Date of Award
Master of Science (MS)
Wildlife and Fisheries Biology
Patrick R. Jodice, Committee Chair
Patrick D. Gerard
Susan C. Loeb
Early successional habitat (ESH) is important for many wildlife species. Over the past century, land use changes have caused ESH to decline in hardwood forests of the eastern United States. The decline of ESH and ESH dependent wildlife has caused concern among land managers and scientists. Bats, which utilize ESH for foraging, are also a conservation concern, however little information is available on how ESH restoration affects bats. My objective was to determine how opening size, presence of edge, prey abundance, vegetation structure, and environmental factors affect bat activity in forest openings. In June-August 2014 and May-August 2015, I placed Anabat SD2 bat detectors at the interior and edge of small (0.2-1.6 ha), medium (2.1-5.6 ha), and large (6.2-18.5 ha) forest openings in the Nantahala National Forest Cheoah Ranger District, Graham County, North Carolina. Call files recorded were filtered using AnalookW and identified to species using Kaleidoscope Pro. Townes-style Malaise insect traps were paired with each bat detector and insects captured were counted and identified to order. iButton temperature loggers were also paired with each bat detector and used to determine mean nightly temperature. Vegetation surveys were conducted to quantify vegetation structure. Difference in insect abundance, bat activity, and bat species richness were tested using mixed effects general linear models. Opening size and presence of edge did not affect total insect abundance, however there was a positive effect of live and dead tree basal area and mean nightly temperature. Overall bat activity was significantly higher at opening edges compared to opening interiors, was positively related to mean nightly temperature, and was negatively related to vegetation structure. Activity of open-adapted species was also negatively related to vegetation structure. These results suggest that opening size and prey abundance do not affect bat activity in the southern Appalachian Mountains, however vegetation structure and environmental factors are important. Open-adapted bats may select foraging patches with less vegetation structure because they can forage more efficiently in these environments, whereas clutter-adapted bats can forage efficiently in both cluttered and open environments. When creating ESH, land managers should maintain an open vegetation structure to benefit open-adapted bat species, focus on creating openings at lower elevations, and configure openings to maximize edge relative to opening area.
Brooks, Jonathan Daniel, "Effect of Forest Opening Characteristics, Prey Abundance, and Environmental Factors on Bat Activity in the Southern Appalachians" (2016). All Theses. 2485.