Colony interactions in Reticulitermes grassei population assessed by molecular genetic methods

Abstract.

The cryptic habits of subterranean termites impair studies of colony delimitation and the organization of foraging. Whereas feeding sites can be identified and the movements of foragers between them can be assessed using traditional mark-release techniques, the assignment of the termites found at feeding sites to their parent colonies remains problematical. Thus the extent and overlap of individual colony foraging territories are unknown. We used microsatellite markers to delineate colonies of R. grassei and compared the results with data from a mark-release-recapture study (Nobre et al., 2007) carried out in the same population and over the same period of time. The majority of colonies exhibited only a single-feeding site, but presented, even at a local scale, a high degree of variability in colony structure and no evidence of inbreeding. F-statistics for some colonies were consistent with pleometrosis. The population as a whole contained individual colonies that were separately identified as Mendelian, mixed family or pleometrotic families. Furthermore, microsatellite data suggest that what was represented by the MRR technique as a single foraging group could be drawn from more than one colony. Colony delineation is discussed as a tool for understanding overall population structure and termite feeding strategies.