when it bites. This one emerged from under a stack of lumber that I had been working with, furnishing an unforgettable reminder that only fools slip their hands under wood stacked outdoors without looking carefully beforehand.
The most reliable way to visually identify Mohave rattlesnakes is to get a close look at their supraocular scales that lie atop the head between the snake’s eyes. It is difficult to do this safely without a good pair of binoculars with close-focusing ability. Diamondbacks can look quite similar to Mojave rattlesnakes, but their supraocular scales are much smaller and more numerous. Adding to identification difficulties, the two species have been known to hybridize in Cochise County.
Small and inoffensive, ring-necked snakes, (Diadophis punctatus) are common in the San Pedro River Drainage.
When threatened by a predator, ring-necked snakes may flip themselves upside-down, feigning death while revealing their striking, aposematically-colored ventral side.
Eastern patch-nosed snakes, (Salvadora grahamiae) feel like smooth satin when handled. This species is always among the earliest to emerge when the weather begins to warm in the valley, often above ground by mid-March. Note the heavy scale at the proximal end of the snake’s head, armoring for its snout as it digs underground in loose soils.
Upon lifting a pile of old branches and debris one day, I exposed this incredibly tiny snake, a highly fossorial species I had never seen before.
My first thought was, “I never knew earthworms lived on our bosque,” until I looked closer and picked it up. Coiled in my palm with room to spare was this amazing western threadsnake, (Rena humilis). Threadsnakes prey on ants, ant eggs, ant larvae, and termites. They are a favorite prey item for Sonoran coralsnakes.
Replace ignorance with knowledge. Be kind to snakes.
I have seen more rattlesnakes around our home this summer than ever before. During the past six weeks, not a single day has passed when I have not seen at least one western diamondback here – on several days, I have seen as many as four. I don’t mind their presence. This would be a very dull world if it were danger – free, cleansed of any creatures that might harm us. The snakes have a right to be here – this land is not just habitat for me and my family, but habitat that we share with many other living things.
Yesterday morning brought a surprise that lay snoozing a few feet from my doorway. It was yet another rattlesnake, but the instant I saw this one, I knew it was not a western diamondback, but a Mojave rattlesnake.
Most of the time, when I spot a poisonous serpent close to our home, I simply leave it alone. Given this snake’s proximity to an area that gets frequent daily foot travel, and the extreme toxicity of its venom, I decided to relocate it. I picked the rattlesnake up with a pair of snake tongs, lowered it into an empty trash can, and hauled it to a new home downriver. During the entire procedure, the snake shook its tail only once, and briefly at that.
I knew immediately when I saw this snake under the ramada that it was a Mojave. The greenish-yellowish tinge to its skin stands out in contrast to the local western diamondbacks, whose coloration tends to be more silvery gray. Note also the sawtoothed edging to the snake’s dorsal blotches. Our diamondbacks rarely show such edges on their “diamonds,” or dorsal blotches.
How toxic is this snake’s venom? Some sources say the venom of Mojave rattlesnakes is ten times more potent than that of other rattlesnakes. (There is one notable exception here – tiger rattlesnakes, which also occur in the Middle San Pedro Valley, are nearly as potent as Mojaves.) Other sources label this species as one of the most toxic snakes in the entire hemisphere. That is saying a lot, especially considering some of the elapid snakes that live in Central and South America. As if that were not enough, research has demonstrated that the Mojave rattlesnakes that inhabit Cochise County produce a unique venom that is even more potent than that of other Mojave rattlesnakes in other parts of their range. Rattlesnake venoms are complex organic cocktails consisting of many ingredients including proteins, polypeptides, metal ions, fats, enzymes, and more. Most rattlesnake species have hemotoxic venoms – venoms that destroy red blood cells, interfere with clotting, and damage tissue. The principal components of Mojave venom are neurotoxic – they act on the central nervous system. A bite from one of these snakes can cause severe paralysis and even cardiac arrest.
So yes, I decided to move the snake away from our home.
This Mojave rattlesnake was captured and relocated by a warm-hearted friend a few years ago; he brought the snake to here to show it to me before releasing it back into the wild. This snake was on his doorstep as well, better relocated than shot or clubbed to death.
Much like sharks or grizzly bears, rattlesnakes are widely misunderstood and unjustly feared by the public. These fears are rooted in ignorance and a cultural bias regarding the world of nature and our place in it. Here in Arizona, where rattlesnakes are common and widespread, more than half of all bites are provoked. (Yes, Darwin was right!) Most of the remaining bites could be easily avoided by a combination of unflagging awareness, protective footwear, and snake gaiters. Awareness means keeping one’s eyes fixed carefully on the ground when moving around outdoors, and always using flashlights after dark. If you look carefully where you are going, you are much less likely to step too close to a snake. When I hike locally during the warm months, I always wear a pair of leather boots and snake gaiters. Simple precautions can really pay off.
Identification of Mojave rattlesnakes is not always a simple task; occasionally, these snakes hybridize with western diamondbacks. They also come in many differing shades of color. The most certain identifying characteristic are the two large scales atop the snake’s head that lie in-between its supraocular scales – (the very large scales that cover
the upper portion of the snake’s eyes). Western diamondbacks usually have six or seven much smaller scales between their supraoculars.
If a person does get bitten, it is imperative to get medical help as soon as possible. Time is utterly crucial when it comes to treating snakebite victims. In this rural landscape, that means a helicopter flight to a hospital in Tucson. The average cost of treating a bite victim has risen to over $75,000 per incident. With that in mind, I think that a small investment in a pair of snake gaiters (most cost less than $100 per pair) and some good boots is a very wise move.
Tail markings are also useful in identification. Mojave rattlesnakes usually show narrower, less distinct black banding on their tails than diamondback rattlesnakes.In contrast, most western diamondbacks have considerably wider, distinct black bands on their tails.
In closing this post, I must say that I do not recommend relocating reptiles. For rattlesnakes, relocation beats getting killed, but is stressful to them, and can result in an inability to survive. Rattlesnakes occupy definitive home ranges, areas that they come to know and navigate through successfully. One of the most critical aspects of their lives has to do with knowing where a suitable site is for hibernation. (The correct term in use these days is “brumation,” not “hibernation.” I used the old term because many more people are familiar with it.) If a snake cannot find its way to such a site, it is not likely to survive the winter. Relocated snakes have been documented to have problems with this, especially if they are moved late in autumn.
