Summary: Eastern North American migratory monarch butterflies exhibit migratory behavioral states in fall and spring characterized by sun-dependent oriented flight.However, it is unclear how monarchs transition between these behavioral states at their overwintering site.Using a modified Mouritsen-Frost flight simulator, we confirm individual directionality and compass-based orientation (leading to group orientation) in fall migrants, and also uncover sustained flight propensity and COMBAT PRO GEL KEY LIME direction-based flight reinforcement as distinctly migratory behavioral traits.
By testing monarchs at their Mexican overwintering sites, we 4 Way Hotplate Control Switch show that overwintering monarchs show reduced propensity for sustained flight and lose individual directionality, leading to the loss of group-level orientation.Overwintering fliers orient axially in a time-of-day dependent manner, which may indicate local versus long-distance directional heading.These results support a model of migratory flight behavior in which modular, state-dependent switches for flight propensity and orientation control are highly dynamic and are controlled in season- and location-dependent manners.