Data from: Population genetic structure of the western cherry fruit fly Rhagoletis indifferens (Diptera: Tephritidae) in British Columbia, Canada

1. Population connectivity and movement are key ecological parameters
influencing the impact of pests, and are important considerations in
control strategies. For many insects, these parameters are difficult to
assess directly, although they may be assessed indirectly using population
genetic data. 2. We used microsatellite markers to examine population
genetic structure of the western cherry fruit fly, the main pest of cherry
crops in western North America, in British Columbia, Canada, and make
inferences about connectivity and potential for movement among
populations. 3. Comparing populations from four geographical regions
(separated by up to approximately 400 km), we found significant genetic
differentiation both among and within regions. Using populations as the
units of analysis, we observed significant isolation by distance (IBD) at
larger spatial scales but not below approximately 20 km. By contrast,
using individual flies as the units of analysis, we found significant IBD
at scales as small as < 100 m. We saw no evidence of genetic
differentiation among populations sampled from different species/varieties
of plants. 4. Our results suggest that the movement of individual flies is
limited, although high levels of gene flow are maintained at scales of up
to 20 km, possibly through combined effects of stepping-stone gene flow
and large population sizes.