A couple of Arizona Black Rattlesnakes tucked away in a den in central Arizona.

A couple of Arizona Black Rattlesnakes tucked away in a den in central Arizona.

We saw this Western Diamondback Rattlesnake resting high on a ledge, just below a crevice where at least one other was resting.

A young Arizona Black Rattlesnake resting outside its den, where several larger adults have yet to emerge for the day. In time, it will darken and its pattern will fade to be the familiar dark black with yellow bands common in the region.
This same little snake, a year prior and a lot smaller, was what first gave this spot away as a rattlesnake den. Females stay at or near winter dens all year to give birth there, so a chance sighting of a neonate in August was an indication there was more to be found. Since then, I have found dozens more Arizona Black Rattlesnakes, as well as Western Diamondback Rattlesnakes and Blacktailed Rattlesnakes sharing the same den.

A large male Western Diamondback Rattlesnake cruising through dense vegetation, on the lookout for others that may be near. At this higher elevation den in the late fall, the females are already tucked into rock crevices and caves. All that remain on the surface are the largest males, patrolling for rivals, and getting into the occasional fight. This one finished its loop and settled back into the sunny spot it prefers for awhile, before doing it all again about an hour later. Why wait until spring to fight for the good spot, when you can do it in the fall?

This Arizona Black Rattlesnake noticed me at the same time that I saw it as I climbed up a steep, rocky hillside. I stopped and got a few photos, and saw another one right next to it deeper in the crevice of the rocks. I was able to then back down the hill for another route up without further disturbance, and it resumed its move out to the open to get some sun.

Three of the half dozen or so Western Diamondback Rattlesnakes that occupy this den each winter. These snakes spend a lot of time during the early spring basking and making short movements to thermoregulate and for social reasons, where they are vulnerable to predators and other threats.

A Gila Monster peeking out of its spring staging spot, just down the hill from where it spent the winter. It shares this spot with several other Gila Monsters, a handful of Western Diamondback Rattlesnakes, and the occasional tortoise. It will spend the majority of each day during the early spring doing, basically, this. Resting in partial sun, disappearing if predators approach, and waiting to head out in nest-hunting mode as soon as the time is right.

A Gila Monster out and about on a spring day a couple of years ago. On mild days, these animals start to move away from often communal dens to springtime staging areas. They may take daily patrols, searching for nesting mammals and quail eggs. It’s common for hikers to report them on social media frequently within a few days’ time, usually in late February or early March, which is a reliable signal that the process has begun each year.

After a relatively unproductive weekend in the early Spring at higher elevation, I made a quick stop by a large rocky outcrop on the way home on a whim. I have been driving past this particular rock for more than a decade, always in a hurry somewhere or dead tired, always thinking “one nof these days, I’ll check that out; it has to be a den“. Well that day was the day, and of course, it was a winter den. This large blacktailed rattlesnake was laid out over a boulder getting some sun, with others another in the crevices behind it. I’ll check it out again next year in more prime conditions.

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.
