There are stark coloration differences within single populations of Thamnophis sirtalis such as the Isle Royale population. While these red color patterns cause the snakes to stand out, it is unsure if it is for some defensive purpose such as aposematic coloring. To see if this or other genetic factors, sex, and relatedness with litters, could influence behavior anti-predator and feeding tests were performed on 38 captive-born neonate T. sirtalis. The feeding experiment recorded the latency of feeding from placement of the piece of night crawler to food capture. The anti-predator experiment recorded reactions to a probe touching each snake 20 times with three seconds in between. The feeding results indicated that there is a connection between that behavior and litter but not coloration or sex. This held true for the anti-predator behaviors of directional reversals and freezing but none of the groups showed any connection to total active anti-predator behaviors. There were also no correlations between the anti-predator and feeding behaviors. Litter seems to be the strongest indicator of behavior.
Porter, Jennifer F. and Burghardt, Gordon M., "Litter, Color Variation, and Sex Effects on Feeding and Anti-Predator Behavior in Individual Thamnophis sirtalis" (2012). Ecology and Evolutionary Biology Publications and Other Works.