Applying genetic methods to identify northern and southern flying squirrels and determine conservation needs

The two species of flying squirrels found in North America are the northern (Glaucomys sabrinus) and the southern (G. volans) flying squirrel. Both species have wide range distributions across North America, yet differences in their preferred habitat result in few areas of sympatry. Climate change however, has shifted the southern flying squirrel's range limit further north, thus allowing the two species to encounter each other more frequently. Glaucomys volans is the more competitive of the two, and also carries a nematode parasite (Strongyloides robustus) proven to be deleterious towards its sister species. The northern incursion of the southern flying squirrel may therefore dislodge its sister species from its original distribution. With G. sabrinus considered endangered in different parts of North America, and G. volans listed as "concerned" in its northernmost limit, the two species require close monitoring. Morphological identification is often challenging for incomplete and juvenile specimens, therefore we developed a molecular identification protocol using mitochondrial and nuclear markers in tandem to help distinguish each species. These protocols were tested on Glaucomys individuals located elsewhere in Canada and the USA to ensure the validity of the designed primers. Moreover, employing our methods may detect F1 hybrids. To assess the current genetic portrait of G. sabrinus populations in Quebec before the potential invasion of its sister species, a preliminary population genetics study using seven microsatellite loci was also realized. The various conservation and management implications are discussed.