Long-distance dispersal (LDD) includes rare events in which propagules arrive, but do not necessarily establish, at a site far removed from their origin. Although important in a variety of ecological contexts, the context-specific nature of LDD makes it difficult to define. We critically review the main methods employed in studies of dispersal, in order to facilitate the evaluation of their pertinence to specific aspects of LDD research. Using a novel classification framework, we identify six main methodological groups: biogeographical; Eulerian and Lagrangian movement/redistributional; short-term and long-term genetic analyses; and modeling. We briefly discuss the strengths and weaknesses of the most promising methods available for estimation of LDD, illustrating them with examples from current studies. The rarity of LDD events makes it difficult to collect, analyze, and interpret the necessary data. A simple and comprehensive definition of LDD remains elusive. Yet, considerable advances have been made in some methodological areas, such as miniaturization of tracking devices. Combinations of methods are increasingly used to approach LDD from multiple angles and provide improved insight. However, the increased homogenization of the world's biota because of human activities is increasingly reducing our ability to study natural LDD events.
Key words. Long-distance dispersal; Dispersal curve; Dispersal distance; Spatial Scale; Realized dispersal; Dispersal Data; Biogeography; Tracking individuals; Population Redistribution; Genetic analysis; Models; Human-Mediated Dispersal