Male mate-locating behavior and yearly population cycles in the snout butterfly, Libytheana bachmanh (Libytheidae)

This paper describes mating behavior and seasonal changes in population size in the snout butterfly, Libytheana bachmanii. At a central Arizona study site, we found a dramatic peak in the abundance of snout butterflies in late May and early June, with a smaller peak in the fall. Both peaks lasted several weeks and were separated by periods when few or no adult butterflies were found. Males are classic patrollers and search for females in and around the larval foodplant, desert hackberry (Celtis pallida). Courtship is like that of many other butterflies, with no distinctive displays by the male or female. We compare these results to those for the desert hackberry butterfly, Asterocampa leilia, which uses the same larval foodplant but has very different mate-locating tactics and, as some hypotheses predict, relatively stable and medium density populations from season to season.