Speckled Rattlesnake in Ambush

A Southwestern Speckled Rattlesnake found in ambush at sunup on a hot day in Arizona. Nearby, a cave with several more has been used as an aestivation site to avoid death in the summer months.

This photograph was taken in 2014. In recent years, the site has been abandoned, most likely due to increased human activity, based on evidence and observation of similar sites in the region.

Southwestern Speckled Rattlesnake in Phoenix

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.

Sidewinder, The Horned Rattlesnake

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

Gila Monster Out and About

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)