A Chihuahuan Hooknosed Snake we found in Cochise County, Arizona. These small snakes have a specialized scale on its face that it can use to help it uncover its prey: arachnids and centipedes. Of the snakes that can be found in Arizona, this is one of the least often seen, even by snake enthusiasts.
This one became defensive as it was being photographed, striking repeatedly at the camera with a closed mouth. This is a good example of why the popular saying “if it has a mouth, it can bite” is missing a critical component to be relevant: not just can it bite, but WILL it bite. This little snake says no.
A Chuckwalla surveys its vast domain, just north of the Grand Canyon. Here, these large herbivorous lizards take on a sandy, mottled color, making them harder to spot against the ground by predators flying overhead. For an observer at ground level, however, the shape of a vigilant lizards popping up from outcrops and boulders is much easier to spot.
Blacktailed Rattlesnakes can live in a wide variety of habitats, from high pine forests to low desert around sea level. This one was found in Greenlee County, Arizona several years ago.
An Arizona Black Rattlesnake comes out of its den for the day on a warm Spring day. This site is shared by three species of rattlesnakes, and at least a few species of other snakes. As spring egress progresses, each will use the area slightly differently, emerging, staging, and eventually distributing on their own schedules.
A Sonoran Whipsnake from near Phoenix, Arizona. These fast, diurnal animals can be seen on occasion darting across trails or roads, even in the peak heat of the day. Large, forward-facing eyes and a body style made for speed mean that any lizard that ends up in its sight isn’t going to have a good day.
They show up from time to time at homes at the very edges of the city. Based on our records of snake encounters at homes over the last 16 years, they are not as good at adapting to semi-developed areas as other, similar species, like coachwhips.
A few years ago, I saw what would be the only known record of one in the Piestewa Peak preserve area. It was in the middle of the night, resting in loose rocks in front of a spot where several Southwestern Speckled Rattlesnakes were about to give birth. Sonoran Whipsnakes include rattlesnakes in their diet, and I assumed it was waiting for that opportunity. Unfortunately, I chose to slowly reach for my camera rather than dive into to rocks to grab it, and it escaped without a photo record. So, an observation went into the notes for the night’s field session, but the preserve is still without an official record.
A Western Diamondback Rattlesnake communicating with me in the same way it does with any of the many predators that it fears. He stands up as tall as he can, hissing, rattling, and making the idea of coming any closer a decidedly bad idea.
What it isn’t doing: showing aggression. This behavior, even though it may seem scary (as it is intended to), is not a sign of “attack”, but a small animal’s best attempt at preserving its own life. For some reason, humans have a very hard time understanding this, and the incredibly simple way for everyone to leave safely: walk away. After a few photos, that’s what I did. Thanks for the heads up, snake.
An Arizona Ridgenosed Rattlesnake from the southeastern corner of Arizona. I photographed this young snake back in 2014 (that’s how behind I am in photos).
At this point, assuming she hasn’t met an end by fire, drought, bear, poacher, or any of the other ways a small snake can enter the carbon cycle, she is an older adult. She may have given birth every couple or few years, and still has a lot of life to live. Rattlesnakes can live for decades, continually learning to make better use of their environment and home range.
A Blacktailed Rattlesnake we found on a late night hike of a canyon near Phoenix, Arizona. These are common snakes in mountainous regions, often seen by hikers. During the summer in desert areas, they are often most often nocturnal, usually encountered around sunup and just after dark. This one, fortunately, lives far from where people may come across it on accident.
A Southwestern Speckled Rattlesnake resting along the top of a drainage after a night out. During the summer months, these and other rattlesnake species are primarily nocturnal, being encountered by people mostly in the hour before and after sunrise. As soon as the sun reaches the area, these snakes make a beeline for their aestivation sites to hide for the day.
The fact that rattlesnakes are often nocturnal and that they spend much of their lives avoiding excess heat is a surprise to many people. The misconception is that reptiles, ectotherms who get heat from the environment rather than produce it themselves, want it hot … the hotter the better. You’ll see this soon, in the form of comments like “it’s getting hot! It brings the rattlers out”, warnings from fire departments, and even articles in local news when temperatures stabilize in the triple digits for the year.
But thermoregulation means being the right temperature, not just as hot as possible. In fact, a body temperature sustained above around 105˚F can kill a rattlesnake. Interestingly, the upper terminal temperature seems to be similar across rattlesnake species, regardless of the environment they’re found. It’s often over 100˚F when these snakes begin their move back to their underground hiding spots, meaning they ride the line of death very closely, staying out as long as possible for the chance to find prey. If they are disturbed during this crawl for too long, or escape into the wrong hiding spot, it can quickly kill them.
We have learned this first-hand, unfortunately, from finding snakes within our study area who were first found by snake enthusiasts, likely mid-crawl. Thanks to Instagram, individual snakes that had died this way can be tied to individual events where a prolonged photo session and subsequent release of a heat-stressed snake resulted in death. To some herpers, it may seem like gatekeeping to discuss this kind of thing, but dead snakes are a lesson to those who would hear it.
During the summer, you may see us be critical of snake relocations performed by the fire department, and well-meaning individuals. This comes from the practice of releasing these snakes to improper cover, where they will be very unlikely to find survivable conditions in time. Every time you see a video of someone releasing a snake to open ground or random creosote mid-day, the relocator watches it crawl away and may be satisfied that they helped the animal … but these snakes do not survive for long.
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