Altitudinal migration of insects

Abstract

AbstractA number of insects have been suggested to perform seasonal migration between low‐ and high‐altitude areas. In these insects, support for the occurrence of migration mainly came from observations that focal insects disappeared from a certain range of altitudes but appeared at different altitudes with short time lags. In some insects, further support was obtained by mark–recapture studies, analyses of the seasonal change of age structure or reproductive conditions in individuals from different altitudes and studies on dormancy or temperature tolerance. Other means that can be used to assess the occurrence of altitudinal migration are briefly mentioned. Two types of migration, the dormancy‐associated and dormancy‐independent types, are discriminated. In the former type, insects usually breed in spring, migrate to high‐altitude areas in late spring or early summer, usually for aestivation, and return to low‐altitude areas in autumn. In this type, the same individuals perform upward and downward migration. In the latter type, insects also perform upward migration in late spring or early summer and downward migration in autumn, but they breed both in low‐ and high‐altitude areas. The adaptive and evolutionary aspects of altitudinal migration are briefly mentioned.