Mating behavior among many moth species is mediated by female-released pheromones that attract males over distance. Males of the western spruce budworm, Choristoneura occidentalis Freeman, are attracted by pheromone which has been identified and synthesized (Cory et al. 1982; Silk et al. 1982). In response to pheromone, males will fly upwind and thus approach a bait on a fir limb, then land and persistently search near the bait, often locating it (Sower and Shorb 1985). Male budworm moths moving upwind toward a pheromone source are seen to use a wandering, left-and-right and up-and-down flight pattern. This is the classic anemotactic response of male moths to female-released pheromone as described by Shorey (1976), David et al. (1983), and references therein.