Chapter 5 Threats
associated with transportation development also brings an increased risk of the introduction of exotic species. Fragmentation disrupts dispersal of many species, especially those that migrate between wet lowlands and dry uplands and can negatively affect population dynamics and reproductive success. Fragmentation influences evolution by changing, among other things, the costs and benefits of dispersal (Stockwell et al. 2003) . A decrease in population dispersal and population size can lead to a reduction in the effective population size followed by increased genetic drift; reduced genetic variation and increased inbreeding; and a decrease in the time to extinction (Marsack and Swanson 2009; Anderson et al . 2004) . Inbreeding contributes to genetic mutations that decrease disease resistance and the ability of a population to adapt (Lacy 1993) . While most birds can rapidly find and colonize early successional habitat patches, some bird species (grassland birds in particular) are area sensitive and will not use small patches of habitat surrounded by forest or developed areas. Northern Bobwhite Quail may require large (more than 5,000 acres) areas of contiguous habitat for long-term population viability (Guthery et al. 2000) . Fragmentation of forests into smaller contiguous blocks is a concern for forest interior birds (like the Wood Thrush, Cooper’s Hawk, and Worm-eating Warbler), which may occur in lower densities or suffer lower productivity or survival in small habitat patches. Animals with large home ranges or dispersal needs may become isolated or absent in small tracts. Fragmentation by roads and development can be particularly problematic for reptiles (particularly Timber Rattlesnakes and Box Turtles), amphibians, and small mammals that suffer high mortality on roads when traveling between forest patches. Upland changes will influence landscapes containing wetlands through changes in downstream outputs and hydrological and biogeochemical processes. Drainage and agricultural activities can degrade nearby wetlands and cause loss of vegetation diversity and ecosystem services (De Steven and Gramling 2013) . 5.9.2 SGCN Priority Species The Taxa Team evaluation considered the level of threat natural system modifications represents to SGCN priority species. Lists of the SGCN and other priority species this threat is expected to have a very high or high impact on can be found in Appendix 5, Table 5.9-1 Species at Risk of Impacts From Natural System Modifications.
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2025 NC Wildlife Action Plan
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