An Arizona Black Rattlesnake from relatively open desert in Maricopa County, Arizona. This species is diverse in appearance and habitat preferences, with this particular population inhabiting generally lower, hotter, and exposed areas.
cerastesA Sonoran Sidewinder that had just crossed a road west of Phoenix. These small specialist rattlesnakes are abundant in the right conditions. This is the reason that hikers will almost never come across one … the flat sandy habitat they need is nobody’s hiking destination.
Leavitt, D. J., & Grimsley, A. A. (2019). Density, recapture probability, biomass, productivity, and population structure of Sidewinders (Crotalus cerastes) in the Sonoran Desert of Arizona. Herpetology Notes, 12, 427–435. https://www.researchgate.net/publication/332802062
A Gila Monster out and about on a warm Spring day that I found a while back.
At that time, more than a decade ago, I knew relatively little about the day-to-day habits of these animals. Finding one was more a matter of luck than anything else. But, I’ve since learned a lot, and these are now often a higher observation count in a day than I’d had seen in an entire year.
Recommended reading, if you can find it:
Biology of Gila Monsters and Beaded Lizards — Daniel D. Beck (UC Press)
A young Sonoran Whipsnake near Phoenix. These snakes are extremely fast, daytime hunters that go after everything from lizards to other snakes. Most encounters people will have with them are as a blue-grey blur disappearing into the bushes, where it will seem to just teleport to another dimension if you try and find it.
Despite being incredibly easy to observe in surrounding mountain ranges, the Southwestern Speckled Rattlesnakes in the Sierra Estrella just southwest of Phoenix are harder to spot. They’re likely just as common, but the steep terrain and majority of prime geology for the species being inaccessible reservation land make it a challenge to see one. Kris Haas spotted this pretty one way up mountain.
A Mojave Rattlesnake from the Phoenix area. These snakes are common in the flatter, creosote and grassland areas of the state. This one obeys the all the ID rules, with much wider white tail bands than black, yellow proximal rattle segment, and a post-ocular stripe that extends back to never intersect with the mouth.
A Blacktailed Rattlesnake hiding deep in a cave on an extremely hot day. During the heat of summer, rattlesnakes like this one may stay hidden away from lethal temperatures, staying in one spot or coming just outside the entrance after dark.
Coachwhips are out and about on even the hottest days, rarely active at night. But they can still be found where they sleep, which is often up in trees high off the ground. We spotted this one doing just that just above eye level on a late night hike. These long, slender snakes are great climbers, and this is a reasonably safe spot for such an animal to evade predators and get off the hot ground.
A Gila Monster I followed to a nest of cottontails. It took a while, but it ate all three of them that were in there. Amazingly, they all fit, and the lizard ambled off to rest under an overhanging root in the drainage. It was a good example of how the venom of Gila Monsters is not necessary for predation, as the venom played no apparent role in the capture or consumption of its prey.
A Southwestern Speckled Rattlesnake in ambush on a humid night a couple of years back. Like many other desert reptiles, the monsoon and period after are the most active times of year. Humid air and cooler, stable temperatures make for safer activity, and a lot has to be done in a relatively short amount of time.
Southwestern Speckled Rattlesnake (Crotalus pyrrhus)