4.3 Wetland Natural Communities
4.3.1.3 Problems Affecting Habitats Invasive Species. Invasive species are already a problem in some areas and may increase with drought and warmer temperatures. Some bogs are subject to invasion by exotic plants such as Japanese Stiltgrass, Multifora Rose, and Asian Dayfower. Many of these communi- ties contain pines, hemlocks, or spruces, which are susceptible to insect pests. Drought and warm temperatures may allow generalists and upland species to invade. Many of the rare species associated with mountain bogs and fens are herbs and are vulner- able to competition from woody species and more aggressive habitat generalists. If changes in hydrology make these sites drier, this problem is likely to be exacerbated. Climate Impacts. Besides stream fooding, overland runof from adjacent uplands during severe storms would be a problem in many bogs. Te nutrient input and potential scouring of severe foods would be detrimental to bog communities. Droughts would have signif- cant efects on competitive relationships among species and on the community as a whole. Many bogs may reduce in size if margins dry out due to drought. Some estimates indicate that fewer than 500 acres of mountain bogs in North Carolina remain (USFWS 2002) . Fragmentation . Te most common types of fragmentation occur when streams are impounded to form lakes, highways are built across inhabited wetlands, and wetland habitat units are drained for agricultural use or development. Roads that bisect Bog Turtle wetlands are the single most detrimental threat to turtle populations. Highway mortality is high in areas where turtles must cross roads to get from one wetland to another (Somers et al. 2000) . Successional Conversion . Bog communities can undergo ecological succession, from open canopy fens and bogs to closed canopy swamps (where hydrologic conditions do not change), leading to the loss of habitat suitable for Bog Turtles and other species dependent on these types of wetlands (Klemens 1993; Herman and Tryon 1997; Rosenbaum et al. 2007) . 4.3.1.4 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 climate change is not the most severe threat, a combination of synergistic efects with other existing conditions could stress these systems to the point where several species are unable to persist. Climate change efects such as droughts and severe fooding may be particularly problem- atic in these communities. Climate change, however, is not likely to be as detrimental com- pared to impacts caused by a number of immediate threats that can cause more drastic destruction than climate change is likely to. Te largest scale problem afecting mountain
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2015 NC Wildlife Action Plan
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