New (and Fascinating) Research on Rattlesnakes!

In my picture book, Don’t Make Me Rattle, I discuss some of the social behavior of rattlesnakes. People often think of them as solitary, aggressive predators roaming their territories. In my book, I described how, in their winter, they share their hibernacula with other rattlers and other hibernating/brumating animals. (Mammals hibernate, reptiles brumate.)

I recently read new research on the social interactions of rattlesnakes, specifically Crotalus atrox (western diamondback rattlesnake). This work by Sasha J. Tetzlaff, Jeferson Vizentin-Bugoni, Jinelle H. Sperry, Mark A. Davis, Rulon W. Clark, Roger A. Repp, Gordon W. Schuett was published in Ecology and Evolution: Fission–fusion dynamics in the social networks of a North American pit viper.

Gatherings of rattlers change in size and composition over time and in different locations. The behaviors of particular interest included communal winter dens, mating, and offspring production. 

Fascinating Findings

The researchers found that adult snakes gathered in ‘moderately’ sized groups in winter dens. Both inside and outside of the dens, mating occurred with fewer and different partners. However, the mating pairs often didn’t stay together. They observed no long-term relationships among diamondbacks. This is unsurprising since females mate with multiple partners, can store sperm long-term, and give birth (live) to offspring with varied paternity—a plus for genetic diversity.

When the rattlers head out in the spring to return to their home ranges, they are not interested in socializing with others of their kind despite having plenty of opportunities, even though many have overlapping ranges.

Female diamondbacks, who had been part of a den group before, often want to spend the winter alone. Early observations suggest these solitary females stay away from the males to avoid getting pregnant. They may have had a rough year, and their bodies are in less-than-ideal shape. They feel they aren’t strong enough to bear young. Remember, rattlesnakes give birth to live young. They don’t just produce a few eggs, lay them, and take off. No, rattlesnake mothers must provide for their babies during their entire development. They also care for them once they are born!

Therefore, it’s not simply genetically determined behavior in western diamondbacks. They can adjust their behavior to ensure their survival and commitment to the well-being of future offspring.

We have so much more to learn about rattlesnakes, in general, and my local western diamondback rattlesnakes, specifically. Hopefully, with knowledge, our fear of them will transform into respect. If you’d like to learn more about rattlesnake behavior, take a look at my educational workbooks!