4.3 Wetland Natural Communities
Water Quality. Water quality impacts from pesticide use (related to mosquito control), sec- ondary impacts from development, and water fow impacts caused by ditching and canals have greatly afected this habitat. Failing septic systems, sewage treatment and marina cleanout efuents, stormwater runof, industrial organic waste discharge, and agricultural fertilizers or animal wastes contribute excessive nutrients that can result in eutrophication and algal blooms. Mats of algae block sunlight from penetrating the water and will impact sea grasses. Low DO levels can result from algal die-of and decay and excessive algae growth can result in brown or red tides and harmful blooms, such as Pfesteria piscicida, that have been associated with fsh kills (EPA 2012b) . Climate Change . Climate change impacts, primarily sea level rise, will lead to shifts in plant composition and more open water habitats. An increase in the number of storm events and storm severity will result in more fooding and erosion of vegetation. Te pres- ence of drainage ditches will facilitate saltwater intrusion into more inland natural com- munities and rapid decomposition of peat soils by sulfate-reducing bacteria (Hackney and Yelverton 1990) . Other problems will include subsidence and increased inundation of fresh- water communities and release of previously sequestered carbon as carbon dioxide and methane (Hackney and Yelverton 1990) . 4.3.2.4 Climate Change Compared to Other Threats Climate change, particularly rising sea level and the potential erosion of barrier islands, is the greatest threat to estuarine wetland communities. Table 4.16 summarizes the compari- son of climate change with other existing threats. 4.3.2.5 Impacts to Wildlife Appendix G provides a list of SGCN and other priority species for which there are knowl- edge gaps and management concerns. Appendix H identifes SGCN that depend on or are associated with estuarine wetlands. Many bird species associated with these community types have experienced signifcant declines according to inventory and survey data. Several priority bird species, such as the Seaside Sparrow, Northern Harrier, American Bittern, and Black Rail, are ground nesters in estuarine marsh habitats. If marsh habitat does not migrate inland at comparable rates to habitat losses, these birds may be displaced permanently due to fragmentation and compe- tition pressures. Waterbird species that are colonial nesters are vulnerable to loss of habitat because they have relatively few nesting locations. Beach-nesting birds, sea turtles, and terrapins are more likely to have their nests washed over as sea level rises.
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2015 NC Wildlife Action Plan
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