4.4 Terrestrial Communities
4.4.1.3 Problems Affecting Habitats Given the variability in cave types, mine types, and a host of diferent substrates, orienta- tions, positions on the landscape, etc., the condition of caves and mines in North Carolina is quite variable. Caves and mines occur across all land ownership types. Several of the most signifcant sites have received attention in the past to protect resources (wildlife or geological in most cases). Bat-friendly gates have been installed in some locations to pro- hibit or regulate human entry and subsequent impacts upon cave resources. However, modifcations at cave entrances and gate design and placement will potentially impede air exchange, ultimately exerting infuence on the ambient and substrate temperatures inside caves, which in turn will infuence the body temperature and metabolic rates of hibernat- ing bats (McNab 1974; Humphrey 1978; Martin et al. 2006) . We have no accurate assessment of the wildlife habitat potential of abandoned mines in North Carolina, and certainly have little idea as to their individual suitability for use by cave-dwelling animals or plants. Some portion of abandoned subsurface mines are likely to function similarly to caves in providing the range of microhabitat conditions which cave-obligate species need, especially larger mine excavations that can provide the volume and air fow needed by cave-dwelling species (particularly bats of various species). Smaller mines may support minor levels of use, or use by small numbers of individuals. Seasonal variations in surface climate, entrance characteristics (Tuttle and Stevenson 1978) and physical structure of the cave itself (Twente 1955; Raesly and Gates 1987) are thought to have the greatest impact on the climate of cave interiors (Martin et al. 2006) . Changes in precipitation may contribute to variation in moisture and temperature but may not be drastic. Drought conditions cause moisture gradients in caves and mines to change, especially those with groundwater seepage contributing to the humidity level. Warmer temperatures will change the suitability of this habitat for species adapted to historic microclimate conditions. Human activities alter the microclimate, biogeochemistry, and balance of organic matter in caves, which also impacts microbial communities (Saiz-Jimenez 2012) . Several research arti- cles have reported on declines of cave-obligate bats caused by human disturbance at caves (Martin et al. 2006) . In many states, and throughout the world, many caves have been devel- oped into tourist attractions, often with lighting, tours, gates, etc. All of these activities have resulted in degraded habitat conditions for cave-dwelling animals as well as disrupted normal behavior patterns, efectively eliminating habitat for many cave animals. Te Southern Blue Ridge Ecoregional Conservation Plan noted recreation, including developed tourist caves and recreational caving/exploration, to be the greatest threat to cave and cave species conservation (TNC and SAFC 2000) .
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2015 NC Wildlife Action Plan
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