Social security? Evidence of stress reduction through social buffering in rattlesnakes

Martin, Chelsea

Fox, Gerad

Putman, Breanna

Hayes, William K.

Department of Earth & Biological Sciences

Loma Linda University

Loma Linda, California USA

Social buffering is the reduction of stress an organism experiences when in the presence of a companion. It has been well-documented in highly social animals such as birds and mammals; however, it has not been reported in reptiles. Furthermore, most previous work has been conducted on laboratory-bred animals, consequently we lack knowledge on whether and how social buffering occurs in nature. Rattlesnakes are cryptically social, exhibiting the ability to recognize kin and forming subtle social networks in at least some populations. Pregnant females often aggregate at rookeries, and rattlesnakes in cooler climates frequently overwinter in communal hibernacula. We tested the presence of social buffering against acute stress in 25 wild-caught adult Southern Pacific Rattlesnakes (Crotalus helleri) by measuring the increase of heart rate during a standardized disturbance when alone, in the presence of a rope (inanimate object control), or in the presence of a same-sex companion. Preliminary results suggest that snakes with a companion had a reduced increase in heart rate and reduced behavioral defensiveness after disturbance compared to solitary snakes. Further research is underway to examine social buffering against chronic stress. These novel studies can fill the gap in our understanding of social buffering, including its evolution, adaptive roles, and practical applications.