Caudal luring is a behavior used by many ambush-foraging snakes that increases their encounter rate with prey. In this study, we used the dusky pigmy rattlesnake, Sistrurus miliarius barbouri, in a series of trials involving prey and measured the frequency and duration of caudal luring. This behavior varied ontogenetically, with adults never performing caudal luring. Juveniles that lured for longer durations were more successful in attracting prey. Males and females caudal lured in equal frequency but females took longer time periods to achieve a similar level of foraging success. Because the tails are sexually dimorphic in this species, we suggest that the longer tail of the male may be a more effective luring device. This is the first quantification of a sex difference in caudal luring, and the results suggest important differences in foraging ecology among males and females.