Western Diamondback Rattlesnake Ingress

A Western Diamondback Rattlesnake sitting outside of its den in late November. Days later, it disappeared into the rock pile to hibernate.

In Maricopa County, ingress to their selected overwintering sites typically concludes by about the second week of November, unlike Spring emergence, which is a longer process of basking and social behavior that puts them on the surface every day for weeks or more, getting to the den itself is typically less active.

Females and young snakes tend to disappear immediately, likely to avoid burning off the moisture and energy stored throughout the year. Males, especially the larger and older individuals, may continue to bask and conduct social dominance behavior for awhile, before again disappearing to stable, hidden conditions.

For homeowners, this means that the locations where they may be found change dramatically in nature. Unlike pass-through rattlesnake encounters from the Fall, a snake found from November through February is a long-term resident. This also means that these situations are also very fixable. The stable environmental conditions offered by something like an unused wood pile, access under an old shed, or other easy thermostable situation, are very useful. Once the snake is relocated, the homeowner should receive the information about the situation needed to solve the real issue.

Western Diamondback Rattlesnake from Hidalgo County New Mexico

A Western Diamondback Rattlesnake found in the bootheel of New Mexico many years ago. The diamondbacks in this area have some interesting traits that make them a bit different than those found in the Phoenix and Tucson areas. They’re often pink or rose colored, with a diminished pattern that can fade to a minimal look … and they can change color between darker and lighter tones within hours.

Courtship and Mating of Western Diamondback Rattlesnakes

This pair of Western Diamondback Rattlesnakes were found at a den in central Arizona near the edge of the species range in the area. With at least fifty observable individuals, this is a large den for these snakes in the state, which is also shares with Blacktailed Rattlesnakes and Arizona Black Rattlesnakes. With multiple large males roving around, I was watching hoping for combat, but it didn’t happen this day. This photo was taken right after the snakes eventually moved from courtship to mating, with tails elevated. They remained in this location for at least the rest of the day.