Brook trout (Salvelinus fontinalis) in Tennessee : an ecological genetic study using allozyme electrophoresis and Random Amplified Polymorphic DNA

Allozyme electrophoresis was used to examine 56 populations of brook trout (Salvelinus fontinalis) from East Tennessee outside the Great Smoky Mountains National Park. Six diagnostic loci were used to classify twenty-six populations as native southern (unstocked), six as northern (hatchery-derived), and twenty-four as hybrid (stocked) or putative hybrid. Data from a total of 15 loci, all known to be polymorphic, were used to describe the genetic structure of these populations. Native southern populations had higher genetic similarity to each other than to northern populations, however, there is substantial genetic divergence among native southern populations, even among populations within a watershed. Genetic divergence among native southern populations will make preservation of this genetic resource difficult because management strategies will need to focus on individual streams. Random Amplified Polymorphic DNA (RAPDs) was used to examine a subset of seven of the brook trout populations. It was possible to use RAPDs to discriminate between native southern and northern populations in this preliminary study. Genetic distance estimates using RAPD data were not significantly different from genetic distance estimates using allozyme data. Average number of polymorphic b