A young Sonoran Sidewinder (Crotalus cerastes cercobombus) with a nice, clean pattern near Phoenix last year. These small rattlesnakes are very common in the right habitat, but rarely seen by hikers because of the nature of that same habitat.
Southwestern Speckled Rattlesnakes (Crotalus pyrrhus) are commonly seen by hikers in the Phoenix area at popular parks, even those entirely within the city. They have a relatively extreme level of camouflage for a rattlesnake, and many people are surprised to learn just how many rattlesnakes they walk by even at the most heavily-hiked parks in the city. This is one of several hundred that inhabit one of these parks, found on a hillside below a trail.
A Southwestern Speckled Rattlesnake making its way up a nearly vertical wall, taking advantage of numerous leverage opportunities. Rattlesnakes can climb, but not with the same skill as some non-venomous snakes, like gophersnakes or kingsnakes. Even from a moderate height, a fall can injure or even kill the animal, so caution is needed.
I met this Gila Monster out and about on a spring day in 2023. At the time, there were a lot of quail eggs and baby cottontails to find out there, which gets these animals active and observable.
These animals are the only venomous lizard in the United States, and one of five species of the Heloderma genus found across Central America.
A Southwestern Speckled Rattlesnake I found in Cave Creek, Arizona. These snakes are common in the mountains of the area, where they often appear in this pink color.
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.
