4.4 Terrestrial Communities
4.4.15.3 Problems Affecting Habitats Tese communities are well adapted to overwash and this may or may not be harmful to them. It may reverse the artifcial exclusion of overwash that has altered some examples, such as those on parts of Bodie and Hatteras islands and the Currituck Banks. Overwash is important for transporting sand to the back of barrier islands, allowing them to migrate landward with rising sea level. Increased erosion of foredunes and possible disappearance of whole barrier islands will substantially reduce acreage. Tis group will likely shrink drastically in the near future. Te most extensive examples occur on narrow barrier islands which are most likely to disappear or be substantially altered by erosion. Examples should survive where barrier islands are able to migrate. Examples should survive on larger, more stable, higher islands, and may migrate to higher elevations or expand there at the expense of maritime upland forest and maritime wetland forest. Much of the narrower part of the Outer Banks could disappear entirely (Riggs 2010) . With the loss of area will come increased fragmentation, which is already a problem in smaller examples that are isolated by developed areas. Barrier islands can be expected to migrate landward, if allowed to, and could survive if sea level does not rise too rapidly. Te wider, more stable, and generally higher parts of barrier islands are likely to remain. Grassland communities will also shift and change as the result of increased storm activity and its associated erosion, increased salt spray, overwash, and saltwater intrusion. Increased coastal erosion may breach the foredunes, allowing over- wash, which can ofset the efects of artifcial barriers (e.g., sand fencing and plantings) installed to alter the structure of dune grass communities. Increased natural disturbance and milder temperatures can be expected to change com- position. Species native to comparable communities farther south may be able to migrate in. Because the harsh physical environment already limits species present, and because the expected changes on surviving islands are mostly increases in processes already active, the degree of compositional change is expected to be limited in most of these communi- ties. Structural changes may be more signifcant. However the wet grasslands in particular may be more drastically afected. New exotic species may appear or become invasive in the warmer climate, though none are specifcally known. Mild winters may allow new exotic species to invade, or may allow more natural compositional change that will be locally sub- stantial but may be negligible over larger areas. 4.4.15.4 Climate Change Compared to Other Threats Comparing climate change to other ecosystem threats can help defne short- and long-term conservation actions and recommendations. While the climate is expected to be warmer, and rainfall change estimates vary widely, the most important efects on these systems will
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2015 NC Wildlife Action Plan
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