Noninvasive and Cost-Effective Trapping Method for Monitoring Sensitive Mammal Populations

Noninvasive sampling methods provide a means to monitor endangered, threatened, or sensitive species or populations while increasing the efficacy of personnel effort and time. We developed a monitoring protocol that utilizes single-capture hair snares and analysis of morphological features of hair for evaluating populations. During 2015, we used the West Virginia northern flying squirrel (Glaucomys sabrinus fuscus) in the Monongahela National Forest, West Virginia, USA, to test the feasibility of using this protocol to sample a sensitive mammal species found at low densities in challenging terrain and inclement weather conditions. Our hair snare was successful in collecting hair from 316 squirrels of 3 species with 99.4% single captures and only 1 permanent capture. Using morphological analysis, we differentiated among northern flying squirrels, southern flying squirrels (G. volans), and red squirrels (Tamiasciurus hudsonicus) using 8 morphological measurements and an orthogonal discriminant function analysis to successfully refine and confirm identification of the hair. We advocate the use of this relatively noninvasive and inexpensive protocol for studying other sensitive wildlife species.