Month: August 2021

The World’s Most Potent Rattlesnake at my Doorstep

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.

A Gila Monster Rescued, Mating Rattlesnakes, and Images of Life Sparked by the Monsoon Rains

Arizona’s spectacular monsoon season is in full swing this year. Here in the Middle San Pedro River Valley, we have received 7.28 inches of life-giving rain during the past seven weeks. Life of all kinds is emerging, much of it empowered by this season alone.

The strikingly beautiful Gila monster pictured above was photographed by my wife Kathleen just days ago. (One more reminder to my readers: if you don’t see that image, it is because you are viewing this in your email. Always go to my blog site – https://ralphwaldt.com – to see this post as I intended it, without omissions.) It is one of many desert animals whose activity increases or otherwise changes as a result of monsoon weather.

The world we live in has been under deep duress this past year; the global pandemic, political division, economic hardship, and numerous worldwide catastrophes have all combined to make many people feel stressed and depressed. That is the anthropocentric world. A wider view – beyond the human-centric world that we pay so much attention to – encompasses the rest of the planet’s glorious and infinitely varied life. When I feel overloaded after viewing the day’s headlines, I can always find a source of solace, reassurance, and joy simply by abandoning the vicarious, shallow world of my computer screen in favor of the outdoor world. All it takes is a few steps outside. Sunlight, vivid green plants, lizards, trees, bird song, fresh air… the real world is medicine for the soul.

One does not need to live in a rural area like I do in order to tap into the natural world. I have a friend who lives in suburbia, along the fringes of the immensity known as Dallas-Fort Worth. He spends time in his backyard where trees, shrubs, and a garden bring life and happiness into his world. There are no bears, cougars, or Gila monsters in his yard like there are here – but there is a diverse variety of life. My friend focuses his attention on smaller creatures and other forms of life; insects, lizards, and flowering plants, for example. He photographs what he sees – things that most people never even notice. The photographs from his back yard are often stunning, revealing a world remarkably rich in life captured by a talented, artistic photographer whose sharp observational skills remind us that life is everywhere, and that life is beyond beautiful.

With those thoughts in mind, I offer a series of recent images taken during the heart of the monsoon season here in the Middle San Pedro Valley of southeastern Arizona…

My wife, Kathleen, encountered this Gila monster as it was attempting to cross a public roadway. She did the right thing – she pulled off the side of the road, turned on her hazard lights, and stood by, ready to usher the lizard out of harm’s way should a speeding motorist arrive on the scene. As the Gila monster made it safely off of the pavement, it turned to face Kathleen and her camera, then ambled off into the desert. The lizard was lucky this time. Large numbers of reptiles are killed on Arizona’s roads every day, many of them by people who are fast drivers and/or simply harbor callous attitudes towards reptiles. All it takes to avoid such losses is slower speed and a modicum of care for the life we share the planet with.

A single feather laying in front of our ramada had a story to tell: a great horned owl had landed there the night prior, likely as it pounced on a prey item.

Mornings that follow monsoon rain storms often reveal the nocturnal work of encruster termites. These tiny insects encrust plant stems (or in this case, mesquite beans) with a mixture of soil particles and viscous saliva, then feed on the encapsulated items. Termites are exceptionally important components of this ecosystem; they are very numerous, widespread, and perform a crucial ecological function by breaking down plant cellulose, thus returning essential nutrients to the soil.

Some two decades ago, I first tasted wolfberries – they were delicious. Native peoples gathered these berries as a seasonal food source. A large number of birds and mammals utilize them as a high-calorie-per-unit-weight food source, packed with natural sugars. This plant is of the genus Lycium.

Summer raindrops adorn the fresh blossom of an Arizona poppy plant, Kallstroemia grandiflora.

One of the valley’s most common summer wildflowers is also among its most beautiful; trailing four o’clock, Allionia incarnata.

The emergent blooms of a barrel cactus. These cacti rely on summer rains for their annual reproductive efforts.

Silver-leaf nightshade – Solanum elaeagnifolium – always a joy to encounter, this native plant is grouped in the same botanical family as tomatoes, but it is not safe for human consumption.

Tarantulas are common here, but can be seen with any frequency only during the monsoon season, when lower daytime temperatures and increased humidity bring them out of hiding. If left alone, these are harmless, innocuous creatures.

Caterpillars of the white-lined sphinx moth (and other native Sphingicampid moths) are very common sights during summers graced by monsoonal moisture. When mature, they reach a size approximating that of a person’s index finger.

A few days prior, I encountered this mating pair of diamondback rattlesnakes just outside my shop door. Courtship and mating in this species is a process that can go on for several days.

Another diamondback appeared here last week, a large individual. This snake is quite rotund in the latter half of its body – I’d guess that it was a gravid female. Snakes are a valuable asset here, for they are a major help in controlling rodent populations. Mice and rats in southern Arizona could win gold medals for their ability to get into vehicle engines, where they cause frequent and very expensive problems.

Puffballs sprout from the floor of our mesquite bosque with great speed after summer rainfalls. Puffballs are specifically designed to work with rain. First, an initial rain is required to soak the soil. This enables the spherical mushrooms to sprout above the surface. Puffballs quickly mature, then wait for the next rainfall to facilitate their reproduction. When raindrops impact a puffball, they cause a sudden increase in internal pressure, forcing thousands of minuscule spores to erupt (or “puff” like smoke) out of the hole in the top of the mushroom. By releasing its spores only in response to falling rain, the fungus assures that freshly moistened soil is available the enhanced survival and successful growth of its offspring. Pretty cool or what?

An Incredible Explosion of Life

July brought us over six inches of very welcome rain! The summer monsoon – one of five distinct seasons here – has returned to southern Arizona after a two-year near-absence. Purple martins are cruising above the treetops and a family of Mississippi kites has been visiting us for days. We are seeing rattlesnakes on a daily basis. On sultry, warm nights, elf owls have been calling in the wee hours of the morning. Saguaros are fattening as they transport water in their tissues. Native grasses are  sprouting. The land and its life are rejoicing.

The changes on the landscape are incredible, happening with amazing rapidity and soaring fecundity. The mesquite bosque surrounding our home had been without a green understory during the entire past two years. Not any more! One glance out the window reveals a near-jungle of dense greenery standing five feet tall – much of it composed of one dominant plant with the unflattering common name of “pigweed.”

Fresh growth emerges with stunning speed and vigor after nitrogen-rich summer rains soak the land. This image is a week old; the understory plant community has doubled in height since then.

Pigweed is known to botanists as Amaranthus palmeri, and it is certainly not a “weed.” In the conventional sense, most of us consider weeds to be troublesome non-native plants. This one is a native species, and its presence speaks of great benefits to the land and its wildlife.

One of the primary winter forage plants for the deer that inhabit this river valley is pigweed. A good source of winter forage is critically important to wild ungulates. Rabbits, hares, javelina, and many rodents feed on the green plants in summer. Once the seed heads form, they tend to remain through autumn and winter on dead, standing plants. Great numbers of various species of sparrows winter in southern Arizona. The  seeds of pigweed are heavily fed upon by many of these sparrows and other native birds as well. Something that is very obvious, but often overlooked by many people, is the fact that the dense stands of pigweed are shading the ground. I can’t stress enough how important shade is in desert ecosystems! The ground retains much more moisture and soil temperatures are far lower, allowing fungal hyphae and numerous other microflora and microfauna to work in shallower horizons of the soil. This benefits all life.

The summer rains bring many creatures out of hiding. Among these are toads, countless insects, red velvet mites, and the largest millipedes living in the United States…

Giant millipedes spend nearly all of their lives underground, typically emerging only after monsoon rainstorms. This one was about five inches in length; some sources claim this species can reach up to nine inches in length. These fascinating, innocuous arthropods can live for ten years, growing longer as they add more body segments every time they shed.

I had taken several shots of the millipede, working close to the ground, before I noticed this small diamondback curled sixteen inches away. It never made a sound. When left undisturbed, these snakes are rarely aggressive. Their primary method of defense is stillness and excellent camouflage.

When one of these huge beetles comes flying by, it is guaranteed to get your attention. This is a palo verde root borer, measuring in at three inches in length. These beetles are another example of the many species that are brought out from hiding by the rains.

For many of our of native amphibians, monsoon rains furnish their only chance to reproduce successfully.  A strong population of spadefoot toads inhabits this valley, but they remain completely sequestered until strong summer rainstorms bring them up from their deep underground burrows. On July 3rd, the first monsoon storms rolled in –  a succession of two storms with plenty of lightning and life-giving rainfall. That night, the landscape was ringing with the voices of hundreds upon hundreds of spadefoot toads.

Couch’s spadefoot toad is the most abundant amphibian in the Middle San Pedro Valley, but only summer residents witness them.

A pair of Couch’s spadefoots mating. These amphibians must lay their eggs in water. In desert environments, the toads wait for summer storms to create suitable pools of water. Here, the male is grasping the female in a posture known as amplexus – when she lays her masses of eggs, he releases sperm into the water.

Spadefoot tadpoles mature more quickly than almost any other tadpoles on the planet – in as little as nine days. This is a species that has evolved to live in a hot, dry desert environment, where pools of water are not only rare, but tend to be very short-lived. It pays to mature quickly under such demanding conditions.

It is hard to say what to call the amphibians in this brief period of their lives; tadpoles or toadlets? At this stage in their development, the tails shorten very quickly. As newly formed toads appear, they can be seen hopping by the dozens out of their natal pond.

Just two days ago, despite the fact that I am always on the lookout for rattlesnakes, I nearly stepped on this one that was well camouflaged under the ramada. I am glad that we did not have an unfortunate interaction.