RABATSKY, A. M.; University of Louisiana at Lafayette: Caudal luring and defensive tail display in the dusky pigmy rattlesnake, Sistrurus miliarius barbouri, with comments on ontogenies and evolution

Snakes utilize their tails for many uses including foraging and defense. In this study, I investigated caudal luring and defensive tail display in the dusky pigmy rattlesnake, Sistrurus miliarius barbouri. Ontogenies within these behaviors were also considered. Caudal luring occurred exclusively in the presence of prey and by juveniles. When caudal luring, rattle segmentation had no effect on the number of prey that moved within striking distance of the snake. Defensive tail display occurred in equal frequency to rattling but more often in adults. Sex differences occurred in caudal luring but not in defensive tail display. Because tail movements functioned both to attract prey and distract predators and foraging on insectivorous prey is paedomorphic in this species, selection for traits that enhance the conspicuousness of the tail are suspected to be strong. Appropriate use of the term caudal luring and conditions under which this behavior should be suspected are also discussed.