The aim of this study was to construct a microsatellite library for the pest moth Heliothis armigera and to use this library to investigate temporal shifts in population structure. Specifically, the aim of the study was to determine whether 1998-1999 seasonal infestations of H armigera in south western Queensland were the result of migration from an external source or were derived from previous populations. A secondary aim was to investigate the relationship between larval survivorship and source population