While aggregations of many squamate reptiles may be transient and resource-based, rattlesnakes are a likely candidate to exhibit complex sociality.  Using a combination of personal observations and remote timelapse photography, we have found that juvenile and adult Arizona black rattlesnakes (Crotalus cerberus) aggregate together to overwinter and some females gestate and care for their young in small groups at or near these social hibernacula (overwintering sites).  One potential hypothesis to explain sociality in rattlesnakes is habitat limitation; rattlesnakes may aggregate because there are few appropriate sites for these activities (i.e., overwintering, gestation).

At The Nature Conservancy’s Muleshoe Ranch, we are exploring the habitat limitation hypothesis for rattlesnake sociality.  We are using radio telemetry to locate hibernacula of Arizona black rattlesnakes and sympatric (co-occurring) western diamond-backed (Crotalus atrox) and black-tailed rattlesnakes (Crotalus molossus).  If social aggregations of rattlesnakes can be explained by habitat limitation alone, then sympatric rattlesnakes should exhibit the same denning behavior in the same habitat.  We are currently tracking one black-tailed, two diamond-backed, and four Arizona black rattlesnakes to investigate their social behavior at Muleshoe Ranch.

Another important aspect of this study is education.  Hatred and fear of snakes has led to widespread persecution and obstruction to conservation efforts.  Our blogs (also see Social Snakes) and local presentations bring snakes to people.  At Muleshoe Ranch, we will bring people into the snakes’ world.  Ranch guests will get a chance to visit social hibernacula and experience a day in the life of a rattlesnake.  Eventually we will expand this program to bring in other members of the public including urban school groups.