Black Bass Diversity: Multidisciplinary Science for Conservation

Implications of Microsatellite DNA Variation upon Management of Virginia Smallmouth Bass Populations

Eric M. Hallerman, Nathan Johnson, and Dan Dutton

doi: https://doi.org/10.47886/9781934874400.ch44

Abstract.—Virginia is at the edge of the range of Micropterus dolomieu dolomieu, and it is uncertain whether they are native to particular watersheds. Patterns of population genetic variation could inform knowledge of natural history and provide the scientific basis for management of the species. Three-hundred fifteen individuals representing 13 populations were screened at 10 microsatellite DNA loci. Numbers of alleles per locus ranged from 2 to 10. Collections from native Tennessee River drainage populations were more variable (4.5 alleles/locus) than the New River collection (4.3) and those for introduced populations (3.8), although numbers of alleles for the respective groups overlapped. More genetic variation was found within (82.7%) than between (17.3%) populations. Geographic structuring of genetic variation was weak, but tended to show divergence of Caddo Lake, Arkansas (the M. d. velox outgroup) from the Clinch and Powell, Holston, and New River and Atlantic slope collections. Analysis of our results in the context of existing knowledge suggests that the New and James River populations may be admixtures of native and introduced gene pools. Our findings suggest that the Clinch–Powell and Holston River populations should be regarded as two management units, New River populations as another, and introduced populations as yet another. Because native stocks are likely to be locally adapted, we recommend assessment of potential adaptive variation and no stocking from outside of each management unit.