Chapter 4 Habitats
Lack of sufficient vegetation or inadequate width of forested buffer contributes to rising water temperatures, especially where water depths are shallow enough that the entire water column is subject to solar heating. In addition to stabilizing streambanks, riparian vegetation serves as a food/nutrient input to the stream community and helps regulate stream temperature by providing shade. Water Quality. Erosion and the resultant sedimentation are the largest sources of nonpoint source pollution in most aquatic systems. Development activities and agriculture can be the most significant sources of erosion and sediment. Timber harvests and poorly constructed and maintained timber roads are additional sources of erosion if proper controls are not used and maintained. Increased stormwater runoff will amplify the loading of nutrients, sediment, and contaminants into streams, rivers, and reservoirs. The increased loads could affect water quality and habitat for aquatic species, as well as drinking water for municipalities. Stormwater controls and retrofits will become increasingly important (Band and Salvesen 2009) . Algal blooms are possible in these systems and can exacerbate DO problems, particularly when flows are low. Increased water temperature, resuspension of bottom sediment during storms, and increased nutrient content of freshwater and coastal waters can increase pathogen replication, persistence, survival, and transmission (DeWan et al. 2010; Karl et al. 2009; Band and Salvesen 2009; US EPA 2010) . Confined animal operations are common in the Coastal Plain ecoregion and may have significant impacts on water resources. Livestock access to streams contributes heavily to bank erosion, sedimentation, and nutrient input. Animal waste lagoon discharges are a potential source of contamination if not properly managed and maintained. Invasive Species . The introduction of any invasive species is cause for concern and the prevalence of warmer water temperatures may increase the presence of exotic species that were previously thought to be non-threatening because the winters were too cold for survival. The Asian Clam is found in aquatic systems throughout the state; however, its effects on native mussels are largely unknown. Red Swamp Crawfish are prevalent in the Coastal Plain, and although effects on native crayfish are not fully understood, it is likely that competition for resources such as food and space is a potential impact. Flathead Catfish are a concern because of direct predation on native species. Climate Impacts . Increased air temperatures may lead to increased water temperatures and potentially lower DO levels. Stream swamp communities experience periodic temperature increases and DO decreases that may be exacerbated by changing climate conditions. Higher air and water temperatures can also lead to increased evaporation, which results in less flowing water available for aquatic species to use. Hot spells can have the same effect as overall increased air temperatures but on a much more acute scale.
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2025 NC Wildlife Action Plan
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