Using Distance-sampling to Estimate Density of White-tailed Deer in Forested, Mountainous Landscapes in Virginia

• Published in: Northeastern naturalist 2017-12, Vol.24 (4), p.505-519
• Main Authors: Montague, David M, Montague, Roxzanna D, Fies, Michael L, Kelly, Marcella J
• Format: Article
• Language: English
• Subjects: Abiotic factors; Athletes; Deer; Forests; Group size; Habitats; Hunting; Landscape; Mountain forests; Mountain regions; Mountainous areas; Odocoileus virginianus; Polls & surveys; Population density; Private lands; Public lands; Sampling; Wildlife management; Wind speed
• ISSN: 1092-6194; 1938-5307
• DOI: 10.1656/045.024.0409

Although Odocoileus virginianus (White-tailed Deer, hereafter, Deer) are abundant on private lands throughout much of the western Virginia mountain region, populations are comparatively low on publicly owned lands in this area. Concerns voiced by sportsmen regarding declining numbers of Deer on public lands in western Virginia prompted research to estimate the population density in selected areas within this region. From January 2012 through April 2013, we used ground-based transect sampling with forward-looking infrared (FLIR) techniques in a distance-sampling framework to estimate seasonal Deer density in mountainous western Virginia. We included habitat variables and abiotic factors thought to influence detection and ranked models using AICc model selection in the program DISTANCE. We observed 430 groups of Deer (mean group size = 2.9) during 5 sampling sessions conducted along 562.5 km traveled in Bath County, versus 102 groups (mean group size = 2.6) along 643.6 km in Rockingham County. Wind speed negatively affected detection, and minimum temperature positively influenced detection. Detection rates were higher in open areas and forest edges, and higher closer to a full moon. Overall, we found Deer densities to be lower in the mountainous areas we sampled compared to the few studies using similar sampling techniques in other nearby areas of the state. Additionally, we found that while density did not vary seasonally, Deer densities were higher in Bath County (4.75–16.06 Deer/km2) than in Rockingham County (0.17–3.55 Deer/km2), likely due to the presence of more edge and open habitat in Bath County. We suggest that distance estimation is a viable technique to survey Deer, but caution that our sample sizes were small for some surveys and suggest that future research should seek to account for low detection rates on national forest lands by increasing effort.